njp NJOPFM New Journal of Physics NJP New J. Phys. 1367-2630 IOP Publishing njpaa3714 10.1088/1367-2630/18/9/093016 aa3714 NJP-105169.R1 Paper Search for scalar leptoquarks in pp collisions at s  = 13 TeV with the ATLAS experiment Search for scalar leptoquarks in pp collisions at s  = 13 TeV with the ATLAS experiment The ATLAS Collaboration Aaboud M 136d Aad G 87 Abbott B 114 Abdallah J 65 Abdinov O 12 Abeloos B 118 Aben R 108 AbouZeid O S 138 Abraham N L 150 Abramowicz H 154 Abreu H 153 Abreu R 117 Abulaiti Y 147a 147b Acharya B S 164a 164b 179 Adamczyk L 40a Adams D L 27 Adelman J 109 Adomeit S 101 Adye T 132 Affolder A A 76 Agatonovic-Jovin T 14 Agricola J 56 Aguilar-Saavedra J A 127a 127f Ahlen S P 24 Ahmadov F 67 180 Aielli G 134a 134b Akerstedt H 147a 147b Åkesson T P A 83 Akimov A V 97 Alberghi G L 22a 22b Albert J 169 Albrand S 57 Alconada Verzini M J 73 Aleksa M 32 Aleksandrov I N 67 Alexa C 28b Alexander G 154 Alexopoulos T 10 Alhroob M 114 Aliev M 75a 75b Alimonti G 93a Alison J 33 Alkire S P 37 Allbrooke B M M 150 Allen B W 117 Allport P P 19 Aloisio A 105a 105b Alonso A 38 Alonso F 73 Alpigiani C 139 Alstaty M 87 Alvarez Gonzalez B 32 Álvarez Piqueras D 167 Alviggi M G 105a 105b Amadio B T 16 Amako K 68 Amaral Coutinho Y 26a Amelung C 25 Amidei D 91 Amor Dos Santos S P 127a 127c Amorim A 127a 127b Amoroso S 32 Amundsen G 25 Anastopoulos C 140 Ancu L S 51 Andari N 109 Andeen T 11 Anders C F 60b Anders G 32 Anders J K 76 Anderson K J 33 Andreazza A 93a 93b Andrei V 60a Angelidakis S 9 Angelozzi I 108 Anger P 46 Angerami A 37 Anghinolfi F 32 Anisenkov A V 110 181 Anjos N 13 Annovi A 125a 125b Antonelli M 49 Antonov A 99 Anulli F 133a Aoki M 68 Aperio Bella L 19 Arabidze G 92 Arai Y 68 Araque J P 127a Arce A T H 47 Arduh F A 73 Arguin J-F 96 Argyropoulos S 65 Arik M 20a Armbruster A J 144 Armitage L J 78 Arnaez O 32 Arnold H 50 Arratia M 30 Arslan O 23 Artamonov A 98 Artoni G 121 Artz S 85 Asai S 156 Asbah N 44 Ashkenazi A 154 Åsman B 147a 147b Asquith L 150 Assamagan K 27 Astalos R 145a Atkinson M 166 Atlay N B 142 Augsten K 129 Avolio G 32 Axen B 16 Ayoub M K 118 Azuelos G 96 182 Baak M A 32 Baas A E 60a Baca M J 19 Bachacou H 137 Bachas K 75a 75b Backes M 32 Backhaus M 32 Bagiacchi P 133a 133b Bagnaia P 133a 133b Bai Y 35a Baines J T 132 Baker O K 176 Baldin E M 110 181 Balek P 130 Balestri T 149 Balli F 137 Balunas W K 123 Banas E 41 Banerjee Sw 173 183 Bannoura A A E 175 Barak L 32 Barberio E L 90 Barberis D 52a 52b Barbero M 87 Barillari T 102 Barklow T 144 Barlow N 30 Barnes S L 86 Barnett B M 132 Barnett R M 16 Barnovska Z 5 Baroncelli A 135a Barone G 25 Barr A J 121 Barranco Navarro L 167 Barreiro F 84 Barreiro Guimarães da Costa J 35a Bartoldus R 144 Barton A E 74 Bartos P 145a Basalaev A 124 Bassalat A 118 Bates R L 55 Batista S J 159 Batley J R 30 Battaglia M 138 Bauce M 133a 133b Bauer F 137 Bawa H S 144 184 Beacham J B 112 Beattie M D 74 Beau T 82 Beauchemin P H 162 Bechtle P 23 Beck H P 18 185 Becker K 121 Becker M 85 Beckingham M 170 Becot C 111 Beddall A J 20e Beddall A 20b Bednyakov V A 67 Bedognetti M 108 Bee C P 149 Beemster L J 108 Beermann T A 32 Begel M 27 Behr J K 44 Belanger-Champagne C 89 Bell A S 80 Bella G 154 Bellagamba L 22a Bellerive A 31 Bellomo M 88 Belotskiy K 99 Beltramello O 32 Belyaev N L 99 Benary O 154 Benchekroun D 136a Bender M 101 Bendtz K 147a 147b Benekos N 10 Benhammou Y 154 Benhar Noccioli E 176 Benitez J 65 Benjamin D P 47 Bensinger J R 25 Bentvelsen S 108 Beresford L 121 Beretta M 49 Berge D 108 Bergeaas Kuutmann E 165 Berger N 5 Beringer J 16 Berlendis S 57 Bernard N R 88 Bernius C 111 Bernlochner F U 23 Berry T 79 Berta P 130 Bertella C 85 Bertoli G 147a 147b Bertolucci F 125a 125b Bertram I A 74 Bertsche C 44 Bertsche D 114 Besjes G J 38 Bessidskaia Bylund O 147a 147b Bessner M 44 Besson N 137 Betancourt C 50 Bethke S 102 Bevan A J 78 Bhimji W 16 Bianchi R M 126 Bianchini L 25 Bianco M 32 Biebel O 101 Biedermann D 17 Bielski R 86 Biesuz N V 125a 125b Biglietti M 135a Bilbao De Mendizabal J 51 Bilokon H 49 Bindi M 56 Binet S 118 Bingul A 20b Bini C 133a 133b Biondi S 22a 22b Bjergaard D M 47 Black C W 151 Black J E 144 Black K M 24 Blackburn D 139 Blair R E 6 Blanchard J-B 137 Blanco J E 79 Blazek T 145a Bloch I 44 Blocker C 25 Blum W 85 224 Blumenschein U 56 Blunier S 34a Bobbink G J 108 Bobrovnikov V S 110 181 Bocchetta S S 83 Bocci A 47 Bock C 101 Boehler M 50 Boerner D 175 Bogaerts J A 32 Bogavac D 14 Bogdanchikov A G 110 Bohm C 147a Boisvert V 79 Bokan P 14 Bold T 40a Boldyrev A S 164a 164c Bomben M 82 Bona M 78 Boonekamp M 137 Borisov A 131 Borissov G 74 Bortfeldt J 101 Bortoletto D 121 Bortolotto V 62a 62b 62c Bos K 108 Boscherini D 22a Bosman M 13 Bossio Sola J D 29 Boudreau J 126 Bouffard J 2 Bouhova-Thacker E V 74 Boumediene D 36 Bourdarios C 118 Boutle S K 55 Boveia A 32 Boyd J 32 Boyko I R 67 Bracinik J 19 Brandt A 8 Brandt G 56 Brandt O 60a Bratzler U 157 Brau B 88 Brau J E 117 Braun H M 175 224 Breaden Madden W D 55 Brendlinger K 123 Brennan A J 90 Brenner L 108 Brenner R 165 Bressler S 172 Bristow T M 48 Britton D 55 Britzger D 44 Brochu F M 30 Brock I 23 Brock R 92 Brooijmans G 37 Brooks T 79 Brooks W K 34b Brosamer J 16 Brost E 117 Broughton J H 19 Bruckman de Renstrom P A 41 Bruncko D 145b Bruneliere R 50 Bruni A 22a Bruni G 22a Bruni L S 108 Brunt B H 30 Bruschi M 22a Bruscino N 23 Bryant P 33 Bryngemark L 83 Buanes T 15 Buat Q 143 Buchholz P 142 Buckley A G 55 Budagov I A 67 Buehrer F 50 Bugge M K 120 Bulekov O 99 Bullock D 8 Burckhart H 32 Burdin S 76 Burgard C D 50 Burghgrave B 109 Burka K 41 Burke S 132 Burmeister I 45 Busato E 36 Büscher D 50 Büscher V 85 Bussey P 55 Butler J M 24 Buttar C M 55 Butterworth J M 80 Butti P 108 Buttinger W 27 Buzatu A 55 Buzykaev A R 110 181 Cabrera Urbán S 167 Caforio D 129 Cairo V M 39a 39b Cakir O 4a Calace N 51 Calafiura P 16 Calandri A 87 Calderini G 82 Calfayan P 101 Caloba L P 26a Calvet D 36 Calvet S 36 Calvet T P 87 Camacho Toro R 33 Camarda S 32 Camarri P 134a 134b Cameron D 120 Caminal Armadans R 166 Camincher C 57 Campana S 32 Campanelli M 80 Camplani A 93a 93b Campoverde A 142 Canale V 105a 105b Canepa A 160a Cano Bret M 35e 35f Cantero J 115 Cantrill R 127a Cao T 42 Capeans Garrido M D M 32 Caprini I 28b Caprini M 28b Capua M 39a 39b Caputo R 85 Carbone R M 37 Cardarelli R 134a Cardillo F 50 Carli I 130 Carli T 32 Carlino G 105a Carminati L 93a 93b Caron S 107 Carquin E 34b Carrillo-Montoya G D 32 Carter J R 30 Carvalho J 127a 127c Casadei D 19 Casado M P 13 186 Casolino M 13 Casper D W 163 Castaneda-Miranda E 146a Castelijn R 108 Castelli A 108 Castillo Gimenez V 167 Castro N F 127a 187 Catinaccio A 32 Catmore J R 120 Cattai A 32 Caudron J 85 Cavaliere V 166 Cavallaro E 13 Cavalli D 93a Cavalli-Sforza M 13 Cavasinni V 125a 125b Ceradini F 135a 135b Cerda Alberich L 167 Cerio B C 47 Cerqueira A S 26b Cerri A 150 Cerrito L 78 Cerutti F 16 Cerv M 32 Cervelli A 18 Cetin S A 20d Chafaq A 136a Chakraborty D 109 Chan S K 59 Chan Y L 62a Chang P 166 Chapman J D 30 Charlton D G 19 Chatterjee A 51 Chau C C 159 Chavez Barajas C A 150 Che S 112 Cheatham S 74 Chegwidden A 92 Chekanov S 6 Chekulaev S V 160a Chelkov G A 67 188 Chelstowska M A 91 Chen C 66 Chen H 27 Chen K 149 Chen S 35c Chen S 156 Chen X 35g Chen Y 69 Cheng H C 91 Cheng H J 35a Cheng Y 33 Cheplakov A 67 Cheremushkina E 131 Cherkaoui El Moursli R 136e Chernyatin V 27 224 Cheu E 7 Chevalier L 137 Chiarella V 49 Chiarelli G 125a 125b Chiodini G 75a Chisholm A S 19 Chitan A 28b Chizhov M V 67 Choi K 63 Chomont A R 36 Chouridou S 9 Chow B K B 101 Christodoulou V 80 Chromek-Burckhart D 32 Chudoba J 128 Chuinard A J 89 Chwastowski J J 41 Chytka L 116 Ciapetti G 133a 133b Ciftci A K 4a Cinca D 55 Cindro V 77 Cioara I A 23 Ciocio A 16 Cirotto F 105a 105b Citron Z H 172 Citterio M 93a Ciubancan M 28b Clark A 51 Clark B L 59 Clark M R 37 Clark P J 48 Clarke R N 16 Clement C 147a 147b Coadou Y 87 Cobal M 164a 164c Coccaro A 51 Cochran J 66 Coffey L 25 Colasurdo L 107 Cole B 37 Colijn A P 108 Collot J 57 Colombo T 32 Compostella G 102 Conde Muiño P 127a 127b Coniavitis E 50 Connell S H 146b Connelly I A 79 Consorti V 50 Constantinescu S 28b Conti G 32 Conventi F 105a 189 Cooke M 16 Cooper B D 80 Cooper-Sarkar A M 121 Cormier K J R 159 Cornelissen T 175 Corradi M 133a 133b Corriveau F 89 190 Corso-Radu A 163 Cortes-Gonzalez A 13 Cortiana G 102 Costa G 93a Costa M J 167 Costanzo D 140 Cottin G 30 Cowan G 79 Cox B E 86 Cranmer K 111 Crawley S J 55 Cree G 31 Crépé-Renaudin S 57 Crescioli F 82 Cribbs W A 147a 147b Crispin Ortuzar M 121 Cristinziani M 23 Croft V 107 Crosetti G 39a 39b Cuhadar Donszelmann T 140 Cummings J 176 Curatolo M 49 Cúth J 85 Cuthbert C 151 Czirr H 142 Czodrowski P 3 D’amen G 22a 22b D’Auria S 55 D’Onofrio M 76 Da Cunha Sargedas De Sousa M J 127a 127b Da Via C 86 Dabrowski W 40a Dado T 145a Dai T 91 Dale O 15 Dallaire F 96 Dallapiccola C 88 Dam M 38 Dandoy J R 33 Dang N P 50 Daniells A C 19 Dann N S 86 Danninger M 168 Dano Hoffmann M 137 Dao V 50 Darbo G 52a Darmora S 8 Dassoulas J 3 Dattagupta A 63 Davey W 23 David C 169 Davidek T 130 Davies M 154 Davison P 80 Dawe E 90 Dawson I 140 Daya-Ishmukhametova R K 88 De K 8 de Asmundis R 105a De Benedetti A 114 De Castro S 22a 22b De Cecco S 82 De Groot N 107 de Jong P 108 De la Torre H 84 De Lorenzi F 66 De Maria A 56 De Pedis D 133a De Salvo A 133a De Sanctis U 150 De Santo A 150 De Vivie De Regie J B 118 Dearnaley W J 74 Debbe R 27 Debenedetti C 138 Dedovich D V 67 Dehghanian N 3 Deigaard I 108 Del Gaudio M 39a 39b Del Peso J 84 Del Prete T 125a 125b Delgove D 118 Deliot F 137 Delitzsch C M 51 Deliyergiyev M 77 Dell’Acqua A 32 Dell’Asta L 24 Dell’Orso M 125a 125b Della Pietra M 105a 189 della Volpe D 51 Delmastro M 5 Delsart P A 57 Deluca C 108 DeMarco D A 159 Demers S 176 Demichev M 67 Demilly A 82 Denisov S P 131 Denysiuk D 137 Derendarz D 41 Derkaoui J E 136d Derue F 82 Dervan P 76 Desch K 23 Deterre C 44 Dette K 45 Deviveiros P O 32 Dewhurst A 132 Dhaliwal S 25 Di Ciaccio A 134a 134b Di Ciaccio L 5 Di Clemente W K 123 Di Donato C 133a 133b Di Girolamo A 32 Di Girolamo B 32 Di Micco B 135a 135b Di Nardo R 32 Di Simone A 50 Di Sipio R 159 Di Valentino D 31 Diaconu C 87 Diamond M 159 Dias F A 48 Diaz M A 34a Diehl E B 91 Dietrich J 17 Diglio S 87 Dimitrievska A 14 Dingfelder J 23 Dita P 28b Dita S 28b Dittus F 32 Djama F 87 Djobava T 53b Djuvsland J I 60a do Vale M A B 26c Dobos D 32 Dobre M 28b Doglioni C 83 Dohmae T 156 Dolejsi J 130 Dolezal Z 130 Dolgoshein B A 99 224 Donadelli M 26d Donati S 125a 125b Dondero P 122a 122b Donini J 36 Dopke J 132 Doria A 105a Dova M T 73 Doyle A T 55 Drechsler E 56 Dris M 10 Du Y 35d Duarte-Campderros J 154 Duchovni E 172 Duckeck G 101 Ducu O A 96 191 Duda D 108 Dudarev A 32 Duffield E M 16 Duflot L 118 Duguid L 79 Dührssen M 32 Dumancic M 172 Dunford M 60a Duran Yildiz H 4a Düren M 54 Durglishvili A 53b Duschinger D 46 Dutta B 44 Dyndal M 44 Eckardt C 44 Ecker K M 102 Edgar R C 91 Edwards N C 48 Eifert T 32 Eigen G 15 Einsweiler K 16 Ellajosyula V 87 Ellert M 165 Elles S 5 Ellinghaus F 175 Elliot A A 169 Ellis N 32 Elmsheuser J 27 Elsing M 32 Emeliyanov D 132 Enari Y 156 Endner O C 85 Endo M 119 Ennis J S 170 Erdmann J 45 Ereditato A 18 Ernis G 175 Ernst J 2 Ernst M 27 Errede S 166 Ertel E 85 Escalier M 118 Esch H 45 Escobar C 126 Esposito B 49 Etienvre A I 137 Etzion E 154 Evans H 63 Ezhilov A 124 Fabbri F 22a 22b Fabbri L 22a 22b Facini G 33 Fakhrutdinov R M 131 Falciano S 133a Falla R J 80 Faltova J 130 Fang Y 35a Fanti M 93a 93b Farbin A 8 Farilla A 135a Farina C 126 Farooque T 13 Farrell S 16 Farrington S M 170 Farthouat P 32 Fassi F 136e Fassnacht P 32 Fassouliotis D 9 Faucci Giannelli M 79 Favareto A 52a 52b Fawcett W J 121 Fayard L 118 Fedin O L 124 192 Fedorko W 168 Feigl S 120 Feligioni L 87 Feng C 35d Feng E J 32 Feng H 91 Fenyuk A B 131 Feremenga L 8 Fernandez Martinez P 167 Fernandez Perez S 13 Ferrando J 55 Ferrari A 165 Ferrari P 108 Ferrari R 122a Ferreira de Lima D E 60b Ferrer A 167 Ferrere D 51 Ferretti C 91 Ferretto Parodi A 52a 52b Fiedler F 85 Filipčič A 77 Filipuzzi M 44 Filthaut F 107 Fincke-Keeler M 169 Finelli K D 151 Fiolhais M C N 127a 127c Fiorini L 167 Firan A 42 Fischer A 2 Fischer C 13 Fischer J 175 Fisher W C 92 Flaschel N 44 Fleck I 142 Fleischmann P 91 Fletcher G T 140 Fletcher R R M 123 Flick T 175 Floderus A 83 Flores Castillo L R 62a Flowerdew M J 102 Forcolin G T 86 Formica A 137 Forti A 86 Foster A G 19 Fournier D 118 Fox H 74 Fracchia S 13 Francavilla P 82 Franchini M 22a 22b Francis D 32 Franconi L 120 Franklin M 59 Frate M 163 Fraternali M 122a 122b Freeborn D 80 Fressard-Batraneanu S M 32 Friedrich F 46 Froidevaux D 32 Frost J A 121 Fukunaga C 157 Fullana Torregrosa E 85 Fusayasu T 103 Fuster J 167 Gabaldon C 57 Gabizon O 175 Gabrielli A 22a 22b Gabrielli A 16 Gach G P 40a Gadatsch S 32 Gadomski S 51 Gagliardi G 52a 52b Gagnon L G 96 Gagnon P 63 Galea C 107 Galhardo B 127a 127c Gallas E J 121 Gallop B J 132 Gallus P 129 Galster G 38 Gan K K 112 Gao J 35b 87 Gao Y 48 Gao Y S 144 184 Garay Walls F M 48 García C 167 García Navarro J E 167 Garcia-Sciveres M 16 Gardner R W 33 Garelli N 144 Garonne V 120 Gascon Bravo A 44 Gatti C 49 Gaudiello A 52a 52b Gaudio G 122a Gaur B 142 Gauthier L 96 Gavrilenko I L 97 Gay C 168 Gaycken G 23 Gazis E N 10 Gecse Z 168 Gee C N P 132 Geich-Gimbel Ch 23 Geisen M 85 Geisler M P 60a Gemme C 52a Genest M H 57 Geng C 35b 193 Gentile S 133a 133b George S 79 Gerbaudo D 13 Gershon A 154 Ghasemi S 142 Ghazlane H 136b Ghneimat M 23 Giacobbe B 22a Giagu S 133a 133b Giannetti P 125a 125b Gibbard B 27 Gibson S M 79 Gignac M 168 Gilchriese M 16 Gillam T P S 30 Gillberg D 31 Gilles G 175 Gingrich D M 3 182 Giokaris N 9 Giordani M P 164a 164c Giorgi F M 22a Giorgi F M 17 Giraud P F 137 Giromini P 59 Giugni D 93a Giuli F 121 Giuliani C 102 Giulini M 60b Gjelsten B K 120 Gkaitatzis S 155 Gkialas I 155 Gkougkousis E L 118 Gladilin L K 100 Glasman C 84 Glatzer J 32 Glaysher P C F 48 Glazov A 44 Goblirsch-Kolb M 102 Godlewski J 41 Goldfarb S 91 Golling T 51 Golubkov D 131 Gomes A 127a 127b 127d Gonçalo R 127a Goncalves Pinto Firmino Da Costa J 137 Gonella G 50 Gonella L 19 Gongadze A 67 González de la Hoz S 167 Gonzalez Parra G 13 Gonzalez-Sevilla S 51 Goossens L 32 Gorbounov P A 98 Gordon H A 27 Gorelov I 106 Gorini B 32 Gorini E 75a 75b Gorišek A 77 Gornicki E 41 Goshaw A T 47 Gössling C 45 Gostkin M I 67 Goudet C R 118 Goujdami D 136c Goussiou A G 139 Govender N 146b 194 Gozani E 153 Graber L 56 Grabowska-Bold I 40a Gradin P O J 57 Grafström P 22a 22b Gramling J 51 Gramstad E 120 Grancagnolo S 17 Gratchev V 124 Gravila P M 28e Gray H M 32 Graziani E 135a Greenwood Z D 81 195 Grefe C 23 Gregersen K 80 Gregor I M 44 Grenier P 144 Grevtsov K 5 Griffiths J 8 Grillo A A 138 Grimm K 74 Grinstein S 13 196 Gris Ph 36 Grivaz J-F 118 Groh S 85 Grohs J P 46 Gross E 172 Grosse-Knetter J 56 Grossi G C 81 Grout Z J 150 Guan L 91 Guan W 173 Guenther J 129 Guescini F 51 Guest D 163 Gueta O 154 Guido E 52a 52b Guillemin T 5 Guindon S 2 Gul U 55 Gumpert C 32 Guo J 35e 35f Guo Y 35b 193 Gupta S 121 Gustavino G 133a 133b Gutierrez P 114 Gutierrez Ortiz N G 80 Gutschow C 46 Guyot C 137 Gwenlan C 121 Gwilliam C B 76 Haas A 111 Haber C 16 Hadavand H K 8 Haddad N 136e Hadef A 87 Haefner P 23 Hageböck S 23 Hajduk Z 41 Hakobyan H 177 224 Haleem M 44 Haley J 115 Halladjian G 92 Hallewell G D 87 Hamacher K 175 Hamal P 116 Hamano K 169 Hamilton A 146a Hamity G N 140 Hamnett P G 44 Han L 35b Hanagaki K 68 197 Hanawa K 156 Hance M 138 Haney B 123 Hanke P 60a Hanna R 137 Hansen J B 38 Hansen J D 38 Hansen M C 23 Hansen P H 38 Hara K 161 Hard A S 173 Harenberg T 175 Hariri F 118 Harkusha S 94 Harrington R D 48 Harrison P F 170 Hartjes F 108 Hartmann N M 101 Hasegawa M 69 Hasegawa Y 141 Hasib A 114 Hassani S 137 Haug S 18 Hauser R 92 Hauswald L 46 Havranek M 128 Hawkes C M 19 Hawkings R J 32 Hayden D 92 Hays C P 121 Hays J M 78 Hayward H S 76 Haywood S J 132 Head S J 19 Heck T 85 Hedberg V 83 Heelan L 8 Heim S 123 Heim T 16 Heinemann B 16 Heinrich J J 101 Heinrich L 111 Heinz C 54 Hejbal J 128 Helary L 24 Hellman S 147a 147b Helsens C 32 Henderson J 121 Henderson R C W 74 Heng Y 173 Henkelmann S 168 Henriques Correia A M 32 Henrot-Versille S 118 Herbert G H 17 Hernández Jiménez Y 167 Herten G 50 Hertenberger R 101 Hervas L 32 Hesketh G G 80 Hessey N P 108 Hetherly J W 42 Hickling R 78 Higón-Rodriguez E 167 Hill E 169 Hill J C 30 Hiller K H 44 Hillier S J 19 Hinchliffe I 16 Hines E 123 Hinman R R 16 Hirose M 158 Hirschbuehl D 175 Hobbs J 149 Hod N 160a Hodgkinson M C 140 Hodgson P 140 Hoecker A 32 Hoeferkamp M R 106 Hoenig F 101 Hohn D 23 Holmes T R 16 Homann M 45 Hong T M 126 Hooberman B H 166 Hopkins W H 117 Horii Y 104 Horton A J 143 Hostachy J-Y 57 Hou S 152 Hoummada A 136a Howarth J 44 Hrabovsky M 116 Hristova I 17 Hrivnac J 118 Hryn’ova T 5 Hrynevich A 95 Hsu C 146c Hsu P J 152 198 Hsu S-C 139 Hu D 37 Hu Q 35b Huang Y 44 Hubacek Z 129 Hubaut F 87 Huegging F 23 Huffman T B 121 Hughes E W 37 Hughes G 74 Huhtinen M 32 Hülsing T A 85 Huo P 149 Huseynov N 67 180 Huston J 92 Huth J 59 Iacobucci G 51 Iakovidis G 27 Ibragimov I 142 Iconomidou-Fayard L 118 Ideal E 176 Idrissi Z 136e Iengo P 32 Igonkina O 108 199 Iizawa T 171 Ikegami Y 68 Ikeno M 68 Ilchenko Y 11 200 Iliadis D 155 Ilic N 144 Ince T 102 Introzzi G 122a 122b Ioannou P 9 224 Iodice M 135a Iordanidou K 37 Ippolito V 59 Ishino M 70 Ishitsuka M 158 Ishmukhametov R 112 Issever C 121 Istin S 20a Ito F 161 Iturbe Ponce J M 86 Iuppa R 134a 134b Iwanski W 41 Iwasaki H 68 Izen J M 43 Izzo V 105a Jabbar S 3 Jackson B 123 Jackson M 76 Jackson P 1 Jain V 2 Jakobi K B 85 Jakobs K 50 Jakobsen S 32 Jakoubek T 128 Jamin D O 115 Jana D K 81 Jansen E 80 Jansky R 64 Janssen J 23 Janus M 56 Jarlskog G 83 Javadov N 67 180 Javůrek T 50 Jeanneau F 137 Jeanty L 16 Jejelava J 53a 201 Jeng G-Y 151 Jennens D 90 Jenni P 50 202 Jentzsch J 45 Jeske C 170 Jézéquel S 5 Ji H 173 Jia J 149 Jiang H 66 Jiang Y 35b Jiggins S 80 Jimenez Pena J 167 Jin S 35a Jinaru A 28b Jinnouchi O 158 Johansson P 140 Johns K A 7 Johnson W J 139 Jon-And K 147a 147b Jones G 170 Jones R W L 74 Jones S 7 Jones T J 76 Jongmanns J 60a Jorge P M 127a 127b Jovicevic J 160a Ju X 173 Juste Rozas A 13 196 Köhler M K 172 Kaczmarska A 41 Kado M 118 Kagan H 112 Kagan M 144 Kahn S J 87 Kajomovitz E 47 Kalderon C W 121 Kaluza A 85 Kama S 42 Kamenshchikov A 131 Kanaya N 156 Kaneti S 30 Kanjir L 77 Kantserov V A 99 Kanzaki J 68 Kaplan B 111 Kaplan L S 173 Kapliy A 33 Kar D 146c Karakostas K 10 Karamaoun A 3 Karastathis N 10 Kareem M J 56 Karentzos E 10 Karnevskiy M 85 Karpov S N 67 Karpova Z M 67 Karthik K 111 Kartvelishvili V 74 Karyukhin A N 131 Kasahara K 161 Kashif L 173 Kass R D 112 Kastanas A 15 Kataoka Y 156 Kato C 156 Katre A 51 Katzy J 44 Kawagoe K 72 Kawamoto T 156 Kawamura G 56 Kazama S 156 Kazanin V F 110 181 Keeler R 169 Kehoe R 42 Keller J S 44 Kempster J J 79 Kentaro K 104 Keoshkerian H 159 Kepka O 128 Kerševan B P 77 Kersten S 175 Keyes R A 89 Khalil-zada F 12 Khanov A 115 Kharlamov A G 110 181 Khoo T J 51 Khovanskiy V 98 Khramov E 67 Khubua J 53b 203 Kido S 69 Kim H Y 8 Kim S H 161 Kim Y K 33 Kimura N 155 Kind O M 17 King B T 76 King M 167 King S B 168 Kirk J 132 Kiryunin A E 102 Kishimoto T 69 Kisielewska D 40a Kiss F 50 Kiuchi K 161 Kivernyk O 137 Kladiva E 145b Klein M H 37 Klein M 76 Klein U 76 Kleinknecht K 85 Klimek P 147a 147b Klimentov A 27 Klingenberg R 45 Klinger J A 140 Klioutchnikova T 32 Kluge E-E 60a Kluit P 108 Kluth S 102 Knapik J 41 Kneringer E 64 Knoops E B F G 87 Knue A 55 Kobayashi A 156 Kobayashi D 158 Kobayashi T 156 Kobel M 46 Kocian M 144 Kodys P 130 Koffas T 31 Koffeman E 108 Koi T 144 Kolanoski H 17 Kolb M 60b Koletsou I 5 Komar A A 97 224 Komori Y 156 Kondo T 68 Kondrashova N 44 Köneke K 50 König A C 107 Kono T 68 204 Konoplich R 111 205 Konstantinidis N 80 Kopeliansky R 63 Koperny S 40a Köpke L 85 Kopp A K 50 Korcyl K 41 Kordas K 155 Korn A 80 Korol A A 110 181 Korolkov I 13 Korolkova E V 140 Kortner O 102 Kortner S 102 Kosek T 130 Kostyukhin V V 23 Kotwal A 47 Kourkoumeli-Charalampidi A 155 Kourkoumelis C 9 Kouskoura V 27 Kowalewska A B 41 Kowalewski R 169 Kowalski T Z 40a Kozakai C 156 Kozanecki W 137 Kozhin A S 131 Kramarenko V A 100 Kramberger G 77 Krasnopevtsev D 99 Krasny M W 82 Krasznahorkay A 32 Kraus J K 23 Kravchenko A 27 Kretz M 60c Kretzschmar J 76 Kreutzfeldt K 54 Krieger P 159 Krizka K 33 Kroeninger K 45 Kroha H 102 Kroll J 123 Kroseberg J 23 Krstic J 14 Kruchonak U 67 Krüger H 23 Krumnack N 66 Kruse A 173 Kruse M C 47 Kruskal M 24 Kubota T 90 Kucuk H 80 Kuday S 4b Kuechler J T 175 Kuehn S 50 Kugel A 60c Kuger F 174 Kuhl A 138 Kuhl T 44 Kukhtin V 67 Kukla R 137 Kulchitsky Y 94 Kuleshov S 34b Kuna M 133a 133b Kunigo T 70 Kupco A 128 Kurashige H 69 Kurochkin Y A 94 Kus V 128 Kuwertz E S 169 Kuze M 158 Kvita J 116 Kwan T 169 Kyriazopoulos D 140 La Rosa A 102 La Rosa Navarro J L 26d La Rotonda L 39a 39b Lacasta C 167 Lacava F 133a 133b Lacey J 31 Lacker H 17 Lacour D 82 Lacuesta V R 167 Ladygin E 67 Lafaye R 5 Laforge B 82 Lagouri T 176 Lai S 56 Lammers S 63 Lampl W 7 Lançon E 137 Landgraf U 50 Landon M P J 78 Lang V S 60a Lange J C 13 Lankford A J 163 Lanni F 27 Lantzsch K 23 Lanza A 122a Laplace S 82 Lapoire C 32 Laporte J F 137 Lari T 93a Lasagni Manghi F 22a 22b Lassnig M 32 Laurelli P 49 Lavrijsen W 16 Law A T 138 Laycock P 76 Lazovich T 59 Lazzaroni M 93a 93b Le B 90 Le Dortz O 82 Le Guirriec E 87 Le Quilleuc E P 137 LeBlanc M 169 LeCompte T 6 Ledroit-Guillon F 57 Lee C A 27 Lee S C 152 Lee L 1 Lefebvre G 82 Lefebvre M 169 Legger F 101 Leggett C 16 Lehan A 76 Lehmann Miotto G 32 Lei X 7 Leight W A 31 Leisos A 155 206 Leister A G 176 Leite M A L 26d Leitner R 130 Lellouch D 172 Lemmer B 56 Leney K J C 80 Lenz T 23 Lenzi B 32 Leone R 7 Leone S 125a 125b Leonidopoulos C 48 Leontsinis S 10 Lerner G 150 Leroy C 96 Lesage A A J 137 Lester C G 30 Levchenko M 124 Levêque J 5 Levin D 91 Levinson L J 172 Levy M 19 Lewis D 78 Leyko A M 23 Leyton M 43 Li B 35b 193 Li H 149 Li H L 33 Li L 47 Li L 35e 35f Li Q 35a Li S 47 Li X 86 Li Y 142 Liang Z 35a Liberti B 134a Liblong A 159 Lichard P 32 Lie K 166 Liebal J 23 Liebig W 15 Limosani A 151 Lin S C 152 207 Lin T H 85 Lindquist B E 149 Lionti A E 51 Lipeles E 123 Lipniacka A 15 Lisovyi M 60b Liss T M 166 Lister A 168 Litke A M 138 Liu B 152 208 Liu D 152 Liu H 91 Liu H 27 Liu J 87 Liu J B 35b Liu K 87 Liu L 166 Liu M 47 Liu M 35b Liu Y L 35b Liu Y 35b Livan M 122a 122b Lleres A 57 Llorente Merino J 35a Lloyd S L 78 Lo Sterzo F 152 Lobodzinska E 44 Loch P 7 Lockman W S 138 Loebinger F K 86 Loevschall-Jensen A E 38 Loew K M 25 Loginov A 176 Lohse T 17 Lohwasser K 44 Lokajicek M 128 Long B A 24 Long J D 166 Long R E 74 Longo L 75a 75b Looper K A 112 Lopes L 127a Lopez Mateos D 59 Lopez Paredes B 140 Lopez Paz I 13 Lopez Solis A 82 Lorenz J 101 Lorenzo Martinez N 63 Losada M 21 Lösel P J 101 Lou X 35a Lounis A 118 Love J 6 Love P A 74 Lu H 62a Lu N 91 Lubatti H J 139 Luci C 133a 133b Lucotte A 57 Luedtke C 50 Luehring F 63 Lukas W 64 Luminari L 133a Lundberg O 147a 147b Lund-Jensen B 148 Luzi P M 82 Lynn D 27 Lysak R 128 Lytken E 83 Lyubushkin V 67 Ma H 27 Ma L L 35d Ma Y 35d Maccarrone G 49 Macchiolo A 102 Macdonald C M 140 Maček B 77 Machado Miguens J 123 127b Madaffari D 87 Madar R 36 Maddocks H J 165 Mader W F 46 Madsen A 44 Maeda J 69 Maeland S 15 Maeno T 27 Maevskiy A 100 Magradze E 56 Mahlstedt J 108 Maiani C 118 Maidantchik C 26a Maier A A 102 Maier T 101 Maio A 127a 127b 127d Majewski S 117 Makida Y 68 Makovec N 118 Malaescu B 82 Malecki Pa 41 Maleev V P 124 Malek F 57 Mallik U 65 Malon D 6 Malone C 144 Maltezos S 10 Malyukov S 32 Mamuzic J 167 Mancini G 49 Mandelli B 32 Mandelli L 93a Mandić I 77 Maneira J 127a 127b Manhaes de Andrade Filho L 26b Manjarres Ramos J 160b Mann A 101 Manousos A 32 Mansoulie B 137 Mansour J D 35a Mantifel R 89 Mantoani M 56 Manzoni S 93a 93b Mapelli L 32 Marceca G 29 March L 51 Marchiori G 82 Marcisovsky M 128 Marjanovic M 14 Marley D E 91 Marroquim F 26a Marsden S P 86 Marshall Z 16 Marti-Garcia S 167 Martin B 92 Martin T A 170 Martin V J 48 Martin dit Latour B 15 Martinez M 13 196 Martin-Haugh S 132 Martoiu V S 28b Martyniuk A C 80 Marx M 139 Marzin A 32 Masetti L 85 Mashimo T 156 Mashinistov R 97 Masik J 86 Maslennikov A L 110 181 Massa I 22a 22b Massa L 22a 22b Mastrandrea P 5 Mastroberardino A 39a 39b Masubuchi T 156 Mättig P 175 Mattmann J 85 Maurer J 28b Maxfield S J 76 Maximov D A 110 181 Mazini R 152 Mazza S M 93a 93b Mc Fadden N C 106 Mc Goldrick G 159 Mc Kee S P 91 McCarn A 91 McCarthy R L 149 McCarthy T G 102 McClymont L I 80 McDonald E F 90 McFarlane K W 58 224 Mcfayden J A 80 Mchedlidze G 56 McMahon S J 132 McPherson R A 169 190 Medinnis M 44 Meehan S 139 Mehlhase S 101 Mehta A 76 Meier K 60a Meineck C 101 Meirose B 43 Melini D 167 Mellado Garcia B R 146c Melo M 145a Meloni F 18 Mengarelli A 22a 22b Menke S 102 Meoni E 162 Mergelmeyer S 17 Mermod P 51 Merola L 105a 105b Meroni C 93a Merritt F S 33 Messina A 133a 133b Metcalfe J 6 Mete A S 163 Meyer C 85 Meyer C 123 Meyer J-P 137 Meyer J 108 Meyer Zu Theenhausen H 60a Miano F 150 Middleton R P 132 Miglioranzi S 52a 52b Mijović L 23 Mikenberg G 172 Mikestikova M 128 Mikuž M 77 Milesi M 90 Milic A 64 Miller D W 33 Mills C 48 Milov A 172 Milstead D A 147a 147b Minaenko A A 131 Minami Y 156 Minashvili I A 67 Mincer A I 111 Mindur B 40a Mineev M 67 Ming Y 173 Mir L M 13 Mistry K P 123 Mitani T 171 Mitrevski J 101 Mitsou V A 167 Miucci A 51 Miyagawa P S 140 Mjörnmark J U 83 Moa T 147a 147b Mochizuki K 96 Mohapatra S 37 Molander S 147a 147b Moles-Valls R 23 Monden R 70 Mondragon M C 92 Mönig K 44 Monk J 38 Monnier E 87 Montalbano A 149 Montejo Berlingen J 32 Monticelli F 73 Monzani S 93a 93b Moore R W 3 Morange N 118 Moreno D 21 Moreno Llácer M 56 Morettini P 52a Mori D 143 Mori T 156 Morii M 59 Morinaga M 156 Morisbak V 120 Moritz S 85 Morley A K 151 Mornacchi G 32 Morris J D 78 Mortensen S S 38 Morvaj L 149 Mosidze M 53b Moss J 144 Motohashi K 158 Mount R 144 Mountricha E 27 Mouraviev S V 97 224 Moyse E J W 88 Muanza S 87 Mudd R D 19 Mueller F 102 Mueller J 126 Mueller R S P 101 Mueller T 30 Muenstermann D 74 Mullen P 55 Mullier G A 18 Munoz Sanchez F J 86 Murillo Quijada J A 19 Murray W J 170 132 Musheghyan H 56 Muškinja M 77 Myagkov A G 131 209 Myska M 129 Nachman B P 144 Nackenhorst O 51 Nagai K 121 Nagai R 68 204 Nagano K 68 Nagasaka Y 61 Nagata K 161 Nagel M 50 Nagy E 87 Nairz A M 32 Nakahama Y 32 Nakamura K 68 Nakamura T 156 Nakano I 113 Namasivayam H 43 Naranjo Garcia R F 44 Narayan R 11 Narrias Villar D I 60a Naryshkin I 124 Naumann T 44 Navarro G 21 Nayyar R 7 Neal H A 91 Nechaeva P Yu 97 Neep T J 86 Nef P D 144 Negri A 122a 122b Negrini M 22a Nektarijevic S 107 Nellist C 118 Nelson A 163 Nemecek S 128 Nemethy P 111 Nepomuceno A A 26a Nessi M 32 210 Neubauer M S 166 Neumann M 175 Neves R M 111 Nevski P 27 Newman P R 19 Nguyen D H 6 Nguyen Manh T 96 Nickerson R B 121 Nicolaidou R 137 Nielsen J 138 Nikiforov A 17 Nikolaenko V 131 209 Nikolic-Audit I 82 Nikolopoulos K 19 Nilsen J K 120 Nilsson P 27 Ninomiya Y 156 Nisati A 133a Nisius R 102 Nobe T 156 Nodulman L 6 Nomachi M 119 Nomidis I 31 Nooney T 78 Norberg S 114 Nordberg M 32 Norjoharuddeen N 121 Novgorodova O 46 Nowak S 102 Nozaki M 68 Nozka L 116 Ntekas K 10 Nurse E 80 Nuti F 90 O’grady F 7 O’Neil D C 143 O’Rourke A A 44 O’Shea V 55 Oakham F G 31 182 Oberlack H 102 Obermann T 23 Ocariz J 82 Ochi A 69 Ochoa I 37 Ochoa-Ricoux J P 34a Oda S 72 Odaka S 68 Ogren H 63 Oh A 86 Oh S H 47 Ohm C C 16 Ohman H 165 Oide H 32 Okawa H 161 Okumura Y 33 Okuyama T 68 Olariu A 28b Oleiro Seabra L F 127a Olivares Pino S A 48 Oliveira Damazio D 27 Olszewski A 41 Olszowska J 41 Onofre A 127a 127e Onogi K 104 Onyisi P U E 11 200 Oreglia M J 33 Oren Y 154 Orestano D 135a 135b Orlando N 62b Orr R S 159 Osculati B 52a 52b Ospanov R 86 Otero y Garzon G 29 Otono H 72 Ouchrif M 136d Ould-Saada F 120 Ouraou A 137 Oussoren K P 108 Ouyang Q 35a Owen M 55 Owen R E 19 Ozcan V E 20a Ozturk N 8 Pachal K 143 Pacheco Pages A 13 Padilla Aranda C 13 Pagáčová M 50 Pagan Griso S 16 Paige F 27 Pais P 88 Pajchel K 120 Palacino G 160b Palestini S 32 Palka M 40b Pallin D 36 Palma A 127a 127b Panagiotopoulou E St 10 Pandini C E 82 Panduro Vazquez J G 79 Pani P 147a 147b Panitkin S 27 Pantea D 28b Paolozzi L 51 Papadopoulou Th D 10 Papageorgiou K 155 Paramonov A 6 Paredes Hernandez D 176 Parker A J 74 Parker M A 30 Parker K A 140 Parodi F 52a 52b Parsons J A 37 Parzefall U 50 Pascuzzi V R 159 Pasqualucci E 133a Passaggio S 52a Pastore Fr 79 Pásztor G 31 211 Pataraia S 175 Pater J R 86 Pauly T 32 Pearce J 169 Pearson B 114 Pedersen L E 38 Pedersen M 120 Pedraza Lopez S 167 Pedro R 127a 127b Peleganchuk S V 110 181 Pelikan D 165 Penc O 128 Peng C 35a Peng H 35b Penwell J 63 Peralva B S 26b Perego M M 137 Perepelitsa D V 27 Perez Codina E 160a Perini L 93a 93b Pernegger H 32 Perrella S 105a 105b Peschke R 44 Peshekhonov V D 67 Peters K 44 Peters R F Y 86 Petersen B A 32 Petersen T C 38 Petit E 57 Petridis A 1 Petridou C 155 Petroff P 118 Petrolo E 133a Petrov M 121 Petrucci F 135a 135b Pettersson N E 88 Peyaud A 137 Pezoa R 34b Phillips P W 132 Piacquadio G 144 Pianori E 170 Picazio A 88 Piccaro E 78 Piccinini M 22a 22b Pickering M A 121 Piegaia R 29 Pilcher J E 33 Pilkington A D 86 Pin A W J 86 Pinamonti M 164a 164c 212 Pinfold J L 3 Pingel A 38 Pires S 82 Pirumov H 44 Pitt M 172 Plazak L 145a Pleier M-A 27 Pleskot V 85 Plotnikova E 67 Plucinski P 92 Pluth D 66 Poettgen R 147a 147b Poggioli L 118 Pohl D 23 Polesello G 122a Poley A 44 Policicchio A 39a 39b Polifka R 159 Polini A 22a Pollard C S 55 Polychronakos V 27 Pommès K 32 Pontecorvo L 133a Pope B G 92 Popeneciu G A 28c Popovic D S 14 Poppleton A 32 Pospisil S 129 Potamianos K 16 Potrap I N 67 Potter C J 30 Potter C T 117 Poulard G 32 Poveda J 32 Pozdnyakov V 67 Pozo Astigarraga M E 32 Pralavorio P 87 Pranko A 16 Prell S 66 Price D 86 Price L E 6 Primavera M 75a Prince S 89 Proissl M 48 Prokofiev K 62c Prokoshin F 34b Protopopescu S 27 Proudfoot J 6 Przybycien M 40a Puddu D 135a 135b Purohit M 27 213 Puzo P 118 Qian J 91 Qin G 55 Qin Y 86 Quadt A 56 Quayle W B 164a 164b Queitsch-Maitland M 86 Quilty D 55 Raddum S 120 Radeka V 27 Radescu V 60b Radhakrishnan S K 149 Radloff P 117 Rados P 90 Ragusa F 93a 93b Rahal G 178 Raine J A 86 Rajagopalan S 27 Rammensee M 32 Rangel-Smith C 165 Ratti M G 93a 93b Rauscher F 101 Rave S 85 Ravenscroft T 55 Ravinovich I 172 Raymond M 32 Read A L 120 Readioff N P 76 Reale M 75a 75b Rebuzzi D M 122a 122b Redelbach A 174 Redlinger G 27 Reece R 138 Reeves K 43 Rehnisch L 17 Reichert J 123 Reisin H 29 Rembser C 32 Ren H 35a Rescigno M 133a Resconi S 93a Rezanova O L 110 181 Reznicek P 130 Rezvani R 96 Richter R 102 Richter S 80 Richter-Was E 40b Ricken O 23 Ridel M 82 Rieck P 17 Riegel C J 175 Rieger J 56 Rifki O 114 Rijssenbeek M 149 Rimoldi A 122a 122b Rimoldi M 18 Rinaldi L 22a Ristić B 51 Ritsch E 32 Riu I 13 Rizatdinova F 115 Rizvi E 78 Rizzi C 13 Robertson S H 89 190 Robichaud-Veronneau A 89 Robinson D 30 Robinson J E M 44 Robson A 55 Roda C 125a 125b Rodina Y 87 Rodriguez Perez A 13 Rodriguez Rodriguez D 167 Roe S 32 Rogan C S 59 Røhne O 120 Romaniouk A 99 Romano M 22a 22b Romano Saez S M 36 Romero Adam E 167 Rompotis N 139 Ronzani M 50 Roos L 82 Ros E 167 Rosati S 133a Rosbach K 50 Rose P 138 Rosenthal O 142 Rosien N-A 56 Rossetti V 147a 147b Rossi E 105a 105b Rossi L P 52a Rosten J H N 30 Rosten R 139 Rotaru M 28b Roth I 172 Rothberg J 139 Rousseau D 118 Royon C R 137 Rozanov A 87 Rozen Y 153 Ruan X 146c Rubbo F 144 Rudolph M S 159 Rühr F 50 Ruiz-Martinez A 31 Rurikova Z 50 Rusakovich N A 67 Ruschke A 101 Russell H L 139 Rutherfoord J P 7 Ruthmann N 32 Ryabov Y F 124 Rybar M 166 Rybkin G 118 Ryu S 6 Ryzhov A 131 Rzehorz G F 56 Saavedra A F 151 Sabato G 108 Sacerdoti S 29 Sadrozinski H F-W 138 Sadykov R 67 Safai Tehrani F 133a Saha P 109 Sahinsoy M 60a Saimpert M 137 Saito T 156 Sakamoto H 156 Sakurai Y 171 Salamanna G 135a 135b Salamon A 134a 134b Salazar Loyola J E 34b Salek D 108 Sales De Bruin P H 139 Salihagic D 102 Salnikov A 144 Salt J 167 Salvatore D 39a 39b Salvatore F 150 Salvucci A 62a Salzburger A 32 Sammel D 50 Sampsonidis D 155 Sanchez A 105a 105b Sánchez J 167 Sanchez Martinez V 167 Sandaker H 120 Sandbach R L 78 Sander H G 85 Sandhoff M 175 Sandoval C 21 Sandstroem R 102 Sankey D P C 132 Sannino M 52a 52b Sansoni A 49 Santoni C 36 Santonico R 134a 134b Santos H 127a Santoyo Castillo I 150 Sapp K 126 Sapronov A 67 Saraiva J G 127a 127d Sarrazin B 23 Sasaki O 68 Sasaki Y 156 Sato K 161 Sauvage G 5 224 Sauvan E 5 Savage G 79 Savard P 159 182 Sawyer C 132 Sawyer L 81 195 Saxon J 33 Sbarra C 22a Sbrizzi A 22a 22b Scanlon T 80 Scannicchio D A 163 Scarcella M 151 Scarfone V 39a 39b Schaarschmidt J 172 Schacht P 102 Schachtner B M 101 Schaefer D 32 Schaefer R 44 Schaeffer J 85 Schaepe S 23 Schaetzel S 60b Schäfer U 85 Schaffer A C 118 Schaile D 101 Schamberger R D 149 Scharf V 60a Schegelsky V A 124 Scheirich D 130 Schernau M 163 Schiavi C 52a 52b Schier S 138 Schillo C 50 Schioppa M 39a 39b Schlenker S 32 Schmidt-Sommerfeld K R 102 Schmieden K 32 Schmitt C 85 Schmitt S 44 Schmitz S 85 Schneider B 160a Schnoor U 50 Schoeffel L 137 Schoening A 60b Schoenrock B D 92 Schopf E 23 Schott M 85 Schovancova J 8 Schramm S 51 Schreyer M 174 Schuh N 85 Schultens M J 23 Schultz-Coulon H-C 60a Schulz H 17 Schumacher M 50 Schumm B A 138 Schune Ph 137 Schwartzman A 144 Schwarz T A 91 Schwegler Ph 102 Schweiger H 86 Schwemling Ph 137 Schwienhorst R 92 Schwindling J 137 Schwindt T 23 Sciolla G 25 Scuri F 125a 125b Scutti F 90 Searcy J 91 Seema P 23 Seidel S C 106 Seiden A 138 Seifert F 129 Seixas J M 26a Sekhniaidze G 105a Sekhon K 91 Sekula S J 42 Seliverstov D M 124 224 Semprini-Cesari N 22a 22b Serfon C 120 Serin L 118 Serkin L 164a 164b Sessa M 135a 135b Seuster R 169 Severini H 114 Sfiligoj T 77 Sforza F 32 Sfyrla A 51 Shabalina E 56 Shaikh N W 147a 147b Shan L Y 35a Shang R 166 Shank J T 24 Shapiro M 16 Shatalov P B 98 Shaw K 164a 164b Shaw S M 86 Shcherbakova A 147a 147b Shehu C Y 150 Sherwood P 80 Shi L 152 224 Shimizu S 69 Shimmin C O 163 Shimojima M 103 Shiyakova M 67 215 Shmeleva A 97 Shoaleh Saadi D 96 Shochet M J 33 Shojaii S 93a 93b Shrestha S 112 Shulga E 99 Shupe M A 7 Sicho P 128 Sickles A M 166 Sidebo P E 148 Sidiropoulou O 174 Sidorov D 115 Sidoti A 22a 22b Siegert F 46 Sijacki Dj 14 Silva J 127a 127d Silverstein S B 147a Simak V 129 Simard O 5 Simic Lj 14 Simion S 118 Simioni E 85 Simmons B 80 Simon D 36 Simon M 85 Sinervo P 159 Sinev N B 117 Sioli M 22a 22b Siragusa G 174 Sivoklokov S Yu 100 Sjölin J 147a 147b Sjursen T B 15 Skinner M B 74 Skottowe H P 59 Skubic P 114 Slater M 19 Slavicek T 129 Slawinska M 108 Sliwa K 162 Slovak R 130 Smakhtin V 172 Smart B H 5 Smestad L 15 Smiesko J 145a Smirnov S Yu 99 Smirnov Y 99 Smirnova L N 100 216 Smirnova O 83 Smith M N K 37 Smith R W 37 Smizanska M 74 Smolek K 129 Snesarev A A 97 Snyder S 27 Sobie R 169 190 Socher F 46 Soffer A 154 Soh D A 152 Sokhrannyi G 77 Solans Sanchez C A 32 Solar M 129 Soldatov E Yu 99 Soldevila U 167 Solodkov A A 131 Soloshenko A 67 Solovyanov O V 131 Solovyev V 124 Sommer P 50 Son H 162 Song H Y 35b 217 Sood A 16 Sopczak A 129 Sopko V 129 Sorin V 13 Sosa D 60b Sotiropoulou C L 125a 125b Soualah R 164a 164c Soukharev A M 110 181 South D 44 Sowden B C 79 Spagnolo S 75a 75b Spalla M 125a 125b Spangenberg M 170 Spanò F 79 Sperlich D 17 Spettel F 102 Spighi R 22a Spigo G 32 Spiller L A 90 Spousta M 130 St  Denis R D 55 224 Stabile A 93a Stamen R 60a Stamm S 17 Stanecka E 41 Stanek R W 6 Stanescu C 135a Stanescu-Bellu M 44 Stanitzki M M 44 Stapnes S 120 Starchenko E A 131 Stark G H 33 Stark J 57 Staroba P 128 Starovoitov P 60a Stärz S 32 Staszewski R 41 Steinberg P 27 Stelzer B 143 Stelzer H J 32 Stelzer-Chilton O 160a Stenzel H 54 Stewart G A 55 Stillings J A 23 Stockton M C 89 Stoebe M 89 Stoicea G 28b Stolte P 56 Stonjek S 102 Stradling A R 8 Straessner A 46 Stramaglia M E 18 Strandberg J 148 Strandberg S 147a 147b Strandlie A 120 Strauss M 114 Strizenec P 145b Ströhmer R 174 Strom D M 117 Stroynowski R 42 Strubig A 107 Stucci S A 18 Stugu B 15 Styles N A 44 Su D 144 Su J 126 Subramaniam R 81 Suchek S 60a Sugaya Y 119 Suk M 129 Sulin V V 97 Sultansoy S 4c Sumida T 70 Sun S 59 Sun X 35a Sundermann J E 50 Suruliz K 150 Susinno G 39a 39b Sutton M R 150 Suzuki S 68 Svatos M 128 Swiatlowski M 33 Sykora I 145a Sykora T 130 Ta D 50 Taccini C 135a 135b Tackmann K 44 Taenzer J 159 Taffard A 163 Tafirout R 160a Taiblum N 154 Takai H 27 Takashima R 71 Takeshita T 141 Takubo Y 68 Talby M 87 Talyshev A A 110 181 Tan K G 90 Tanaka J 156 Tanaka R 118 Tanaka S 68 Tannenwald B B 112 Tapia Araya S 34b Tapprogge S 85 Tarem S 153 Tartarelli G F 93a Tas P 130 Tasevsky M 128 Tashiro T 70 Tassi E 39a 39b Tavares Delgado A 127a 127b Tayalati Y 136d Taylor A C 106 Taylor G N 90 Taylor P T E 90 Taylor W 160b Teischinger F A 32 Teixeira-Dias P 79 Temming K K 50 Temple D 143 Ten Kate H 32 Teng P K 152 Teoh J J 119 Tepel F 175 Terada S 68 Terashi K 156 Terron J 84 Terzo S 102 Testa M 49 Teuscher R J 159 190 Theveneaux-Pelzer T 87 Thomas J P 19 Thomas-Wilsker J 79 Thompson E N 37 Thompson P D 19 Thompson A S 55 Thomsen L A 176 Thomson E 123 Thomson M 30 Tibbetts M J 16 Ticse Torres R E 87 Tikhomirov V O 97 218 Tikhonov Yu A 110 181 Timoshenko S 99 Tipton P 176 Tisserant S 87 Todome K 158 Todorov T 5 224 Todorova-Nova S 130 Tojo J 72 Tokár S 145a Tokushuku K 68 Tolley E 59 Tomlinson L 86 Tomoto M 104 Tompkins L 144 219 Toms K 106 Tong B 59 Torrence E 117 Torres H 143 Torró Pastor E 139 Toth J 87 220 Touchard F 87 Tovey D R 140 Trefzger T 174 Tricoli A 27 Trigger I M 160a Trincaz-Duvoid S 82 Tripiana M F 13 Trischuk W 159 Trocmé B 57 Trofymov A 44 Troncon C 93a Trottier-McDonald M 16 Trovatelli M 169 Truong L 164a 164c Trzebinski M 41 Trzupek A 41 Tseng J C-L 121 Tsiareshka P V 94 Tsipolitis G 10 Tsirintanis N 9 Tsiskaridze S 13 Tsiskaridze V 50 Tskhadadze E G 53a Tsui K M 62a Tsukerman I I 98 Tsulaia V 16 Tsuno S 68 Tsybychev D 149 Tudorache A 28b Tudorache V 28b Tuna A N 59 Tupputi S A 22a 22b Turchikhin S 100 216 Turecek D 129 Turgeman D 172 Turra R 93a 93b Turvey A J 42 Tuts P M 37 Tyndel M 132 Ucchielli G 22a 22b Ueda I 156 Ueno R 31 Ughetto M 147a 147b Ukegawa F 161 Unal G 32 Undrus A 27 Unel G 163 Ungaro F C 90 Unno Y 68 Unverdorben C 101 Urban J 145b Urquijo P 90 Urrejola P 85 Usai G 8 Usanova A 64 Vacavant L 87 Vacek V 129 Vachon B 89 Valderanis C 101 Valdes Santurio E 147a 147b Valencic N 108 Valentinetti S 22a 22b Valero A 167 Valery L 13 Valkar S 130 Vallecorsa S 51 Valls Ferrer J A 167 Van Den Wollenberg W 108 Van Der Deijl P C 108 van der Geer R 108 van der Graaf H 108 van Eldik N 153 van Gemmeren P 6 Van Nieuwkoop J 143 van Vulpen I 108 van Woerden M C 32 Vanadia M 133a 133b Vandelli W 32 Vanguri R 123 Vaniachine A 131 Vankov P 108 Vardanyan G 177 Vari R 133a Varnes E W 7 Varol T 42 Varouchas D 82 Vartapetian A 8 Varvell K E 151 Vasquez J G 176 Vazeille F 36 Vazquez Schroeder T 89 Veatch J 56 Veloce L M 159 Veloso F 127a 127c Veneziano S 133a Ventura A 75a 75b Venturi M 169 Venturi N 159 Venturini A 25 Vercesi V 122a Verducci M 133a 133b Verkerke W 108 Vermeulen J C 108 Vest A 46 221 Vetterli M C 143 182 Viazlo O 83 Vichou I 166 Vickey T 140 Vickey Boeriu O E 140 Viehhauser G H A 121 Viel S 16 Vigani L 121 Vigne R 64 Villa M 22a 22b Villaplana Perez M 93a 93b Vilucchi E 49 Vincter M G 31 Vinogradov V B 67 Vittori C 22a 22b Vivarelli I 150 Vlachos S 10 Vlasak M 129 Vogel M 175 Vokac P 129 Volpi G 125a 125b Volpi M 90 von der Schmitt H 102 von Toerne E 23 Vorobel V 130 Vorobev K 99 Vos M 167 Voss R 32 Vossebeld J H 76 Vranjes N 14 Vranjes Milosavljevic M 14 Vrba V 128 Vreeswijk M 108 Vuillermet R 32 Vukotic I 33 Vykydal Z 129 Wagner P 23 Wagner W 175 Wahlberg H 73 Wahrmund S 46 Wakabayashi J 104 Walder J 74 Walker R 101 Walkowiak W 142 Wallangen V 147a 147b Wang C 35c Wang C 35d 87 Wang F 173 Wang H 16 Wang H 42 Wang J 44 Wang J 151 Wang K 89 Wang R 6 Wang S M 152 Wang T 23 Wang T 37 Wang W 35b Wang X 176 Wanotayaroj C 117 Warburton A 89 Ward C P 30 Wardrope D R 80 Washbrook A 48 Watkins P M 19 Watson A T 19 Watson M F 19 Watts G 139 Watts S 86 Waugh B M 80 Webb S 85 Weber M S 18 Weber S W 174 Webster J S 6 Weidberg A R 121 Weinert B 63 Weingarten J 56 Weiser C 50 Weits H 108 Wells P S 32 Wenaus T 27 Wengler T 32 Wenig S 32 Wermes N 23 Werner M 50 Werner M D 66 Werner P 32 Wessels M 60a Wetter J 162 Whalen K 117 Whallon N L 139 Wharton A M 74 White A 8 White M J 1 White R 34b Whiteson D 163 Wickens F J 132 Wiedenmann W 173 Wielers M 132 Wienemann P 23 Wiglesworth C 38 Wiik-Fuchs L A M 23 Wildauer A 102 Wilk F 86 Wilkens H G 32 Williams H H 123 Williams S 108 Willis C 92 Willocq S 88 Wilson J A 19 Wingerter-Seez I 5 Winklmeier F 117 Winston O J 150 Winter B T 23 Wittgen M 144 Wittkowski J 101 Wollstadt S J 85 Wolter M W 41 Wolters H 127a 127c Wosiek B K 41 Wotschack J 32 Woudstra M J 86 Wozniak K W 41 Wu M 57 Wu M 33 Wu S L 173 Wu X 51 Wu Y 91 Wyatt T R 86 Wynne B M 48 Xella S 38 Xu D 35a Xu L 27 Yabsley B 151 Yacoob S 146a Yakabe R 69 Yamaguchi D 158 Yamaguchi Y 119 Yamamoto A 68 Yamamoto S 156 Yamanaka T 156 Yamauchi K 104 Yamazaki Y 69 Yan Z 24 Yang H 35e 35f Yang H 173 Yang Y 152 Yang Z 15 Yao W-M 16 Yap Y C 82 Yasu Y 68 Yatsenko E 5 Yau Wong K H 23 Ye J 42 Ye S 27 Yeletskikh I 67 Yen A L 59 Yildirim E 85 Yorita K 171 Yoshida R 6 Yoshihara K 123 Young C 144 Young C J S 32 Youssef S 24 Yu D R 16 Yu J 8 Yu J M 91 Yu J 66 Yuan L 69 Yuen S P Y 23 Yusuff I 30 222 Zabinski B 41 Zaidan R 35d Zaitsev A M 131 209 Zakharchuk N 44 Zalieckas J 15 Zaman A 149 Zambito S 59 Zanello L 133a 133b Zanzi D 90 Zeitnitz C 175 Zeman M 129 Zemla A 40a Zeng J C 166 Zeng Q 144 Zengel K 25 Zenin O 131 Ženiš T 145a Zerwas D 118 Zhang D 91 Zhang F 173 Zhang G 35b 217 Zhang H 35c Zhang J 6 Zhang L 50 Zhang R 23 Zhang R 35b 223 Zhang X 35d Zhang Z 118 Zhao X 42 Zhao Y 35d Zhao Z 35b Zhemchugov A 67 Zhong J 121 Zhou B 91 Zhou C 47 Zhou L 37 Zhou L 42 Zhou M 149 Zhou N 35g Zhu C G 35d Zhu H 35a Zhu J 91 Zhu Y 35b Zhuang X 35a Zhukov K 97 Zibell A 174 Zieminska D 63 Zimine N I 67 Zimmermann C 85 Zimmermann S 50 Zinonos Z 56 Zinser M 85 Ziolkowski M 142 Živković L 14 Zobernig G 173 Zoccoli A 22a 22b zur Nedden M 17 Zurzolo G 105a 105b Zwalinski L 32 1Department of Physics, University of Adelaide, Adelaide, Australia 2Physics Department, SUNY Albany, Albany NY, USA 3Department of Physics, University of Alberta, Edmonton AB, Canada 4aDepartment of Physics, Ankara University, Ankara 4b Istanbul Aydin University, Istanbul 4cDivision of Physics, TOBB University of Economics and Technology, Ankara, Turkey 5LAPP, CNRS/IN2P3 and Université Savoie Mont Blanc, Annecy-le-Vieux, France 6High Energy Physics Division, Argonne National Laboratory, Argonne IL, USA 7Department of Physics, University of Arizona, Tucson AZ, USA 8Department of Physics, The University of Texas at Arlington, Arlington TX, USA 9Physics Department, University of Athens, Athens, Greece 10Physics Department, National Technical University of Athens, Zografou, Greece 11Department of Physics, The University of Texas at Austin, Austin TX, USA 12Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan 13Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Barcelona, Spain 14Institute of Physics, University of Belgrade, Belgrade, Serbia 15Department for Physics and Technology, University of Bergen, Bergen, Norway 16Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley CA, USA 17Department of Physics, Humboldt University, Berlin, Germany 18Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, University of Bern, Bern, Switzerland 19School of Physics and Astronomy, University of Birmingham, Birmingham, UK 20aDepartment of Physics, Bogazici University, Istanbul 20bDepartment of Physics Engineering, Gaziantep University, Gaziantep, Turkey 20d Istanbul Bilgi University, Faculty of Engineering and Natural Sciences, Istanbul, Turkey 20e Bahcesehir University, Faculty of Engineering and Natural Sciences, Istanbul, Turkey 21Centro de Investigaciones, Universidad Antonio Narino, Bogota, Colombia 22aINFN Sezione di Bologna, Italy 22bDipartimento di Fisica e Astronomia, Università di Bologna, Bologna, Italy 23Physikalisches Institut, University of Bonn, Bonn, Germany 24Department of Physics, Boston University, Boston MA, USA 25Department of Physics, Brandeis University, Waltham MA, USA 26a Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro, Brazil 26bElectrical Circuits Department, Federal University of Juiz de Fora (UFJF), Juiz de Fora, Brazil 26c Federal University of Sao Joao del Rei (UFSJ), Sao Joao del Rei, Brazil 26dInstituto de Fisica, Universidade de Sao Paulo, Sao Paulo, Brazil 27Physics Department, Brookhaven National Laboratory, Upton NY, USA 28a Transilvania University of Brasov, Brasov, Romania 28bNational Institute of Physics and Nuclear Engineering, Bucharest, Romania 28cNational Institute for Research and Development of Isotopic and Molecular Technologies, Physics Department, Cluj Napoca, Romania 28dUniversity Politehnica Bucharest, Bucharest, Romania 28eWest University in Timisoara, Timisoara, Romania 29Departamento de Física, Universidad de Buenos Aires, Buenos Aires, Argentina 30Cavendish Laboratory, University of Cambridge, Cambridge, UK 31Department of Physics, Carleton University, Ottawa ON, Canada 32CERN, Geneva, Switzerland 33Enrico Fermi Institute, University of Chicago, Chicago IL, USA 34aDepartamento de Física, Pontificia Universidad Católica de Chile, Santiago, Chile 34bDepartamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile 35aInstitute of High Energy Physics, Chinese Academy of Sciences, Beijing, People’s Republic of China 35bDepartment of Modern Physics, University of Science and Technology of China, Anhui, People’s Republic of China 35cDepartment of Physics, Nanjing University, Jiangsu, People’s Republic of China 35dSchool of Physics, Shandong University, Shandong, People’s Republic of China 35eDepartment of Physics and Astronomy, Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai Jiao Tong University, Shanghai, People’s Republic of China 35fAlso affiliated with PKU-CHEP 35gPhysics Department, Tsinghua University, Beijing 100084, People’s Republic of China 36Laboratoire de Physique Corpusculaire, Clermont Université and Université Blaise Pascal and CNRS/IN2P3, Clermont-Ferrand, France 37Nevis Laboratory, Columbia University, Irvington NY, USA 38Niels Bohr Institute, University of Copenhagen, Kobenhavn, Denmark 39aINFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati, Italy 39bDipartimento di Fisica, Università della Calabria, Rende, Italy 40a AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Krakow, Poland 40bMarian Smoluchowski Institute of Physics, Jagiellonian University, Krakow, Poland 41 Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland 42Physics Department, Southern Methodist University, Dallas TX, USA 43Physics Department, University of Texas at Dallas, Richardson TX, USA 44DESY, Hamburg and Zeuthen, Germany 45Institut für Experimentelle Physik IV, Technische Universität Dortmund, Dortmund, Germany 46Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden, Germany 47Department of Physics, Duke University, Durham NC, USA 48SUPA—School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK 49INFN Laboratori Nazionali di Frascati, Frascati, Italy 50Fakultät für Mathematik und Physik, Albert-Ludwigs-Universität, Freiburg, Germany 51Section de Physique, Université de Genève, Geneva, Switzerland 52aINFN Sezione di Genova, Italy 52bDipartimento di Fisica, Università di Genova, Genova, Italy 53aE. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi, Georgia 53bHigh Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia 54II Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany 55SUPA—School of Physics and Astronomy, University of Glasgow, Glasgow, UK 56II Physikalisches Institut, Georg-August-Universität, Göttingen, Germany 57Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3, Grenoble, France 58Department of Physics, Hampton University, Hampton VA, USA 59Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge MA, USA 60aKirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 60bPhysikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 60cZITI Institut für technische Informatik, Ruprecht-Karls-Universität Heidelberg, Mannheim, Germany 61Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima, Japan 62aDepartment of Physics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, People’s Republic of China 62bDepartment of Physics, The University of Hong Kong, Hong Kong, People’s Republic of China 62cDepartment of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People’s Republic of China 63Department of Physics, Indiana University, Bloomington IN, USA 64Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria 65 University of Iowa, Iowa City IA, USA 66Department of Physics and Astronomy, Iowa State University, Ames IA, USA 67 Joint Institute for Nuclear Research, JINR Dubna, Dubna, Russia 68KEK, High Energy Accelerator Research Organization, Tsukuba, Japan 69Graduate School of Science, Kobe University, Kobe, Japan 70Faculty of Science, Kyoto University, Kyoto, Japan 71 Kyoto University of Education, Kyoto, Japan 72Department of Physics, Kyushu University, Fukuoka, Japan 73Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina 74Physics Department, Lancaster University, Lancaster, UK 75aINFN Sezione di Lecce, Italy 75bDipartimento di Matematica e Fisica, Università del Salento, Lecce, Italy 76Oliver Lodge Laboratory, University of Liverpool, Liverpool, UK 77Department of Physics, Jožef Stefan Institute and University of Ljubljana, Ljubljana, Slovenia 78School of Physics and Astronomy, Queen Mary University of London, London, UK 79Department of Physics, Royal Holloway University of London, Surrey, UK 80Department of Physics and Astronomy,University College London, London, UK 81 Louisiana Tech University, Ruston LA, USA 82Laboratoire de Physique Nucléaire et de Hautes Energies, UPMC and Université Paris-Diderot and CNRS/IN2P3, Paris, France 83Fysiska institutionen, Lunds universitet, Lund, Sweden 84Departamento de Fisica Teorica C-15, Universidad Autonoma de Madrid, Madrid, Spain 85Institut für Physik, Universität Mainz, Mainz, Germany 86School of Physics and Astronomy, University of Manchester, Manchester, UK 87CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, France 88Department of Physics, University of Massachusetts, Amherst MA, USA 89Department of Physics, McGill University, Montreal QC, Canada 90School of Physics, University of Melbourne, Victoria, Australia 91Department of Physics, The University of Michigan, Ann Arbor MI, USA 92Department of Physics and Astronomy, Michigan State University, East Lansing MI, USA 93aINFN Sezione di Milano, Italy 93bDipartimento di Fisica, Università di Milano, Milano, Italy 94B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, Republic of Belarus 95National Scientific and Educational Centre for Particle and High Energy Physics, Minsk, Republic of Belarus 96Group of Particle Physics, University of Montreal, Montreal QC, Canada 97 P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, Russia 98 Institute for Theoretical and Experimental Physics (ITEP), Moscow, Russia 99 National Research Nuclear University MEPhI, Moscow, Russia 100D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow, Russia 101Fakultät für Physik, Ludwig-Maximilians-Universität München, München, Germany 102 Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München, Germany 103 Nagasaki Institute of Applied Science, Nagasaki, Japan 104Graduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya, Japan 105aINFN Sezione di Napoli, Italy 105bDipartimento di Fisica, Università di Napoli, Napoli, Italy 106Department of Physics and Astronomy, University of New Mexico, Albuquerque NM, USA 107Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen, The Netherlands 108 Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, The Netherlands 109Department of Physics, Northern Illinois University, DeKalb IL, USA 110 Budker Institute of Nuclear Physics, SB RAS, Novosibirsk, Russia 111Department of Physics, New York University, New York NY, USA 112 Ohio State University, Columbus OH, USA 113Faculty of Science, Okayama University, Okayama, Japan 114Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman OK, USA 115Department of Physics, Oklahoma State University, Stillwater OK, USA 116 Palacký University, RCPTM, Olomouc, Czech Republic 117Center for High Energy Physics, University of Oregon, Eugene OR, USA 118LAL, Univ. Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay, France 119Graduate School of Science, Osaka University, Osaka, Japan 120Department of Physics, University of Oslo, Oslo, Norway 121Department of Physics, Oxford University, Oxford, UK 122aINFN Sezione di Pavia, Italy 122bDipartimento di Fisica, Università di Pavia, Pavia, Italy 123Department of Physics, University of Pennsylvania, Philadelphia PA, USA 124National Research Centre ‘Kurchatov Institute’ B.P.Konstantinov Petersburg Nuclear Physics Institute, St. Petersburg, Russia 125aINFN Sezione di Pisa, Italy 125bDipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy 126Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh PA, USA 127aLaboratório de Instrumentação e Física Experimental de Partículas—LIP, Lisboa, Portugal 127bFaculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal 127cDepartment of Physics, University of Coimbra, Coimbra, Portugal 127d Centro de Física Nuclear da Universidade de Lisboa, Lisboa, Portugal 127eDepartamento de Fisica, Universidade do Minho, Braga, Portugal 127fDepartamento de Fisica Teorica y del Cosmos and CAFPE, Universidad de Granada, Granada, Spain 127gDep Fisica and CEFITEC of Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal 128 Institute of Physics, Academy of Sciences of the Czech Republic, Praha, Czech Republic 129 Czech Technical University in Prague, Praha, Czech Republic 130Faculty of Mathematics and Physics, Charles University in Prague, Praha, Czech Republic 131 State Research Center Institute for High Energy Physics (Protvino), NRC KI, Russia 132Particle Physics Department, Rutherford Appleton Laboratory, Didcot, UK 133aINFN Sezione di Roma, Italy 133bDipartimento di Fisica, Sapienza Università di Roma, Roma, Italy 134aINFN Sezione di Roma Tor Vergata, Italy 134bDipartimento di Fisica, Università di Roma Tor Vergata, Roma, Italy 135aINFN Sezione di Roma Tre, Italy 135bDipartimento di Matematica e Fisica, Università Roma Tre, Roma, Italy 136aFaculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies—Université Hassan II, Casablanca, Morocco 136bCentre National de l’Energie des Sciences Techniques Nucleaires, Rabat, Morocco 136cFaculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA-Marrakech, Morocco 136dFaculté des Sciences, Université Mohamed Premier and LPTPM, Oujda, Morocco 136eFaculté des sciences, Université Mohammed V, Rabat, Morocco 137DSM/IRFU (Institut de Recherches sur les Lois Fondamentales de l’Univers), CEA Saclay (Commissariat à l’Energie Atomique et aux Energies Alternatives), Gif-sur-Yvette, France 138Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz CA, USA 139Department of Physics, University of Washington, Seattle WA, USA 140Department of Physics and Astronomy, University of Sheffield, Sheffield, UK 141Department of Physics, Shinshu University, Nagano, Japan 142Fachbereich Physik, Universität Siegen, Siegen, Germany 143Department of Physics, Simon Fraser University, Burnaby BC, Canada 144SLAC National Accelerator Laboratory, Stanford CA, USA 145aFaculty of Mathematics, Physics & Informatics, Comenius University, Bratislava, Slovakia 145bDepartment of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences, Kosice, Slovak Republic, Slovakia 146aDepartment of Physics, University of Cape Town, Cape Town, South Africa 146bDepartment of Physics, University of Johannesburg, Johannesburg, South Africa 146cSchool of Physics, University of the Witwatersrand, Johannesburg, South Africa 147a Department of Physics, Stockholm University, Sweden 147b The Oskar Klein Centre, Stockholm, Sweden 148Physics Department, Royal Institute of Technology, Stockholm, Sweden 149Departments of Physics & Astronomy and Chemistry, Stony Brook University, Stony Brook NY, USA 150Department of Physics and Astronomy, University of Sussex, Brighton, UK 151School of Physics, University of Sydney, Sydney, Australia 152 Institute of Physics, Academia Sinica, Taipei, Taiwan 153Department of Physics, Technion: Israel Institute of Technology, Haifa, Israel 154Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel 155Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece 156International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan 157Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan 158Department of Physics, Tokyo Institute of Technology, Tokyo, Japan 159Department of Physics, University of Toronto, Toronto ON, Canada 160aTRIUMF, Vancouver BC, Canada 160bDepartment of Physics and Astronomy, York University, Toronto ON, Canada 161Faculty of Pure and Applied Sciences, and Center for Integrated Research in Fundamental Science and Engineering, University of Tsukuba, Tsukuba, Japan 162Department of Physics and Astronomy, Tufts University, Medford MA, USA 163Department of Physics and Astronomy, University of California Irvine, Irvine CA, USA 164a INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy 164bICTP, Trieste, Italy 164cDipartimento di Chimica, Fisica e Ambiente, Università di Udine, Udine, Italy 165Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden 166Department of Physics, University of Illinois, Urbana IL, USA 167Instituto de Fisica Corpuscular (IFIC) and Departamento de Fisica Atomica, Molecular y Nuclear and Departamento de Ingeniería Electrónica and Instituto de Microelectrónica de Barcelona (IMB-CNM), University of Valencia and CSIC, Valencia, Spain 168Department of Physics, University of British Columbia, Vancouver BC, Canada 169Department of Physics and Astronomy, University of Victoria, Victoria BC, Canada 170Department of Physics, University of Warwick, Coventry, UK 171 Waseda University, Tokyo, Japan 172Department of Particle Physics, The Weizmann Institute of Science, Rehovot, Israel 173Department of Physics, University of Wisconsin, Madison WI, USA 174Fakultät für Physik und Astronomie, Julius-Maximilians-Universität, Würzburg, Germany 175Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany 176Department of Physics, Yale University, New Haven CT, USA 177 Yerevan Physics Institute, Yerevan, Armenia 178 Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), Villeurbanne, France 179Also at Department of Physics, King's College London, London, UK 180Also at Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan 181Also at Novosibirsk State University, Novosibirsk, Russia 182Also at TRIUMF, Vancouver BC, Canada 183Also at Department of Physics & Astronomy, University of Louisville, Louisville, KY, USA 184Also at Department of Physics, California State University, Fresno CA, USA 185Also at Department of Physics, University of Fribourg, Fribourg, Switzerland 186Also at Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona, Spain 187Also at Departamento de Fisica e Astronomia, Faculdade de Ciencias, Universidade do Porto, Portugal 188Also at Tomsk State University, Tomsk, Russia 189Also at Universita di Napoli Parthenope, Napoli, Italy 190Also at Institute of Particle Physics (IPP), Canada 191Also at National Institute of Physics and Nuclear Engineering, Bucharest, Romania 192Also at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia 193Also at Department of Physics, The University of Michigan, Ann Arbor MI, USA 194Also at Centre for High Performance Computing, CSIR Campus, Rosebank, Cape Town, South Africa 195Also at Louisiana Tech University, Ruston LA, USA 196Also at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spain 197Also at Graduate School of Science, Osaka University, Osaka, Japan 198Also at Department of Physics, National Tsing Hua University, Taiwan 199Also at Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen, The Netherlands 200Also at Department of Physics, The University of Texas at Austin, Austin TX, USA 201Also at Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia 202Also at CERN, Geneva, Switzerland 203Also at Georgian Technical University (GTU),Tbilisi, Georgia 204Also at Ochadai Academic Production, Ochanomizu University, Tokyo, Japan 205Also at Manhattan College, New York NY, USA 206Also at Hellenic Open University, Patras, Greece 207Also at Academia Sinica Grid Computing, Institute of Physics, Academia Sinica, Taipei, Taiwan 208Also at School of Physics, Shandong University, Shandong, People’s Republic of China 209Also at Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia 210Also at section de Physique, Université de Genève, Geneva, Switzerland 211Also at Eotvos Lorand University, Budapest, Hungary 212Also at International School for Advanced Studies (SISSA), Trieste, Italy 213Also at Department of Physics and Astronomy, University of South Carolina, Columbia SC, USA 214Also at School of Physics and Engineering, Sun Yat-sen University, Guangzhou, People’s Republic of China 215Also at Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Sofia, Bulgaria 216Also at Faculty of Physics, M.V.Lomonosov Moscow State University, Moscow, Russia 217Also at Institute of Physics, Academia Sinica, Taipei, Taiwan 218Also at National Research Nuclear University MEPhI, Moscow, Russia 219Also at Department of Physics, Stanford University, Stanford CA, USA 220Also at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest, Hungary 221Also at Flensburg University of Applied Sciences, Flensburg, Germany 222Also at University of Malaya, Department of Physics, Kuala Lumpur, Malaysia 223Also at CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, France 224Deceased

M Aaboud et al

9 2016 07 09 2016 07 09 2016 18 9 093016 20 5 2016 15 7 2016 2 8 2016 20 5 2016 © 2016 CERN for the benefit of the ATLAS Collaboration 2016 Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

An inclusive search for a new-physics signature of lepton-jet resonances has been performed by the ATLAS experiment. Scalar leptoquarks, pair-produced in pp collisions at s  = 13 TeV at the large hadron collider, have been considered. An integrated luminosity of 3.2 fb⁻¹, corresponding to the full 2015 dataset was used. First (second) generation leptoquarks were sought in events with two electrons (muons) and two or more jets. The observed event yield in each channel is consistent with Standard Model background expectations. The observed (expected) lower limits on the leptoquark mass at 95% confidence level are 1100 and 1050 GeV (1160 and 1040 GeV) for first and second generation leptoquarks, respectively, assuming a branching ratio into a charged lepton and a quark of 100%. Upper limits on the aforementioned branching ratio are also given as a function of leptoquark mass. Compared with the results of earlier ATLAS searches, the sensitivity is increased for leptoquark masses above 860 GeV, and the observed exclusion limits confirm and extend the published results.

leptoquark ATLAS LHC Please see acknowledgements section of paper

Article funded by SCOAP³.

ccc 1367-2630/16/093016+25$33.00 crossmark yes 1.

The large hadron collider (LHC) Run 2 has provided the possibility to study pp collisions at 13 TeV centre-of-mass energy for the first time, and has thus opened a new discovery window for physics beyond the standard model (SM). The presented analysis is an inclusive search for new physics phenomena resulting in final state signatures of lepton-jet resonances in the first 3.2 fb⁻¹ of 13 TeV data collected by the ATLAS detector. Such phenomena may not have been kinematically accessible at the lower Run 1 centre-of-mass energy of 8 TeV. As a benchmark signal model, scalar leptoquarks decaying to jets and leptons were used.

Leptoquarks (LQs) feature in a number of theories [1–7] which extend the SM, such as grand unified theories and models with quark and lepton substructure. LQs possess non-zero baryon and lepton numbers and their existence would provide a connection between quarks and leptons. This could help explain the observed similarity of the quark and lepton sectors in the SM. LQs carry a colour-triplet charge and a fractional electric charge [8]. They can be scalar or vector bosons and they decay directly to lepton–quark pairs. The analysis presented in this paper focuses on the pair production of scalar leptoquarks.

A single Yukawa coupling ( λ ℓ ) governs the interaction strength between a scalar LQ and a given quark (q) and lepton (ℓ) pair. A Feynman diagram showing a LQ decay is shown in figure 1. The couplings are determined by two free parameters of the model: the branching ratio into charged leptons, β, and the coupling parameter, λ. The coupling to a charged lepton and a quark is given by λ ℓ = β λ , the coupling to a neutrino and a quark by λ ν = 1 − β λ . The pair-production cross section of leptoquarks in pp collisions is largely insensitive to the coupling values, since the basic processes of LQ pair-production are gluon fusion and quark–antiquark annihilation. Example LO diagrams are shown in figure 2. At a centre-of-mass energy of s = 13 TeV, gluon fusion is the dominant process. For LQ masses (m_LQ) up to a few hundred GeV, it contributes up to 95% of the total cross section. Above m_LQ = 1.5 TeV, the contribution from quark–antiquark annihilation amounts to about 30% [9]. Therefore, the parameter of interest — apart from the LQ mass — is the branching ratio β.

Figure 1.

Feynman diagram showing the Yukawa coupling λ ℓ = β λ between a leptoquark, a lepton (ℓ) and a quark (q).

Figure 2.

Dominant leading-order Feynman diagrams for the pair production of scalar leptoquarks from gluon fusion and quark–antiquark annihilation.

The signal benchmark model for LQ production used in this analysis is the minimal Buchmüller–Rückl–Wyler model (mBRW) [10]. In this approach a number of constraints are imposed on the LQ properties. Lepton number and baryon number are separately conserved to prevent fast proton decay. The LQ couplings are also considered to be purely chiral. Furthermore, it is assumed that LQs belong to three generations (first, second and third) which interact only with lepton–quark pairs within the same generation. With this assumption, lepton-flavour violation is suppressed. However, in a more generic picture of leptoquarks, a LQ may couple to a quark and a lepton belonging to different generations [11]. Although the results of this search were not explicitly interpreted in this type of model, the event selections used were designed to retain sensitivity to leptoquark models in which decays into first or second generation leptons and bottom-quarks (b) are possible.

Previous searches for pair-produced LQs have been performed by the ATLAS and CMS collaborations [12–24] at s  = 7 and 8 TeV. The existence of scalar LQs with masses up to 1050 and 1000 GeV (for β = 1 ) for first- and second-generation scalar LQs, respectively, is excluded at 95% confidence level (CL) by ATLAS [20] in a study performed at s =8 TeV using 20 fb⁻¹ of integrated luminosity. The CMS experiment similarly excluded first- and second-generation scalar leptoquarks up to masses of 1010 GeV and 1080 GeV (for β = 1 ), respectively [21].

In this paper, searches for the pair-production of leptoquarks of the first (LQ1) and second (LQ2) generations, based on events containing exactly two electrons or muons and at least two jets (denoted by eejj and μ μ jj , respectively), are reported. In order to keep the search as inclusive as possible, it was not required that the charges of the two leptons in an event must be opposite. Similarly, no selections on the jet flavour were introduced so as not to exclude possible LQ → eb and LQ → μ b decays.

2.

The ATLAS experiment [25] is a multi-purpose detector with a forward-backward symmetric cylindrical geometry and nearly 4π coverage in solid angle^{225 225}

ATLAS uses a right-handed coordinate system with its origin at the nominal interaction point (IP) in the centre of the detector and the z-axis along the beam pipe. The x-axis points from the IP to the centre of the LHC ring, and the y-axis points upward. Cylindrical coordinates ( r , ϕ ) are used in the transverse plane, ϕ being the azimuthal angle around the z-axis. The pseudorapidity is defined in terms of the polar angle θ as η = − ln tan ( θ / 2 ) .

. The three major sub-components of ATLAS are the tracking detector, the calorimeter and the muon spectrometer (MS). Charged-particle tracks and vertices are reconstructed by the inner detector (ID) tracking system, comprising silicon pixel (including the newly installed innermost pixel layer), and microstrip detectors covering the pseudorapidity range ∣ η ∣ < 2.5, and a straw tube tracker that covers ∣ η ∣ < 2.0. The ID is immersed in a homogeneous 2 T magnetic field provided by a solenoid. Electron, photon, jet and τ lepton energies are measured with sampling calorimeters. The ATLAS calorimeter system covers a pseudorapidity range of ∣ η ∣ < 4.9. Within the region ∣ η ∣ < 3.2, electromagnetic calorimetry is provided by barrel and endcap high-granularity lead/liquid argon (LAr) calorimeters, with an additional thin LAr presampler covering ∣ η ∣ < 1.8, to correct for energy loss in material upstream of the calorimeters. Hadronic calorimetry is provided by a steel/scintillator-tile calorimeter, segmented into three barrel structures within ∣ η ∣ < 1.7, and two copper/LAr hadronic endcap calorimeters. The forward region (3.1 < ∣ η ∣ < 4.9) is instrumented by a LAr calorimeter with copper (electromagnetic) and tungsten (hadronic) absorbers. Surrounding the calorimeters is a MS with superconducting air-core toroids, providing bending powers of 3 Tm in the barrel and 6 Tm in the endcaps. The MS includes a system of precision tracking chambers providing coverage over ∣ η ∣ < 2.7. Three stations of precision tracking chambers are used to measure the curvature of tracks. The MS also contains detectors with triggering capabilities over ∣ η ∣ < 2.4 to provide fast muon identification and momentum measurements.

The ATLAS two-level trigger system is used to select events considered in this paper. The first-level trigger is hardware-based while the second, high-level trigger is implemented in software and employs algorithms similar to those used offline in the full event reconstruction.

3.

The Pythia 8.160 [26] Monte Carlo (MC) model, based on leading-order (LO) matrix-element calculations supplemented with parton showers, was used with the ATLASA14 [27] set of tuned parameters (tune) for the underlying event, together with the NNPDF23LO [28] parton distribution functions (PDFs), to produce simulated samples of pair-produced first- and second-generation scalar LQs. Leptoquarks of the first (second) generation decay to e + e − u u ¯ ( μ + μ − c c ¯ ) final states. Samples were produced for LQ masses in the range of 500–1500 GeV. As was also done in the previous ATLAS publication [20], the value of the coupling parameter λ was set to 0.01 × 4 π α , where α is the fine-structure constant. This value of λ determines the leptoquark natural width, which is less than 100 MeV and is smaller than the detector resolution for the reconstruction of leptoquark mass. It also leads to a LQ lifetime sufficiently small such that LQs in the mass range considered in this work would decay promptly. Next-to-leading-order (NLO) calculations [9] of the cross sections for scalar leptoquark pair-production were used to normalise the signal samples.

The dominant SM backgrounds arise from processes which can produce a final state containing two reconstructed high transverse momentum (p_T) leptons (electrons or muons) and jets. Simulated samples were made of Drell–Yan production ( q q ¯ → Z / γ * → ℓ + ℓ − ) and the production of t t ¯ , diboson (WW, WZ, and ZZ) and single top-quarks in association with a W boson.

Drell–Yan events with associated jets were simulated using the Sherpa 2.1.1 [29] generator. Matrix elements were calculated for up to two partons at NLO and four partons at LO using the Comix [30] and OpenLoops [31] matrix-element generators and merged with the Sherpa parton shower [32] using the ME+PS@NLO prescription [33]. The CT10 PDF set [34] was used in conjunction with dedicated parton-shower tuning developed by the authors of Sherpa [32].

For the generation of t t ¯ and single top quarks in the Wt channel, the Powheg-Box v2 generator [35–38] with the CT10 PDF set in the matrix-element calculations was used. For both processes the parton shower, fragmentation, and the underlying event were simulated using Pythia 6.428 [39] with the Perugia 2012 tune [40] and using the Cteq6L1 PDF set [41]. The top-quark mass was set to 172.5 GeV. The EvtGen v1.2.0 program [42] was used to simulate the bottom and charm hadron decays.

Diboson processes with four charged leptons, three charged leptons + one neutrino or two charged leptons and two neutrinos were simulated using the Sherpa 2.1.1 generator. Matrix elements contain all diagrams with four electroweak vertices. They were calculated for up to one ( 4 ℓ , 2 ℓ + 2 ν ) or zero partons ( 3 ℓ + 1 ν ) at NLO and up to three partons at LO using the Comix and OpenLoops matrix element generators and merged with the Sherpa parton shower using the ME+PS@NLO prescription. Diboson processes with one of the bosons decaying hadronically and the other leptonically were simulated using the same Sherpa version.

All samples of simulated events include the effect of multiple proton–proton interactions in the same or neighbouring bunch crossings (pile-up) which were modelled by overlaying simulated minimum-bias events on each generated signal and background event. These multiple interactions were simulated with the soft QCD processes of Pythia 8.186 [26] using tune A2 [43] and the MSTW2008LO PDF set [44]. The number of overlaid events was chosen to match the average number of interactions per pp bunch crossing observed in the data as it evolved throughout the data-taking period (giving an average of 14 interactions per crossing for the whole data-taking period). The SM background samples were processed through the GEANT4-based detector simulation [45, 46], while a fast simulation using a parameterisation of the performance of the calorimeters [47] and GEANT4 for the other parts of the detector was used for the signal samples and some samples used for studies of systematic uncertainties. The standard ATLAS reconstruction software was used for both simulated and collision data.

Estimates of the cross sections of background processes were taken from the following theoretical predictions. Single-top production was calculated at NLO+next-to-next-to-leading-logarithm (NNLL) accuracy [48]. Estimates of Drell–Yan and t t ¯ production cross sections at NLO [29] and NLO+NNLO [49] accuracy, respectively, were used.

4.

The electron energy was measured using its associated cluster of electromagnetic-calorimeter cells with significant energy deposits, whereas the direction was determined by the track associated with this cluster. To identify and select electrons, requirements were placed on the shape of the cluster, on the quality of the associated track, and on the degree of matching between the track and cluster. Electron candidates must have transverse energy E T > 30 GeV and  ∣ η ∣ < 2.47 . Electron candidates associated with clusters in the transition region between the barrel and endcap calorimeters (1.37 < ∣ η ∣ < 1.52) were not considered. All electrons must be reconstructed with a cluster-based or a combined cluster- and track-based algorithm [50]. Furthermore, the impact parameters of the electron track relative to the beam line were required to satisfy ∣ d 0 / σ d 0 ∣ < 5 and ∣ z 0 sin θ ∣ < 0.5 mm , where d₀, σ d 0 and z₀ are the transverse impact parameter, its uncertainty, and the longitudinal impact parameter, respectively. In addition, electron isolation requirements were imposed on the summed transverse momentum of tracks (transverse energy of clusters) in a cone around the electron track (cluster barycentre). The radius of the cone around the track is Δ R = 10 GeV / p T for p T > 50 GeV and 0.2 otherwise^{226 226}

Here, Δ R = ( Δ η ) 2 + ( Δ ϕ ) 2 is a cone defined by differences in pseudorapidity and azimuthal angle. p T is given in GeV.

. For the cluster isolation, a fixed cone radius size of 0.2 is used. The efficiency of these isolation criteria is higher than 99%. The reconstruction efficiency is higher than 98% in most regions of transverse momentum and pseudorapidity. The identification efficiency varies between 75% and 92%, rising as a function of E T [51]. All of these efficiencies refer to the efficiency for a single electron, independent of the specific event topology.

Muon tracks were reconstructed independently in the ID and the MS. These muon tracks were required to have a minimum number of associated hits in each system and to satisfy geometrical and momentum matching criteria. The two tracks were then used as input to a combined fit which takes into account the energy loss in the calorimeter and multiple-scattering effects [52]. To improve momentum resolution and ensure a reliable measurement at very high momenta, muon tracks were required to have at least three hits in each of the three precision chambers in the MS. Tracks which traverse precision chambers with poor alignment were rejected. Finally, measurements of charge over momentum, performed independently in the ID and MS, were required to agree within seven standard deviations of the sum in quadrature of the uncertainties in the corresponding ID and MS measurements. Muon candidates were required to have p_T > 40 GeV and ∣ η ∣ < 2.5. Those falling in the overlap region of the MS barrel and endcap ( 1.01 < ∣ η ∣ < 1.10 ) were rejected due to the potential p_T mismeasurement resulting from relative barrel-endcap misalignment. Muon candidates were required to fulfil ∣ d 0 / σ d 0 ∣ < 3 and ∣ z 0 sin θ ∣ < 0.5 mm. In order to reduce the background from light- and heavy-hadron decays within jets, muons were required to fulfil isolation requirements. The track-based isolation variable used is the sum of the transverse momenta of the tracks in a cone around the muon of size Δ R = 10 GeV / p T μ , excluding the muon itself and with p T μ in GeV. The isolation efficiency is greater than 99%. The efficiency for reconstructing and identifying muons using the criteria described above is typically greater than 80% for the transverse momentum and pseudorapidity selections used in this work [53]. As for electrons, these efficiencies refer to single objects.

The anti-k_t algorithm [54] with a radius parameter R = 0.4 was used to reconstruct jets from energy clusters in the calorimeter [55]. Jet calibration is performed using energy- and η-dependent correction factors derived from simulations together with further corrections from in situ measurements. The jets used in this work must satisfy p_T > 50 GeV and ∣ η ∣ < 2.8. Further selections were applied to ensure that all jets considered are well measured [56]. A description of the jet energy scale (JES) measurement and its associated systematic uncertainties can be found in [57]. Jet-flavour tagging techniques were not used in this paper and, as a consequence, good sensitivity was maintained for LQ decays into a lepton plus any quark flavour barring the top quark.

Ambiguities in the object identification during reconstruction, i.e. when a reconstructed object matched multiple object identification hypotheses (electron, muon, jet), were resolved in the following way. First, electrons were removed if they shared their track with a muon. In a second step, ambiguities between electrons and jets were removed; if the two objects had Δ R < 0.2 the jet was rejected; if 0.2 < Δ R < 0.4 the electron was rejected. Finally, muon-jet ambiguities were resolved as follows: if the muon and jet were closer than Δ R = 0.4 the jet was rejected if it has less than three tracks, otherwise the muon was rejected. For the definition of signal and control regions (see section 6) only objects remaining after this procedure were considered.

5.

Proton–proton collision data at a centre-of-mass energy of s = 13 TeV, collected by the ATLAS detector at the LHC during 2015, were used. After applying data quality criteria, the dataset corresponds to an integrated luminosity of 3.2 fb⁻¹.

Events considered in the search were selected by the ATLAS two-level trigger system [58]. In the eejj channel, a two-electron trigger was used with an E T threshold of 17 GeV for each electron. The μ μ jj search used events selected by either of two single-muon triggers. The first trigger has a muon p T threshold of 26 GeV and additional requirements on its properties. In particular, it requires the muon to be isolated, which leads to a loss in efficiency at high p T . To retain a high trigger efficiency in the region of high p T , the second trigger, which has a p T threshold of 50 GeV but no additional requirements, was used. The trigger efficiencies for the eejj and μ μ jj searches exceed 90% for the object kinematics considered in this analysis.

Multiple pp interactions during bunch crossings lead to events containing a number of reconstructed vertices. The primary vertex of the event is defined as that vertex with the largest sum of squared transverse momenta of its associated tracks. Events which contain a primary vertex with at least two associated tracks satisfying p T , track > 0.4 GeV were selected. Furthermore, MC events were given a per-event weight to correct for differences in the distribution of the average number of pp interactions per bunch crossing between data and simulation.

Only events with exactly two charged leptons and at least two jets were considered for this analysis. Scale factors were applied as event weights to correct the MC description of lepton trigger, reconstruction, identification, isolation and impact-parameter cut efficiencies. A description of the derivation of the scale factors, obtained by comparing data and MC predictions in dedicated studies, can be found in [50, 59].

6.

The analysis presented here used signal (SR), control (CR) and validation (VR) regions to optimise signal significance and to constrain the normalisation of the main background sources. The latter are Drell–Yan events containing Z / γ * → e + e − , μ + μ − +jets processes (hereafter termed DY+jets) and t t ¯ events in which both top quarks decay leptonically. The signal, control and validation regions were defined using the following discriminating observables:

•

The dilepton invariant mass: m ℓ ℓ .

•

The scalar sum S T of the transverse momentum of the two leptons and of the two leading jets.

•

The minimum invariant mass of the two lepton–jet pairs in an event, m LQ min . The lepton–jet pairs were chosen such that the invariant mass difference between them was smallest. The lower mass of the two combinations was chosen as the discriminating variable following dedicated sensitivity studies.

The signal region was defined by requiring m ℓ ℓ > 130 GeV and S T  > 600 GeV. The cut on m ℓ ℓ was chosen to reduce the DY+jets background. The cut on S T was optimised by maximising the discovery significance [60] for LQs with masses between 500 and 1500 GeV, i.e. by performing a likelihood fit (described in more detail at the end of this section) using the m LQ min  distribution defined above for S T values between 0 and 3 TeV in steps of 100 GeV. This study showed that there is little dependence of the optimised S T value on the LQ mass when using the shape information of the mass spectrum. It was confirmed that the approach used in previous results, i.e. a cut-and-count analysis in several signal regions defined by varying cuts on the three variables mentioned above, does not give better sensitivity.

The signal selection efficiency is defined as the fraction of all simulated signal events, generated across the full phase space, that survive the trigger and the final SR selection. For leptoquarks of the first (second) generation, the overall selection efficiency rises from around 62% to 71% (38% to 43%) as the mass increases from 500 to 1500 GeV. The lower efficiency for second-generation leptoquarks is due to the muon track requirements, which demand hits in three MS stations, and which are needed to give an optimal momentum resolution at high p_T  for this analysis.

Three non-overlapping control regions with negligible signal contamination were defined. Differences in the predicted and observed event yields in these regions were used to evaluate scale factors which were used to normalise the MC predictions for the t t ¯ and DY+jets backgrounds in the SRs. The two DY+jets CRs — one for the eejj and one for the μ μ jj channel — were defined by requiring at least two jets and exactly two same-flavour leptons with a dilepton invariant mass restricted to a window around the Z boson mass: 70 < m ℓ ℓ < 110 GeV . The t t ¯ control region requires at least two jets, exactly one muon and exactly one electron: these events were selected with the same single-muon triggers as described in section 5. This control region is common to both channels.

Validation regions were used to verify that data and MC predictions agree in a phase space close to the signal regions, but still with a negligible signal contamination. This was achieved by applying the same selection as for the signal region, but inverting the cut on S T , i.e. allowing only values below 600 GeV. The requirements for the various regions are collected in table 1.

Table 1.

Definition of control, signal and validation regions. In all regions, at least two jets were required.

Region	Channel	#e	#μ	m ℓ ℓ (GeV)	S T (GeV)
t t ¯ CR	Both	1	1	—	—
DY+jets CR	eejj	2	0	[ 70 , 110 ]	—
	μ μ jj	0	2
SR	eejj	2	0	>130	>600
	μ μ jj	0	2
VR	eejj	2	0	>130	<600
	μ μ jj	0	2

For the statistical analysis, a profile-likelihood fit of signal plus background templates to the data was performed using the HistFitter package [61]. Systematic uncertainties, which are discussed in section 8, were incorporated into the likelihood as constrained nuisance parameters. The fit was performed in the CRs and the SR simultaneously and was used to extract normalisation factors, i.e. scaling corrections to the event yields predicted by theoretical cross-section calculations, described in section 3. In the CRs, only the event yield was used to extract the dominant background ( t t ¯ and DY+jets) normalisation factors. In the SR, both the normalisation and the shape of m LQ min distribution were used in the fit to extract the signal normalisation factor. The templates of the m LQ min shape consisted of ten bins: six bins of 100 GeV width from 0 to 600 GeV and four bins of 200 GeV width that cover the range up to 1.4 TeV. The template for the signal was derived from MC predictions. For the background templates, MC predictions as well as data-driven techniques were used, as detailed in the following section.

7.

Normalisation factors for the MC predictions of the two main SM backgrounds (DY+jets and t t ¯ ) were estimated with a fit to the data, as described in section 6. In total, four normalisation factors were calculated: one each for t t ¯ and DY+jets events in both the electron and muon channels.

Smaller background contributions arise from the production of a single top quark in the Wt channel, diboson events and Z → τ τ +jets events. These were estimated purely from simulation, i.e. their normalisation was not a free parameter in the combined fit.

Misidentified or non-prompt leptons originating from hadron decays or photon conversions can arise in multi-jet events, single top production in the s- or t-channel, W+jets and t t ¯ events (with at least one top quark decaying hadronically). This fake-lepton background is negligible in the μ μ jj  channel. In the eejj  channel it was evaluated using the same data-driven method as in [62]. This method was used to evaluate the migration of events among four different data samples: the nominal SR and three analogous samples selected with modified electron selection criteria. The migration between different regions can be described by a matrix, the elements of which are functions of the proportions of true and fake electrons. As a simplification of [62], the fake and real rates were evaluated as a function of p_T only, since they were observed to be independent of η within the required accuracy. They were considered to be the same for all electron candidates in an event. The fake background estimation suffers from low statistical precision. Its statistical uncertainty was treated as one source of the systematic uncertainty in the total background modelling.

Figure 3 shows the dilepton invariant mass for pairs of electrons (a) and muons (b) in events containing exactly two reconstructed same-flavour leptons and at least two reconstructed jets, following the selections given in section 5. This selection stage is also referred to as preselection. The predictions of various background sources are compared with the data. The hatched bands show the total systematic uncertainty in the background prediction. Within the uncertainties, agreement between data and simulation is observed. Normalisation factors for the MC predictions for DY+jets and t t ¯ events are not applied in the plot.

Figure 3.

Dilepton invariant mass for pairs of (a) electrons and (b) muons in events containing exactly two reconstructed same-flavour leptons and at least two reconstructed jets. Data are compared to the background prediction. The DY+jets and t t ¯ expectations are shown without the normalisation factors from the fit described in section 6. The hatched bands show the total systematic uncertainty in the background prediction.

Figure 4 shows the spectrum of the minimum reconstructed lepton–jet mass in the t t ¯ control region before the fit. Within uncertainties, the data and MC distributions are consistent.

Figure 4.

Minimum reconstructed lepton–jet invariant mass in the t t ¯ control region. Data are compared to the background prediction. The t t ¯ prediction is shown without the normalisation factor from the fit described in section 6. The hatched bands show the total systematic uncertainty in the background prediction.

8.

The following sources of systematic uncertainty were considered:

•

The uncertainty in the integrated luminosity is 5%. It was derived following a methodology similar to that detailed in [63], from a calibration of the luminosity scale using x–y beam-separation scans performed in August 2015. This uncertainty affects the predicted signal event yield and those background rates for which theoretical estimates are used.

•

The JES uncertainty depends on the p_T and η of the jet and on the pile-up conditions in an event. A further uncertainty in the jet energy resolution was taken into account. These sources each correspond to uncertainties in the jet energy of up to 3%. The largest resulting uncertainty in the background event yields is about 10% in the control regions. In the signal region, the uncertainty in the event yields amounts to at most 5% for the background and less than 1% for the signal.

•

The uncertainty in the lepton trigger efficiency scale factors is around 2% for the kinematic region considered here.

•

Differences between the MC and data in the efficiency of the isolation requirement on the selected muons correspond to uncertainties of 1%–5% on the scale factor to correct the MC prediction. Other muon-related uncertainties arise from the momentum scale, resolution, and quality criteria and typically affect the muon event yields by around 1% in all regions for both signal and background.

•

Uncertainties in the electron energy scale, identification and isolation affect the electron event yields by up to 2% in all regions for both signal and background.

•

Uncertainties due to choices that have to be made in the event generation which affect final-state observables were estimated for the two major background sources: t t ¯ and DY+jets. These modelling uncertainties refer to e.g. possible differences in the generation of the hard scattering, scale dependencies, the parton shower and hadronisation and fragmentation models. Differences in the background modelling can change the event yields (total normalisation) in the CRs. Moreover, there is an uncertainty in the shape of the m LQ min distribution in the signal region due to background modelling effects. This was estimated as one uncertainty per m LQ min -bin in the signal region and propagated to the normalisation factor by the fit. The uncertainties were treated as uncorrelated between different bins.

The impact of modelling uncertainties in final-state predictions for t t ¯ processes was quantified by comparing various simulated samples: differences due to the parton shower as well as the hadronisation and fragmentation model were estimated by comparing the nominal sample to one that uses Herwig++ [64], effects of additional or reduced radiation were estimated by varying the parton-shower and scale parameters within Pythia, and an alternative generator (aMC@NLO [65] with Herwig++) was used to estimate differences in the hard scatter generation. The total uncertainty in the predicted t t ¯ event yield varies between 14% (in the t t ¯ CR) to about 30% (in the signal regions).

Modelling uncertainties for the DY+jets background were assessed with different approaches, simulation-based, as well as data-driven in different regions of phase space. The baseline estimate used events from the DY+jets control region with S T higher than 600 GeV. In this region, the shapes of both the m LQ min and S T distributions are very similar to those in the signal region, which differs only by the cut on the dilepton invariant mass. This cut was found to not affect the shapes of the other discriminating variables. The difference between the data and the background prediction in this region was used as an estimate of the modelling uncertainty.

The result was cross-checked using simulated samples in which the renormalisation, factorisation and resummation scales, as well as the scale for matrix element and parton shower matching, were independently varied up and down by a factor of two. Within the statistical uncertainties resulting from the limited number of events in these samples, the estimate from the data-driven approach was confirmed. The result is a 10% uncertainty in the DY+jets event yield in the control regions and 20% in each m LQ min bin in the signal region.

•

PDF uncertainties on the t t ¯ and DY+jets normalisation as well as the m LQ min shape amount to less than 4% and do not affect the final result given the large modelling uncertainties described above.

•

The effects of higher-order contributions on the signal cross section were estimated by varying the QCD renormalisation and factorisation scales, set to a common value, up and down by a factor of two, as done in [9]. One half of the difference between the predicted cross section for the increased and reduced scale choice is used as the cross section uncertainty for a given mass. This uncertainty lies in the the range 12%–17% for the mass points considered in this paper.

•

The impact of theoretical uncertainties related to the parton-shower algorithm and multiple-interactions tune were evaluated by varying the corresponding parameters, as specified in [66]. This leads to an uncertainty in signal acceptance of up to 2%.

•

The uncertainty in the signal cross section due to the choice of PDF set was calculated as the envelope of the predictions of 40 different CTEQ6.6 NLO error sets [9]. The uncertainty ranges from 11% at m LQ  = 500 GeV to 34% at m LQ =1500 GeV. The predicted signal acceptance was studied using NNPDF23LO [28], CT14 [67] and MMHT14 [68] PDF sets. The acceptance is very insensitive to the choice of parton distribution function; the systematic uncertainty from this source is less than 1%.

9.

The results are consistent with SM expectations. The normalisation factors obtained in the fit described in section 6 are summarised in table 2. Similar results are obtained in the two channels and the normalisation factors are found to be compatible with unity within the uncertainties. The reliability of extrapolating the background predictions from the control regions to the signal region was checked in the VRs defined in section 6. The distribution of m LQ min in the two validation regions is compared to the background prediction after the fit in figure 5. Within the uncertainties, the predictions are compatible with the observed data.

Figure 5.

Minimum reconstructed lepton–jet invariant mass in the validation regions for pairs of (a) electrons and (b) muons. Data are compared to the background prediction. The DY+jets and t t ¯ expectations are scaled by the normalisation factors obtained from the fit described in section 6. The hatched bands show the total systematic uncertainty in the background prediction.

Table 2.

Normalisation factors for the main backgrounds obtained from the combined fit in each of the channels.

Channel	DY+jets	t t ¯
eejj	0.9 ± 0.1	1.0 ± 0.1
μ μ jj	0.9 ± 0.1	1.0 − 0.1 + 0.2

The observed and expected event yields in the signal regions for the eejj and the μ μ jj channels, after the fits, are shown in tables 3 and 4, respectively. The values in these tables are intended to illustrate the sensitivity independent of a specific signal hypothesis and thus, in this case, the fit was performed using only the control regions as input. The resulting fit parameters (DY+jets and t t ¯ normalisation factors and values of the nuisance parameters) were transferred to the signal region, using appropriate transfer factors based on the MC models. The different contributions to the background do not necessarily exactly sum to the total quoted number of background events owing to the rounding scheme used. The dominant experimental systematic uncertainties in the background prediction arise from uncertainties on corrections to the simulated electron and muon trigger efficiencies and the JES; the latter source gives an uncertainty of 2%–4% in the signal region. The luminosity uncertainty of 5% contributes for simulated backgrounds not constrained by the fit (diboson and single-top production). The theoretical uncertainties after the fit range from 3% to 12% for the DY+jets background and from 3% to 16% for the t t ¯ background. The global fit takes correlations of the nuisance parameters into account, which results in the uncertainty in the total background being smaller than the quadratic sum of the uncertainties in the separate components. The contribution of Z → τ τ + jets to the background is negligible and not shown in the tables.

Table 3.

Observed and predicted event yields in the signal and control regions in the eejj channel. The background prediction with its total uncertainty after the fit is shown. The fit is performed using only the control regions as input. The lower part of the table shows the separate contributions from the different background processes and their total uncertainty after the fit. In addition, the expected signal event yields for β = 1 and LQ masses of 500, 1000, and 1500 GeV are given.

	SR	CR DY+jets	CR t t ¯
Observed events	279	20328	5194
Total background events	300 ± 30	20300 ± 200	5200 ± 50
Fitted DY+jets events	74 ± 7	19100 ± 200	< 0.01
Fitted t t ¯ events	190 ± 30	1060 ± 10	4840 ± 40
MC predicted diboson events	12.5 ± 0.6	63 ± 3	115 ± 6
MC predicted single-top events	20 ± 1	42 ± 2	230 ± 10
Estimated fake-lepton events	9 ± 4	120 ± 10	6 ± 3
MC exp. signal events (mLQ = 500 GeV)	1000 ± 100	26 ± 4	< 0.01
MC exp. signal events (mLQ = 1000 GeV)	13 ± 2	0.03 ± 0.00	< 0.01
MC exp. signal events (mLQ = 1500 GeV)	0.6 ± 0.1	< 0.01	< 0.01

Table 4.

Observed and predicted event yields in the signal and control regions in the μ μ jj channel. The background prediction with its total uncertainty after the fit is shown. The fit is performed using only the control regions as input. The lower part of the table shows the separate contributions from the different background processes and their total uncertainty after the fit. Where no number is given, the contribution is found to be negligible. In addition, the expected signal event yields for β = 1 and LQ masses of 500, 1000, and 1500 GeV are given.

	SR	CR DY+jets	CR t t ¯
Observed events	188	10233	5194
Fitted background events	200 ± 30	10200 ± 100	5200 ± 70
Fitted DY+jets events	56 ± 8	9800 ± 100	9 ± 1
Fitted t t ¯ events	120 ± 30	400 ± 20	4840 ± 80
MC predicted diboson events	8.6 ± 0.6	32 ± 3	115 ± 10
MC predicted single-top events	12.8 ± 0.9	18 ± 2	230 ± 20
Estimated fake-lepton events	—	—	—
MC exp. signal events (mLQ = 500 GeV)	610 ± 40	25 ± 2	3 ± 3
MC exp. signal events (mLQ = 1000 GeV)	8.0 ± 0.8	0.08 ± 0.01	0.1 ± 0.1
MC exp. signal events (mLQ = 1500 GeV)	0.33 ± 0.06	< 0.01	< 0.01

Figure 6 shows the SR distribution of m LQ min compared to background predictions based on the combined fit in the CRs and the SR. The signal prediction for a LQ of mass 1.1 TeV is also shown. The wider signal shape in the muon channel compared to the electron channel is due the worsening of the muon momentum resolution with increasing momentum. Again, no significant deviation from the SM predictions was observed. Limits on the LQ signal strength were derived using pseudo-experiments and following a modified frequentist CL s method [69]. Apart from the luminosity uncertainty (5%), dominant uncertainties in the signal event yields arise from lepton scale factors and are of the order of 2%–5% at low masses and up to 10% at high masses.

Figure 6.

Distribution of the minimum reconstructed LQ candidate mass, m LQ min , in the signal region of (a) the first-generation leptoquark search and (b) the second-generation search. Data are compared to the background prediction. The DY+jets and t t ¯ expectations are scaled by the normalisation factors obtained from the fit described in section 6. The signal expectation for a LQ of mass 1.1 TeV is also shown. The hatched bands show the total systematic uncertainty in the background prediction.

In figure 7, limits on the cross section times branching ratio are shown on the left, for leptoquarks of the first (second) generation in the top (bottom) plot. The expected limit is depicted by the dashed line; the uncertainty bands result from considering all sources of systematic as well as statistical uncertainties. The observed limit is given by the solid line. The NLO pair-production cross section for β = 1 is shown as a line with a shaded band representing the uncertainties. The shaded band around it illustrates the uncertainties in the theoretical prediction due to PDF and scale uncertainties. The intersection of this line with the cross-section limits yields the lower limit on the leptoquark mass for a value of β = 1 . These observed (expected) limits are found to be 1100 (1160 GeV) and 1050 GeV (1040 GeV) for first- and second-generation LQs, respectively. The observed limit for each channel is stronger than the previous bound [20] by 50 GeV. The expected limits are improved by 110 GeV for the first-generation search and by 40 GeV in the second generation search. The theoretical cross section was scaled by β 2 and then used to obtain the limits on the branching ratio as a function of the LQ mass shown on the right of figure 7. Below LQ masses of 650 GeV, the limits on β are weaker than those obtained at 8 TeV centre-of-mass energy, which are shown as the dashed–dotted line, owing to the much lower integrated luminosity collected in 2015 and the effects of background at lower LQ masses. At high masses (above 900GeV), however, the gain in the production cross section at 13 TeV compensates for the smaller luminosity and stronger bounds than at 8 TeV are obtained. In the intermediate mass region, the results are comparable. Mass limits for various values of β are summarised in table 5.

Figure 7.

The cross-section limits (a) on scalar LQ pair production times the square of the branching ratio as a function of mass and (b) limits on the branching ratio as a function of mass for first-generation leptoquarks. Analogous limits are shown for second-generation leptoquarks in (c) and (d). Expected and observed limits are also shown. The uncertainty bands on the expected limit represent all sources of systematic and statistical uncertainty. On the left, the expected NLO production cross section (β = 1.0) for scalar leptoquark pair-production and its corresponding theoretical uncertainty due to the choice of PDF set and renormalisation/factorisation scale are also included. The observed limit from the 8 TeV analysis is also shown on plots (b) and (d) [20].

Table 5.

Expected and observed 95% CL lower limits on first- and second-generation leptoquark masses for different assumptions of β.

β	95% CL limit on
	m LQ 1 (GeV)		m LQ 2 (GeV)
	Expected	Observed	Expected	Observed
1.00	1160	1100	1040	1050
0.75	1050	1000	950	960
0.50	900	900	800	830
0.25	680	700	580	600

10.

Searches for first- and second-generation scalar leptoquarks, pair-produced in pp collisions at 13 TeV centre-of-mass energy, have been performed with the ATLAS detector at the LHC. An integrated luminosity of 3.2 fb⁻¹ of data was used. No significant excess above the SM background expectation was observed in either channel. The results were interpreted in the framework of the mBRW model. Mass-dependent limits were derived on the pair-production cross section times the square of the branching ratio ( β 2 ) and on β. For β = 1 , the observed (expected) LQ mass limits at 95% CL are 1100 and 1050 GeV (1160 and 1040 GeV) for first- and second-generation leptoquarks, respectively. The observed bounds are more stringent than the previous ATLAS limits by 50 GeV in each channel. This analysis is the first result at 13 TeV using the Run 2 data collected by the ATLAS experiment in a program of high precision inclusive searches for resonant signatures involving a lepton and a jet.

We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC, Hong Kong SAR, China; ISF, I-CORE and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA, Romania; MES of Russia and NRC KI, Russian Federation; JINR; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, the Canada Council, CANARIE, CRC, Compute Canada, FQRNT, and the Ontario Innovation Trust, Canada; EPLANET, ERC, FP7, Horizon 2020 and Marie Skłodowska-Curie Actions, European Union; Investissements d’Avenir Labex and Idex, ANR, Région Auvergne and Fondation Partager le Savoir, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF; BSF, GIF and Minerva, Israel; BRF, Norway; Generalitat de Catalunya, Generalitat Valenciana, Spain; the Royal Society and Leverhulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN and the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL (USA) and in the Tier-2 facilities worldwide.

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