Open Access

Observation of the decay $χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-}$

R. Aaij ³⁸, A. S. W. Abdelmotteleb ⁶⁴, C. Abellan Beteta ⁵⁸, F. Abudinén ⁶⁴, T. Ackernley ⁶⁸, A. A. Adefisoye ⁷⁶, B. Adeva ⁵⁴, M. Adinolfi ⁶², P. Adlarson ⁹⁶ et al. (LHCb Collaboration)

P. Adlarson ⁹⁶, C. Agapopoulou ¹⁴, C. A. Aidala ⁹⁸, Z. Ajaltouni¹¹, S. Akar ¹¹, K. Akiba ³⁸, M. Akthar ⁴⁰, P. Albicocco ²⁸, J. Albrecht ^19,a, R. Aleksiejunas ⁸⁸, F. Alessio ⁵⁶, P. Alvarez Cartelle ⁶³, R. Amalric ¹⁶, S. Amato ³, J. L. Amey ⁶², Y. Amhis ¹⁴, L. An ⁶, L. Anderlini ²⁷, M. Andersson ⁵⁸, P. Andreola ⁵⁸, M. Andreotti ²⁶, S. Andres Estrada ⁵¹, A. Anelli ^31,56,b, D. Ao ⁷, C. Arata ¹², F. Archilli ^37,c, Z. Areg ⁷⁶, M. Argenton ²⁶, S. Arguedas Cuendis ^9,56, L. Arnone ^31,b, A. Artamonov ⁵⁰, M. Artuso ⁷⁶, E. Aslanides ¹³, R. Ataíde Da Silva ⁵⁷, M. Atzeni ⁷², B. Audurier ¹², J. A. Authier ¹⁵, D. Bacher ⁷¹, I. Bachiller Perea ⁵⁷, S. Bachmann ²², M. Bachmayer ⁵⁷, J. J. Back ⁶⁴, P. Baladron Rodriguez ⁵⁴, V. Balagura ¹⁵, A. Balboni ²⁶, W. Baldini ²⁶, Z. Baldwin ⁸⁶, L. Balzani ¹⁹, H. Bao ⁷, J. Baptista de Souza Leite ², C. Barbero Pretel ^54,12, M. Barbetti ²⁷, I. R. Barbosa ⁷⁷, R. J. Barlow ⁷⁰, M. Barnyakov ²⁵, S. Barsuk ¹⁴, W. Barter ⁶⁶, J. Bartz ⁷⁶, S. Bashir ⁴⁰, B. Batsukh ⁵, P. B. Battista ¹⁴, A. Bay ⁵⁷, A. Beck ⁷², M. Becker ¹⁹, F. Bedeschi ³⁵, I. B. Bediaga ², N. A. Behling ¹⁹, S. Belin ⁵⁴, A. Bellavista ²⁵, K. Belous ⁵⁰, I. Belov ²⁹, I. Belyaev ³⁶, G. Benane ¹³, G. Bencivenni ²⁸, E. Ben-Haim ¹⁶, A. Berezhnoy ⁴⁶, R. Bernet ⁵⁸, S. Bernet Andres ⁵³, A. Bertolin ³³, F. Betti ⁶⁶, J. Bex ⁶³, O. Bezshyyko ⁹⁷, S. Bhattacharya ⁸⁷, J. Bhom ⁴¹, M. S. Bieker ¹⁸, N. V. Biesuz ²⁶, A. Biolchini ³⁸, M. Birch ⁶⁹, F. C. R. Bishop ¹⁰, A. Bitadze ⁷⁰, A. Bizzeti ^27,d, T. Blake ^64,e, F. Blanc ⁵⁷, J. E. Blank ¹⁹, S. Blusk ⁷⁶, V. Bocharnikov ⁹³, J. A. Boelhauve ¹⁹, O. Boente Garcia ⁵⁶, T. Boettcher ⁷⁵, A. Bohare ⁶⁶, A. Boldyrev ⁹³, C. Bolognani ⁹⁰, R. Bolzonella ^26,f, R. B. Bonacci ¹, N. Bondar ^44,56, A. Bordelius ⁵⁶, F. Borgato ^33,56, S. Borghi ⁷⁰, M. Borsato ^31,b, J. T. Borsuk ⁹¹, E. Bottalico ⁶⁸, S. A. Bouchiba ⁵⁷, M. Bovill ⁷¹, T. J. V. Bowcock ⁶⁸, A. Boyer ⁵⁶, C. Bozzi ²⁶, J. D. Brandenburg ⁹⁹, A. Brea Rodriguez ⁵⁷, N. Breer ¹⁹, J. Brodzicka ⁴¹, J. Brown ⁶⁸, D. Brundu ³², E. Buchanan ⁶⁶, M. Burgos Marcos ⁹⁰, A. T. Burke ⁷⁰, C. Burr ⁵⁶, C. Buti ²⁷, J. S. Butter ⁶³, J. Buytaert ⁵⁶, W. Byczynski ⁵⁶, S. Cadeddu ³², H. Cai ⁸², Y. Cai ⁵, A. Caillet ¹⁶, R. Calabrese ^26,f, S. Calderon Ramirez ⁹, L. Calefice ⁵², M. Calvi ^31,b, M. Calvo Gomez ⁵³, P. Camargo Magalhaes ^2,g, J. I. Cambon Bouzas ⁵⁴, P. Campana ²⁸, A. F. Campoverde Quezada ⁷, Y. Cao⁶, S. Capelli ³¹, M. Caporale ²⁵, L. Capriotti ²⁶, R. Caravaca-Mora ⁹, A. Carbone ^25,h, L. Carcedo Salgado ⁵⁴, R. Cardinale ^29,i, A. Cardini ³², P. Carniti ³¹, L. Carus ²², A. Casais Vidal ⁷², R. Caspary ²², G. Casse ⁶⁸, M. Cattaneo ⁵⁶, G. Cavallero ²⁶, V. Cavallini ^26,f, S. Celani ⁵⁶, I. Celestino ^35,j, S. Cesare ^30,k, A. J. Chadwick ⁶⁸, I. Chahrour ⁹⁸, H. Chang ^4,l, M. Charles ¹⁶, Ph. Charpentier ⁵⁶, E. Chatzianagnostou ³⁸, R. Cheaib ⁸⁷, M. Chefdeville ¹⁰, C. Chen ⁶³, J. Chen ⁵⁷, S. Chen ⁵, Z. Chen ⁷, A. Chen Hu ⁶⁹, M. Cherif ¹², A. Chernov ⁴¹, S. Chernyshenko ⁶⁰, X. Chiotopoulos ⁹⁰, V. Chobanova ⁵¹, M. Chrzaszcz ⁴¹, A. Chubykin ⁴⁴, V. Chulikov ^28,36,56, P. Ciambrone ²⁸, X. Cid Vidal ⁵⁴, G. Ciezarek ⁵⁶, P. Cifra ³⁸, P. E. L. Clarke ⁶⁶, M. Clemencic ⁵⁶, H. V. Cliff ⁶³, J. Closier ⁵⁶, C. Cocha Toapaxi ²², V. Coco ⁵⁶, J. Cogan ¹³, E. Cogneras ¹¹, L. Cojocariu ⁴³, S. Collaviti ⁵⁷, P. Collins ⁵⁶, T. Colombo ⁵⁶, M. Colonna ¹⁹, A. Comerma-Montells ⁵², L. Congedo ²⁴, J. Connaughton ⁶⁴, A. Contu ³², N. Cooke ⁶⁷, G. Cordova ^35,j, C. Coronel ⁷³, I. Corredoira ¹², A. Correia ¹⁶, G. Corti ⁵⁶, J. Cottee Meldrum ⁶², B. Couturier ⁵⁶, D. C. Craik ⁵⁸, M. Cruz Torres ^2,m, E. Curras Rivera ⁵⁷, R. Currie ⁶⁶, C. L. Da Silva ⁷⁵, S. Dadabaev ⁹⁴, X. Dai ⁴, E. Dall’Occo ⁵⁶, J. Dalseno ⁵¹, C. D’Ambrosio ⁶⁹, J. Daniel ¹¹, G. Darze ³, A. Davidson ⁶⁴, J. E. Davies ⁷⁰, O. De Aguiar Francisco ⁷⁰, C. De Angelis ^32,n, F. De Benedetti ⁵⁶, J. de Boer ³⁸, K. De Bruyn ⁸⁹, S. De Capua ⁷⁰, M. De Cian ^70,56, U. De Freitas Carneiro Da Graca ^2,o, E. De Lucia ²⁸, J. M. De Miranda ², L. De Paula ³, M. De Serio ^24,p, P. De Simone ²⁸, F. De Vellis ¹⁹, J. A. de Vries ⁹⁰, F. Debernardis ²⁴, D. Decamp ¹⁰, S. Dekkers ¹, L. Del Buono ¹⁶, B. Delaney ⁷², H.-P. Dembinski ¹⁹, J. Deng ⁸, V. Denysenko ⁵⁸, O. Deschamps ¹¹, F. Dettori ^32,n, B. Dey ⁸⁷, P. Di Nezza ²⁸, I. Diachkov ⁹⁴, S. Didenko ⁹⁴, S. Ding ⁷⁶, Y. Ding ⁵⁷, L. Dittmann ²², V. Dobishuk ⁶⁰, A. D. Docheva ⁶⁷, A. Doheny ⁶⁴, C. Dong ^4,l, A. M. Donohoe ²³, F. Dordei ³², A. C. dos Reis ², A. D. Dowling ⁷⁶, L. Dreyfus ¹³, W. Duan ⁸⁰, P. Duda ⁹¹, L. Dufour ⁵⁶, V. Duk ³⁴, P. Durante ⁵⁶, M. M. Duras ⁹¹, J. M. Durham ⁷⁵, O. D. Durmus ⁸⁷, A. Dziurda ⁴¹, A. Dzyuba ⁴⁴, S. Easo ⁶⁵, E. Eckstein ¹⁸, U. Egede ¹, A. Egorychev ⁴⁷, V. Egorychev ⁴⁷, S. Eisenhardt ⁶⁶, E. Ejopu ⁶⁸, L. Eklund ⁹⁶, M. Elashri ⁷³, D. Elizondo Blanco ⁹, J. Ellbracht ¹⁹, S. Ely ⁶⁹, A. Ene ⁴³, J. Eschle ⁷⁶, S. Esen ²², T. Evans ³⁸, F. Fabiano ³², S. Faghih ⁷³, L. N. Falcao ^31,b, B. Fang ⁷, R. Fantechi ³⁵, L. Fantini ^34,q, M. Faria ⁵⁷, K. Farmer ⁶⁶, F. Fassin ^89,38, D. Fazzini ^31,b, L. Felkowski ⁹¹, C. Feng⁶, M. Feng ^5,7, A. Fernandez Casani ⁵⁵, M. Fernandez Gomez ⁵⁴, A. D. Fernez ⁷⁴, F. Ferrari ^25,h, F. Ferreira Rodrigues ³, M. Ferrillo ⁵⁸, M. Ferro-Luzzi ⁵⁶, S. Filippov ⁴⁵, R. A. Fini ²⁴, M. Fiorini ^26,f, M. Firlej ⁴⁰, K. L. Fischer ⁷¹, D. S. Fitzgerald ⁹⁸, C. Fitzpatrick ⁷⁰, T. Fiutowski ⁴⁰, F. Fleuret ¹⁵, A. Fomin ⁵⁹, M. Fontana ²⁵, L. A. Foreman ⁷⁰, R. Forty ⁵⁶, D. Foulds-Holt ⁶⁶, V. Franco Lima ³, M. Franco Sevilla ⁷⁴, M. Frank ⁵⁶, E. Franzoso ^26,f, G. Frau ⁷⁰, C. Frei ⁵⁶, D. A. Friday ^70,56, J. Fu ⁷, Q. Führing ^19,63,a, T. Fulghesu ¹³, G. Galati ²⁴, M. D. Galati ³⁸, A. Gallas Torreira ⁵⁴, D. Galli ^25,h, S. Gambetta ⁶⁶, M. Gandelman ³, P. Gandini ³⁰, B. Ganie ⁷⁰, H. Gao ⁷, R. Gao ⁷¹, T. Q. Gao ⁶³, Y. Gao ⁸, Y. Gao ⁶, Y. Gao ⁸, L. M. Garcia Martin ⁵⁷, P. Garcia Moreno ⁵², J. García Pardiñas ⁷², P. Gardner ⁷⁴, L. Garrido ⁵², C. Gaspar ⁵⁶, A. Gavrikov ³³, L. L. Gerken ¹⁹, E. Gersabeck ²⁰, M. Gersabeck ²⁰, T. Gershon ⁶⁴, S. Ghizzo ^29,i, Z. Ghorbanimoghaddam ⁶², F. I. Giasemis ^16,r, V. Gibson ⁶³, H. K. Giemza ⁴², A. L. Gilman ⁷³, M. Giovannetti ²⁸, A. Gioventù ⁵², L. Girardey ^70,65, M. A. Giza ⁴¹, F. C. Glaser ^14,22, V. V. Gligorov ¹⁶, C. Göbel ⁷⁷, L. Golinka-Bezshyyko ⁹⁷, E. Golobardes ⁵³, D. Golubkov ⁴⁷, A. Golutvin ^69,56, S. Gomez Fernandez ⁵², W. Gomulka ⁴⁰, I. Gonçales Vaz⁵⁶, F. Goncalves Abrantes ⁷¹, M. Goncerz ⁴¹, G. Gong ^4,l, J. A. Gooding ¹⁹, I. V. Gorelov ⁴⁶, C. Gotti ³¹, E. Govorkova ⁷², J. P. Grabowski ³⁰, L. A. Granado Cardoso ⁵⁶, E. Graugés ⁵², E. Graverini ^57,s, L. Grazette ⁶⁴, G. Graziani ²⁷, A. T. Grecu ⁴³, N. A. Grieser ⁷³, L. Grillo ⁶⁷, S. Gromov ⁹⁴, C. Gu ¹⁵, M. Guarise ²⁶, L. Guerry ¹¹, A.-K. Guseinov ⁵⁷, E. Gushchin ⁴⁵, Y. Guz ^6,56, T. Gys ⁵⁶, K. Habermann ¹⁸, T. Hadavizadeh ¹, C. Hadjivasiliou ⁷⁴, G. Haefeli ⁵⁷, C. Haen ⁵⁶, S. Haken ⁶³, G. Hallett ⁶⁴, P. M. Hamilton ⁷⁴, J. Hammerich ⁶⁸, Q. Han ³³, X. Han ^22,56, S. Hansmann-Menzemer ²², L. Hao ⁷, N. Harnew ⁷¹, T. H. Harris ¹, M. Hartmann ¹⁴, S. Hashmi ⁴⁰, J. He ^7,t, A. Hedes ⁷⁰, F. Hemmer ⁵⁶, C. Henderson ⁷³, R. Henderson ¹⁴, R. D. L. Henderson ¹, A. M. Hennequin ⁵⁶, K. Hennessy ⁶⁸, L. Henry ⁵⁷, J. Herd ⁶⁹, P. Herrero Gascon ²², J. Heuel ¹⁷, A. Heyn ¹³, A. Hicheur ³, G. Hijano Mendizabal ⁵⁸, J. Horswill ⁷⁰, R. Hou ⁸, Y. Hou ¹¹, D. C. Houston ⁶⁷, N. Howarth ⁶⁸, W. Hu ⁷, X. Hu ⁴, W. Hulsbergen ³⁸, R. J. Hunter ⁶⁴, M. Hushchyn ⁹³, D. Hutchcroft ⁶⁸, M. Idzik ⁴⁰, D. Ilin ⁴⁴, P. Ilten ⁷³, A. Iniukhin ⁹³, A. Iohner ¹⁰, A. Ishteev ⁹⁴, K. Ivshin ⁴⁴, H. Jage ¹⁷, S. J. Jaimes Elles ^84,55,56, S. Jakobsen ⁵⁶, T. Jakoubek ⁸⁵, E. Jans ³⁸, B. K. Jashal ⁵⁵, A. Jawahery ⁷⁴, C. Jayaweera ⁶¹, V. Jevtic ¹⁹, Z. Jia ¹⁶, E. Jiang ⁷⁴, X. Jiang ^5,7, Y. Jiang ⁷, Y. J. Jiang ⁶, E. Jimenez Moya ⁹, N. Jindal ⁹⁹, M. John ⁷¹, A. John Rubesh Rajan ²³, D. Johnson ⁶¹, C. R. Jones ⁶³, S. Joshi ⁴², B. Jost ⁵⁶, J. Juan Castella ⁶³, N. Jurik ⁵⁶, I. Juszczak ⁴¹, K. Kalecinska⁴⁰, D. Kaminaris ⁵⁷, S. Kandybei ⁵⁹, M. Kane ⁶⁶, Y. Kang ^4,l, C. Kar ¹¹, M. Karacson ⁵⁶, A. Kauniskangas ⁵⁷, J. W. Kautz ⁷³, M. K. Kazanecki ⁴¹, F. Keizer ⁵⁶, M. Kenzie ⁶³, T. Ketel ³⁸, B. Khanji ⁷⁶, A. Kharisova ⁹⁵, S. Kholodenko ^69,56, G. Khreich ¹⁴, T. Kirn ¹⁷, V. S. Kirsebom ^31,b, O. Kitouni ⁷², S. Klaver ³⁹, N. Kleijne ^35,j, D. K. Klekots ⁹⁷, K. Klimaszewski ⁴², M. R. Kmiec ⁴², T. Knospe ¹⁹, R. Kolb ²², S. Koliiev ⁶⁰, L. Kolk ¹⁹, A. Konoplyannikov ⁶, P. Kopciewicz ⁵⁶, P. Koppenburg ³⁸, A. Korchin ⁵⁹, M. Korolev ⁴⁶, I. Kostiuk ³⁸, O. Kot ⁶⁰, S. Kotriakhova ³², E. Kowalczyk ⁷⁴, A. Kozachuk ⁴⁶, P. Kravchenko ⁴⁴, L. Kravchuk ⁴⁵, O. Kravcov ⁸⁸, M. Kreps ⁶⁴, P. Krokovny ^49,u, W. Krupa ⁷⁶, W. Krzemien ⁴², O. Kshyvanskyi ⁶⁰, S. Kubis ⁹¹, M. Kucharczyk ⁴¹, V. Kudryavtsev ^49,u, E. Kulikova ⁴⁸, A. Kupsc ⁹⁶, V. Kushnir ⁵⁹, B. Kutsenko ¹³, J. Kvapil ⁷⁵, I. Kyryllin ⁵⁹, D. Lacarrere ⁵⁶, P. Laguarta Gonzalez ⁵², A. Lai ³², A. Lampis ³², D. Lancierini ⁶⁹, C. Landesa Gomez ⁵⁴, J. J. Lane ¹, G. Lanfranchi ²⁸, C. Langenbruch ²², J. Langer ¹⁹, T. Latham ⁶⁴, F. Lazzari ^35,56,s, C. Lazzeroni ⁶¹, R. Le Gac ¹³, H. Lee ⁶⁸, R. Lefèvre ¹¹, A. Leflat ⁴⁶, S. Legotin ⁹⁴, M. Lehuraux ⁶⁴, E. Lemos Cid ⁵⁶, O. Leroy ¹³, T. Lesiak ⁴¹, E. D. Lesser ⁵⁶, B. Leverington ²², A. Li ^4,l, C. Li ^4,l, C. Li ¹³, H. Li ⁸⁰, J. Li ⁸, K. Li ⁸³, L. Li ⁷⁰, M. Li ⁸, P. Li ⁷, P.-R. Li ⁸¹, Q. Li ^5,7, T. Li ⁷⁹, T. Li ⁸⁰, Y. Li ⁸, Y. Li ⁵, Y. Li ⁴, Z. Lian ^4,l, Q. Liang⁸, X. Liang ⁷⁶, Z. Liang ³², S. Libralon ⁵⁵, A. Lightbody ¹², C. Lin ⁷, T. Lin ⁶⁵, R. Lindner ⁵⁶, H. Linton ⁶⁹, R. Litvinov ³², D. Liu ⁸, F. L. Liu ¹, G. Liu ⁸⁰, K. Liu ⁸¹, S. Liu ⁵, W. Liu ⁸, Y. Liu ⁶⁶, Y. Liu ⁸¹, Y. L. Liu ⁶⁹, G. Loachamin Ordonez ⁷⁷, I. Lobo ¹, A. Lobo Salvia ⁵², A. Loi ³², T. Long ⁶³, F. C. L. Lopes ^2,g, J. H. Lopes ³, A. Lopez Huertas ⁵², C. Lopez Iribarnegaray ⁵⁴, S. López Soliño ⁵⁴, Q. Lu ¹⁵, C. Lucarelli ⁵⁶, D. Lucchesi ^33,v, M. Lucio Martinez ⁵⁵, Y. Luo ⁶, A. Lupato ^33,w, E. Luppi ^26,f, K. Lynch ²³, S. Lyu⁶, X.-R. Lyu ⁷, G. M. Ma ^4,l, H. Ma ⁷⁹, S. Maccolini ¹⁹, F. Machefert ¹⁴, F. Maciuc ⁴³, B. Mack ⁷⁶, I. Mackay ⁷¹, L. M. Mackey ⁷⁶, L. R. Madhan Mohan ⁶³, M. J. Madurai ⁶¹, D. Magdalinski ³⁸, D. Maisuzenko ⁴⁴, J. J. Malczewski ⁴¹, S. Malde ⁷¹, L. Malentacca ⁵⁶, A. Malinin ⁹², T. Maltsev ⁴⁹, G. Manca ^32,n, G. Mancinelli ¹³, C. Mancuso ¹⁴, R. Manera Escalero ⁵², F. M. Manganella ³⁷, D. Manuzzi ²⁵, D. Marangotto ^30,k, J. F. Marchand ¹⁰, R. Marchevski ⁵⁷, U. Marconi ²⁵, E. Mariani ¹⁶, S. Mariani ⁵⁶, C. Marin Benito ⁵², J. Marks ²², A. M. Marshall ⁶², L. Martel ⁷¹, G. Martelli ³⁴, G. Martellotti ³⁶, L. Martinazzoli ⁵⁶, M. Martinelli ^31,b, D. Martinez Gomez ⁸⁹, D. Martinez Santos ⁵¹, F. Martinez Vidal ⁵⁵, A. Martorell i Granollers ⁵³, A. Massafferri ², R. Matev ⁵⁶, A. Mathad ⁵⁶, V. Matiunin ⁴⁷, C. Matteuzzi ⁷⁶, K. R. Mattioli ¹⁵, A. Mauri ⁶⁹, E. Maurice ¹⁵, J. Mauricio ⁵², P. Mayencourt ⁵⁷, J. Mazorra de Cos ⁵⁵, M. Mazurek ⁴², M. McCann ⁶⁹, N. T. McHugh ⁶⁷, A. McNab ⁷⁰, R. McNulty ²³, B. Meadows ⁷³, G. Meier ¹⁹, D. Melnychuk ⁴², D. Mendoza Granada ¹⁶, P. Menendez Valdes Perez ⁵⁴, F. M. Meng ^4,l, M. Merk ^38,90, A. Merli ^57,30, L. Meyer Garcia ⁷⁴, D. Miao ^5,7, H. Miao ⁷, M. Mikhasenko ⁸⁶, D. A. Milanes ^84,x, A. Minotti ^31,b, E. Minucci ²⁸, T. Miralles ¹¹, B. Mitreska ⁷⁰, D. S. Mitzel ¹⁹, R. Mocanu ⁴³, A. Modak ⁶⁵, L. Moeser ¹⁹, R. D. Moise ¹⁷, E. F. Molina Cardenas ⁹⁸, T. Mombächer ⁷³, M. Monk ⁶³, S. Monteil ¹¹, A. Morcillo Gomez ⁵⁴, G. Morello ²⁸, M. J. Morello ^35,j, M. P. Morgenthaler ²², A. Moro ^31,b, J. Moron ⁴⁰, W. Morren ³⁸, A. B. Morris ⁵⁶, A. G. Morris ¹³, R. Mountain ⁷⁶, Z. Mu ⁶, E. Muhammad ⁶⁴, F. Muheim ⁶⁶, M. Mulder ⁸⁹, K. Müller ⁵⁸, F. Muñoz-Rojas ⁹, R. Murta ⁶⁹, V. Mytrochenko ⁵⁹, P. Naik ⁶⁸, T. Nakada ⁵⁷, R. Nandakumar ⁶⁵, T. Nanut ⁵⁶, I. Nasteva ³, M. Needham ⁶⁶, E. Nekrasova ⁴⁷, N. Neri ^30,k, S. Neubert ¹⁸, N. Neufeld ⁵⁶, P. Neustroev⁴⁴, J. Nicolini ⁵⁶, D. Nicotra ⁹⁰, E. M. Niel ¹⁵, N. Nikitin ⁴⁶, L. Nisi ¹⁹, Q. Niu ⁸¹, P. Nogarolli ³, P. Nogga ¹⁸, C. Normand ⁶², J. Novoa Fernandez ⁵⁴, G. Nowak ⁷³, C. Nunez ⁹⁸, H. N. Nur ⁶⁷, A. Oblakowska-Mucha ⁴⁰, V. Obraztsov ⁵⁰, T. Oeser ¹⁷, A. Okhotnikov⁵⁰, O. Okhrimenko ⁶⁰, R. Oldeman ^32,n, F. Oliva ^66,56, E. Olivart Pino ⁵², M. Olocco ¹⁹, R. H. O’Neil ⁵⁶, J. S. Ordonez Soto ¹¹, D. Osthues ¹⁹, J. M. Otalora Goicochea ³, P. Owen ⁵⁸, A. Oyanguren ⁵⁵, O. Ozcelik ⁵⁶, F. Paciolla ^35,y, A. Padee ⁴², K. O. Padeken ¹⁸, B. Pagare ⁵⁴, T. Pajero ⁵⁶, A. Palano ²⁴, L. Palini ³⁰, M. Palutan ²⁸, C. Pan ⁸², X. Pan ^4,l, S. Panebianco ¹², S. Paniskaki ^56,33, G. Panshin ⁵, L. Paolucci ⁷⁰, A. Papanestis ⁶⁵, M. Pappagallo ^24,p, L. L. Pappalardo ²⁶, C. Pappenheimer ⁷³, C. Parkes ⁷⁰, D. Parmar ⁸⁶, G. Passaleva ²⁷, D. Passaro ^35,56,j, A. Pastore ²⁴, M. Patel ⁶⁹, J. Patoc ⁷¹, C. Patrignani ^25,h, A. Paul ⁷⁶, C. J. Pawley ⁹⁰, A. Pellegrino ³⁸, J. Peng ^5,7, X. Peng⁸¹, M. Pepe Altarelli ²⁸, S. Perazzini ²⁵, D. Pereima ⁴⁷, H. Pereira Da Costa ⁷⁵, M. Pereira Martinez ⁵⁴, A. Pereiro Castro ⁵⁴, C. Perez ⁵³, P. Perret ¹¹, A. Perrevoort ⁸⁹, A. Perro ^56,13, M. J. Peters ⁷³, K. Petridis ⁶², A. Petrolini ^29,i, S. Pezzulo ^29,i, J. P. Pfaller ⁷³, H. Pham ⁷⁶, L. Pica ^35,j, M. Piccini ³⁴, L. Piccolo ³², B. Pietrzyk ¹⁰, G. Pietrzyk ¹⁴, R. N. Pilato ⁶⁸, D. Pinci ³⁶, F. Pisani ⁵⁶, M. Pizzichemi ^31,56,b, V. M. Placinta ⁴³, M. Plo Casasus ⁵⁴, T. Poeschl ⁵⁶, F. Polci ¹⁶, M. Poli Lener ²⁸, A. Poluektov ¹³, N. Polukhina ⁹⁴, I. Polyakov ⁷⁰, E. Polycarpo ³, S. Ponce ⁵⁶, D. Popov ^7,56, K. Popp ¹⁹, S. Poslavskii ⁵⁰, K. Prasanth ⁶⁶, C. Prouve ⁵¹, D. Provenzano ^32,56,n, V. Pugatch ⁶⁰, A. Puicercus Gomez ⁵⁶, G. Punzi ^35,s, J. R. Pybus ⁷⁵, Q. Qian ⁶, W. Qian ⁷, N. Qin ^4,l, R. Quagliani ⁵⁶, R. I. Rabadan Trejo ⁶⁴, R. Racz ⁸⁸, J. H. Rademacker ⁶², M. Rama ³⁵, M. Ramírez García ⁹⁸, V. Ramos De Oliveira ⁷⁷, M. Ramos Pernas ⁶⁴, M. S. Rangel ³, F. Ratnikov ^48,93, G. Raven ³⁹, M. Rebollo De Miguel ⁵⁵, F. Redi ^30,w, J. Reich ⁶², F. Reiss ²⁰, Z. Ren ⁷, P. K. Resmi ⁷¹, M. Ribalda Galvez ⁵², R. Ribatti ⁵⁷, G. Ricart ^15,12, D. Riccardi ^35,j, S. Ricciardi ⁶⁵, K. Richardson ⁷², M. Richardson-Slipper ⁶³, F. Riehn ¹⁹, K. Rinnert ⁶⁸, P. Robbe ^14,56, G. Robertson ⁶⁷, E. Rodrigues ⁶⁸, A. Rodriguez Alvarez ⁵², E. Rodriguez Fernandez ⁵⁴, J. A. Rodriguez Lopez ⁸⁴, E. Rodriguez Rodriguez ⁵⁶, J. Roensch ¹⁹, A. Rogachev ⁹³, A. Rogovskiy ⁶⁵, D. L. Rolf ¹⁹, P. Roloff ⁵⁶, V. Romanovskiy ⁷³, A. Romero Vidal ⁵⁴, G. Romolini ^26,56, F. Ronchetti ⁵⁷, T. Rong ⁶, M. Rotondo ²⁸, S. R. Roy ²², M. S. Rudolph ⁷⁶, M. Ruiz Diaz ²², R. A. Ruiz Fernandez ⁵⁴, J. Ruiz Vidal ⁹⁰, J. J. Saavedra-Arias ⁹, J. J. Saborido Silva ⁵⁴, S. E. R. Sacha Emile R.⁵⁶, N. Sagidova ⁴⁴, D. Sahoo ⁸⁷, N. Sahoo ⁶¹, B. Saitta ³², M. Salomoni ^31,56,b, I. Sanderswood ⁵⁵, R. Santacesaria ³⁶, C. Santamarina Rios ⁵⁴, M. Santimaria ²⁸, L. Santoro ², E. Santovetti ³⁷, A. Saputi ^26,56, D. Saranin ⁹⁴, A. Sarnatskiy ⁸⁹, G. Sarpis ⁵⁶, M. Sarpis ⁸⁸, C. Satriano ³⁶, A. Satta ³⁷, M. Saur ⁸¹, D. Savrina ^46,47, H. Sazak ¹⁷, F. Sborzacchi ^56,28, A. Scarabotto ¹⁹, S. Schael ¹⁷, S. Scherl ⁶⁸, M. Schiller ²², H. Schindler ⁵⁶, M. Schmelling ²¹, B. Schmidt ⁵⁶, N. Schmidt ⁷⁵, S. Schmitt ⁷², H. Schmitz¹⁸, O. Schneider ⁵⁷, A. Schopper ⁶⁹, N. Schulte ¹⁹, M. H. Schune ¹⁴, G. Schwering ¹⁷, B. Sciascia ²⁸, A. Sciuccati ⁵⁶, G. Scriven ⁹⁰, I. Segal ⁸⁶, S. Sellam ⁵⁴, A. Semennikov ⁴⁷, T. Senger ⁵⁸, M. Senghi Soares ³⁹, A. Sergi ^29,i, N. Serra ⁵⁸, L. Sestini ²⁷, A. Seuthe ¹⁹, B. Sevilla Sanjuan ⁵³, Y. Shang ⁶, D. M. Shangase ⁹⁸, M. Shapkin ⁵⁰, R. S. Sharma ⁷⁶, I. Shchemerov ⁹⁴, L. Shchutska ⁵⁷, T. Shears ⁶⁸, L. Shekhtman ^49,u, J. Shen⁶, Z. Shen ³⁸, S. Sheng ^5,7, V. Shevchenko ⁹², B. Shi ⁷, Q. Shi ⁷, W. S. Shi ⁸⁰, Y. Shimizu ¹⁴, E. Shmanin ²⁵, R. Shorkin ⁹⁴, J. D. Shupperd ⁷⁶, R. Silva Coutinho ², G. Simi ^33,v, S. Simone ^24,p, M. Singha ⁸⁷, N. Skidmore ⁶⁴, T. Skwarnicki ⁷⁶, M. W. Slater ⁶¹, E. Smith ⁷², K. Smith ⁷⁵, M. Smith ⁶⁹, L. Soares Lavra ⁶⁶, M. D. Sokoloff ⁷³, F. J. P. Soler ⁶⁷, A. Solomin ⁶², A. Solovev ⁴⁴, K. Solovieva ²⁰, N. S. Sommerfeld ¹⁸, R. Song ¹, Y. Song ⁵⁷, Y. Song ^4,l, Y. S. Song ⁶, F. L. Souza De Almeida ⁵², B. Souza De Paula ³, K. M. Sowa ⁴⁰, E. Spadaro Norella ^29,i, E. Spedicato ²⁵, J. G. Speer ¹⁹, P. Spradlin ⁶⁷, F. Stagni ⁵⁶, M. Stahl ⁸⁶, S. Stahl ⁵⁶, S. Stanislaus ⁷¹, M. Stefaniak ⁹⁹, E. N. Stein ⁵⁶, O. Steinkamp ⁵⁸, D. Strekalina ⁹⁴, Y. Su ⁷, F. Suljik ⁷¹, J. Sun ³², J. Sun ⁷⁰, L. Sun ⁸², D. Sundfeld ², W. Sutcliffe ⁵⁸, P. Svihra ⁸⁵, V. Svintozelskyi ⁵⁵, K. Swientek ⁴⁰, F. Swystun ⁶³, A. Szabelski ⁴², T. Szumlak ⁴⁰, Y. Tan ⁴, Y. Tang ⁸², Y. T. Tang ⁷, M. D. Tat ²², J. A. Teijeiro Jimenez ⁵⁴, A. Terentev ⁹⁴, F. Terzuoli ^35,y, F. Teubert ⁵⁶, E. Thomas ⁵⁶, D. J. D. Thompson ⁶¹, A. R. Thomson-Strong ⁶⁶, H. Tilquin ⁶⁹, V. Tisserand ¹¹, S. T’Jampens ¹⁰, M. Tobin ^5,56, T. T. Todorov ²⁰, L. Tomassetti ^26,f, G. Tonani ³⁰, X. Tong ⁶, T. Tork ³⁰, D. Torres Machado ², L. Toscano ¹⁹, D. Y. Tou ^4,l, C. Trippl ⁵³, G. Tuci ²², N. Tuning ³⁸, L. H. Uecker ²², A. Ukleja ⁴⁰, D. J. Unverzagt ²², A. Upadhyay ⁵⁶, B. Urbach ⁶⁶, A. Usachov ³⁸, A. Ustyuzhanin ⁴⁸, U. Uwer ²², V. Vagnoni ^25,56, V. Valcarce Cadenas ⁵⁴, G. Valenti ²⁵, N. Valls Canudas ⁵⁶, J. van Eldik ⁵⁶, H. Van Hecke ⁷⁵, E. van Herwijnen ⁶⁹, C. B. Van Hulse ^54,z, R. Van Laak ⁵⁷, M. van Veghel ⁹⁰, G. Vasquez ⁵⁸, R. Vazquez Gomez ⁵², P. Vazquez Regueiro ⁵⁴, C. Vázquez Sierra ⁵¹, S. Vecchi ²⁶, J. Velilla Serna ⁵⁵, J. J. Velthuis ⁶², M. Veltri ^27,aa, A. Venkateswaran ⁵⁷, M. Verdoglia ³², M. Vesterinen ⁶⁴, W. Vetens ⁷⁶, D. Vico Benet ⁷¹, P. Vidrier Villalba ⁵², M. Vieites Diaz ⁵⁴, X. Vilasis-Cardona ⁵³, E. Vilella Figueras ⁶⁸, A. Villa ²⁵, P. Vincent ¹⁶, B. Vivacqua ³, F. C. Volle ⁶¹, D. vom Bruch ¹³, N. Voropaev ⁴⁴, K. Vos ⁹⁰, C. Vrahas ⁶⁶, J. Wagner ¹⁹, J. Walsh ³⁵, E. J. Walton ^1,64, G. Wan ⁶, A. Wang ⁷, B. Wang ⁵, C. Wang ²², G. Wang ⁸, H. Wang ⁸¹, J. Wang ⁷, J. Wang ⁵, J. Wang ^4,l, J. Wang ⁸², M. Wang ⁵⁶, N. W. Wang ⁷, R. Wang ⁶², X. Wang ⁸, X. Wang ⁸⁰, X. W. Wang ⁶⁹, Y. Wang ⁸³, Y. Wang ⁶, Y. H. Wang ⁸¹, Z. Wang ¹⁴, Z. Wang ³⁰, J. A. Ward ^64,1, M. Waterlaat ⁵⁶, N. K. Watson ⁶¹, D. Websdale ⁶⁹, Y. Wei ⁶, Z. Weida ⁷, J. Wendel ⁵¹, B. D. C. Westhenry ⁶², C. White ⁶³, M. Whitehead ⁶⁷, E. Whiter ⁶¹, A. R. Wiederhold ⁷⁰, D. Wiedner ¹⁹, M. A. Wiegertjes ³⁸, C. Wild ⁷¹, G. Wilkinson ^71,56, M. K. Wilkinson ⁷³, M. Williams ⁷², M. J. Williams ⁵⁶, M. R. J. Williams ⁶⁶, R. Williams ⁶³, S. Williams ⁶², Z. Williams ⁶², F. F. Wilson ⁶⁵, M. Winn ¹², W. Wislicki ⁴², M. Witek ⁴¹, L. Witola ¹⁹, T. Wolf ²², E. Wood ⁶³, G. Wormser ¹⁴, S. A. Wotton ⁶³, H. Wu ⁷⁶, J. Wu ⁸, X. Wu ⁸², Y. Wu ^6,63, Z. Wu ⁷, K. Wyllie ⁵⁶, S. Xian ⁸⁰, Z. Xiang ⁵, Y. Xie ⁸, T. X. Xing ³⁰, A. Xu ^35,j, L. Xu ^4,l, M. Xu ⁵⁶, Z. Xu ⁵⁶, Z. Xu ⁷, Z. Xu ⁵, S. Yadav ²⁶, K. Yang ⁶⁹, X. Yang ⁶, Y. Yang ⁷, Y. Yang ⁸⁷, Z. Yang ⁶, V. Yeroshenko ¹⁴, H. Yeung ⁷⁰, H. Yin ⁸, X. Yin ⁷, C. Y. Yu ⁶, J. Yu ⁷⁹, X. Yuan ⁵, Y Yuan ^5,7, J. A. Zamora Saa ⁷⁸, M. Zavertyaev ²¹, M. Zdybal ⁴¹, F. Zenesini ²⁵, C. Zeng ^5,7, M. Zeng ^4,l, C. Zhang ⁶, D. Zhang ⁸, J. Zhang ⁷, L. Zhang ^4,l, R. Zhang ⁸, S. Zhang ⁷¹, S. L. Zhang ⁷⁹, Y. Zhang ⁶, Y. Z. Zhang ^4,l, Z. Zhang ^4,l, Y. Zhao ²², A. Zhelezov ²², S. Z. Zheng ⁶, X. Z. Zheng ^4,l, Y. Zheng ⁷, T. Zhou ⁶, X. Zhou ⁸, Y. Zhou ⁷, V. Zhovkovska ⁶⁴, L. Z. Zhu ⁷, X. Zhu ^4,l, X. Zhu ⁸, Y. Zhu ¹⁷, V. Zhukov ¹⁷, J. Zhuo ⁵⁵, Q. Zou ^5,7, D. Zuliani ^33,v, and G. Zunica ²⁸ (LHCb Collaboration)

¹School of Physics and Astronomy, Monash University, Melbourne, Australia
²Centro Brasileiro de Pesquisas Físicas (CBPF), Rio de Janeiro, Brazil
³Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
⁴Department of Engineering Physics, Tsinghua University, Beijing, China
⁵Institute Of High Energy Physics (IHEP), Beijing, China
⁶School of Physics State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China
⁷University of Chinese Academy of Sciences, Beijing, China
⁸Institute of Particle Physics, Central China Normal University, Wuhan, Hubei, China
⁹Consejo Nacional de Rectores (CONARE), San Jose, Costa Rica
¹⁰Université Savoie Mont Blanc, CNRS, IN2P3-LAPP, Annecy, France
¹¹Université Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand, France
¹²Université Paris-Saclay, Centre d’Etudes de Saclay (CEA), IRFU, Gif-Sur-Yvette, France
¹³Aix Marseille Univ, CNRS/IN2P3, CPPM, Marseille, France
¹⁴Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
¹⁵Laboratoire Leprince-Ringuet, CNRS/IN2P3, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
¹⁶Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Sorbonne Université, CNRS/IN2P3, Paris, France
¹⁷I. Physikalisches Institut, RWTH Aachen University, Aachen, Germany
¹⁸Universität Bonn—Helmholtz-Institut für Strahlen und Kernphysik, Bonn, Germany
¹⁹Fakultät Physik, Technische Universität Dortmund, Dortmund, Germany
²⁰Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
²¹Max-Planck-Institut für Kernphysik (MPIK), Heidelberg, Germany
²²Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
²³School of Physics, University College Dublin, Dublin, Ireland
²⁴INFN Sezione di Bari, Bari, Italy
²⁵INFN Sezione di Bologna, Bologna, Italy
²⁶INFN Sezione di Ferrara, Ferrara, Italy
²⁷INFN Sezione di Firenze, Firenze, Italy
²⁸INFN Laboratori Nazionali di Frascati, Frascati, Italy
²⁹INFN Sezione di Genova, Genova, Italy
³⁰INFN Sezione di Milano, Milano, Italy
³¹INFN Sezione di Milano-Bicocca, Milano, Italy
³²INFN Sezione di Cagliari, Monserrato, Italy
³³INFN Sezione di Padova, Padova, Italy
³⁴INFN Sezione di Perugia, Perugia, Italy
³⁵INFN Sezione di Pisa, Pisa, Italy
³⁶INFN Sezione di Roma La Sapienza, Roma, Italy
³⁷INFN Sezione di Roma Tor Vergata, Roma, Italy
³⁸Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands
³⁹Nikhef National Institute for Subatomic Physics and VU University Amsterdam, Amsterdam, Netherlands
⁴⁰AGH—University of Krakow, Faculty of Physics and Applied Computer Science, Kraków, Poland
⁴¹Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland
⁴²National Center for Nuclear Research (NCBJ), Warsaw, Poland
⁴³Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest-Magurele, Romania
⁴⁴Petersburg Nuclear Physics Institute NRC Kurchatov Institute (PNPI NRC KI), Gatchina, Russia
⁴⁵Institute for Nuclear Research of the Russian Academy of Sciences (INR RAS), Moscow, Russia
⁴⁶Institute of Nuclear Physics, Moscow State University (SINP MSU), Moscow, Russia
⁴⁷Institute of Theoretical and Experimental Physics NRC Kurchatov Institute (ITEP NRC KI), Moscow, Russia
⁴⁸Yandex School of Data Analysis, Moscow, Russia
⁴⁹Budker Institute of Nuclear Physics (SB RAS), Novosibirsk, Russia
⁵⁰Institute for High Energy Physics NRC Kurchatov Institute (IHEP NRC KI), Protvino, Russia, Protvino, Russia
⁵¹Universidade da Coruña, A Coruña, Spain
⁵²ICCUB, Universitat de Barcelona, Barcelona, Spain
⁵³La Salle, Universitat Ramon Llull, Barcelona, Spain
⁵⁴Instituto Galego de Física de Altas Enerxías (IGFAE), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
⁵⁵Instituto de Fisica Corpuscular, Centro Mixto Universidad de Valencia—CSIC, Valencia, Spain
⁵⁶European Organization for Nuclear Research (CERN), Geneva, Switzerland
⁵⁷Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
⁵⁸Physik-Institut, Universität Zürich, Zürich, Switzerland
⁵⁹NSC Kharkiv Institute of Physics and Technology (NSC KIPT), Kharkiv, Ukraine
⁶⁰Institute for Nuclear Research of the National Academy of Sciences (KINR), Kyiv, Ukraine
⁶¹School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom
⁶²H.H. Wills Physics Laboratory, University of Bristol, Bristol, United Kingdom
⁶³Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom
⁶⁴Department of Physics, University of Warwick, Coventry, United Kingdom
⁶⁵STFC Rutherford Appleton Laboratory, Didcot, United Kingdom
⁶⁶School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
⁶⁷School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom
⁶⁸Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom
⁶⁹Imperial College London, London, United Kingdom
⁷⁰Department of Physics and Astronomy, University of Manchester, Manchester, United Kingdom
⁷¹Department of Physics, University of Oxford, Oxford, United Kingdom
⁷²Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
⁷³University of Cincinnati, Cincinnati, Ohio, USA
⁷⁴University of Maryland, College Park, Maryland, USA
⁷⁵Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, USA
⁷⁶Syracuse University, Syracuse, New York, USA
⁷⁷Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil (associated with Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil)
⁷⁸Universidad Andres Bello, Santiago, Chile (associated with Physik-Institut, Universität Zürich, Zürich, Switzerland)
⁷⁹School of Physics and Electronics, Hunan University, Changsha City, China (associated with Institution Institute of Particle Physics, Central China Normal University, Wuhan, Hubei, China)
⁸⁰State Key Laboratory of Nuclear Physics and Technology, South China Normal University, Guangzhou, China (associated with Department of Engineering Physics, Tsinghua University, Beijing, China)
⁸¹Lanzhou University, Lanzhou, China (associated with Institute Of High Energy Physics (IHEP), Beijing, China)
⁸²School of Physics and Technology, Wuhan University, Wuhan, China (associated with Department of Engineering Physics, Tsinghua University, Beijing, China)
⁸³Henan Normal University, Xinxiang, China (associated with Institute of Particle Physics, Central China Normal University, Wuhan, Hubei, China)
⁸⁴Departamento de Fisica, Universidad Nacional de Colombia, Bogota, Colombia (associated with Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Sorbonne Université, CNRS/IN2P3, Paris, France)
⁸⁵Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic (associated with Department of Physics and Astronomy, University of Manchester, Manchester, United Kingdom)
⁸⁶Ruhr Universitaet Bochum, Fakultaet f. Physik und Astronomie, Bochum, Germany (associated with Fakultät Physik, Technische Universität Dortmund, Dortmund, Germany)
⁸⁷Eotvos Lorand University, Budapest, Hungary (associated with European Organization for Nuclear Research (CERN), Geneva, Switzerland)
⁸⁸Faculty of Physics, Vilnius University, Vilnius, Lithuania (associated with Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany)
⁸⁹Van Swinderen Institute, University of Groningen, Groningen, Netherlands (associated with Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands)
⁹⁰Universiteit Maastricht, Maastricht, Netherlands (associated with Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands)
⁹¹Tadeusz Kosciuszko Cracow University of Technology, Cracow, Poland (associated with Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland)
⁹²National Research Centre Kurchatov Institute, Moscow, Russia (associated with Institute of Theoretical and Experimental Physics NRC Kurchatov Institute (ITEP NRC KI), Moscow, Russia)
⁹³National Research University Higher School of Economics, Moscow, Russia (associated with Yandex School of Data Analysis, Moscow, Russia)
⁹⁴National University of Science and Technology “MISIS”, Moscow, Russia (associated with Institute of Theoretical and Experimental Physics NRC Kurchatov Institute (ITEP NRC KI), Moscow, Russia)
⁹⁵National Research Tomsk Polytechnic University, Tomsk, Russia (associated with Institute of Theoretical and Experimental Physics NRC Kurchatov Institute (ITEP NRC KI), Moscow, Russia)
⁹⁶Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden (associated with School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom)
⁹⁷Taras Schevchenko University of Kyiv, Faculty of Physics, Kyiv, Ukraine (associated with Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France)
⁹⁸University of Michigan, Ann Arbor, Michigan, USA (associated with Syracuse University, Syracuse, New York, USA)
⁹⁹Ohio State University, Columbus, USA (associated with Los Alamos National Laboratory (LANL), Los Alamos, New Mexico, USA)

^*Full author list given at the end of the article.
^aAlso at Lamarr Institute for Machine Learning and Artificial Intelligence, Dortmund, Germany.
^bAlso at Università degli Studi di Milano-Bicocca, Milano, Italy.
^cAlso at Università di Roma Tor Vergata, Roma, Italy.
^dAlso at Università di Modena e Reggio Emilia, Modena, Italy.
^eAlso at Department of Physics and Astronomy, University of Victoria, Victoria, Canada.
^fAlso at Università di Ferrara, Ferrara, Italy.
^gAlso at Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil.
^hAlso at Università di Bologna, Bologna, Italy.
ⁱAlso at Università di Genova, Genova, Italy.
^jAlso at Scuola Normale Superiore, Pisa, Italy.
^kAlso at Università degli Studi di Milano, Milano, Italy.
^lAlso at Center for High Energy Physics, Tsinghua University, Beijing, China.
^mAlso at Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras.
ⁿAlso at Università di Cagliari, Cagliari, Italy.
^oAlso at Centro Federal de Educacão Tecnológica Celso Suckow da Fonseca, Rio De Janeiro, Brazil.
^pAlso at Università di Bari, Bari, Italy.
^qAlso at Università di Perugia, Perugia, Italy.
^rAlso at LIP6, Sorbonne Université, Paris, France.
^sAlso at Università di Pisa, Pisa, Italy.
^tAlso at Hangzhou Institute for Advanced Study, UCAS, Hangzhou, China.
^uAlso at Novosibirsk State University, Novosibirsk, Russia.
^vAlso at Università di Padova, Padova, Italy.
^wAlso at Università di Bergamo, Bergamo, Italy.
^xAlso at Universidad de Ingeniería y Tecnología (UTEC), Lima, Peru.
^yAlso at Università di Siena, Siena, Italy.
^zAlso at Universidad de Alcalá, Alcalá de Henares, Spain.
^aaAlso at Università di Urbino, Urbino, Italy.

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Phys. Rev. D 113, 072019 – Published 30 April, 2026

DOI: https://doi.org/10.1103/jqvq-sbp7

Abstract

The first observation of the $χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-}$ decay is reported using proton-proton collision data recorded with the LHCb detector corresponding to an integrated luminosity of $9 {fb}^{- 1}$ . The decay mode is observed for the first time, with a significance of $6.5 σ$ . Its branching fraction is measured relative to the $χ_{c 1} (3872) \to J / ψ π^{+} π^{-}$ decay mode $\frac{B (χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-})}{B (χ_{c 1} (3872) \to J / ψ π^{+} π^{-})} = (1.68 \pm 0.32 \pm 0.05) \times 10^{- 3}$ , where the first uncertainty includes both statistical contributions and systematic contributions which are uncorrelated between data-taking periods, and the second represents the systematic contributions that are correlated between data-taking periods.

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Phys. Rev. D 113, 072019– Published 30 April, 2026

Vol. 113, Iss. 7 — 1 April 2026

Received 29 January 2026
Accepted 1 April 2026

DOI: https://doi.org/10.1103/jqvq-sbp7

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Observation of the decay $χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-}$

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Observation of the decay χc1(3872)→J/ψμ+μ−

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Observation of the decay $χ_{c 1} (3872) \to J / ψ μ^{+} μ^{-}$