Aaij R, Adeva B, Adinolfi M, Ajaltouni Z, Akar S, Albrecht J, Alessio F, Alexander M, Ali S, Alkhazov G, Alvarez Cartelle P, Alves A A, Amato S, Amerio S, Amhis Y, An L, Anderlini L, Andreassi G, Andreotti M, Andrews J E, Appleby R B, Archilli F, d'Argent P, Arnau Romeu J, Artamonov A, Artuso M, Aslanides E, Auriemma G, Baalouch M, Babuschkin I, Bachmann S, Back J J, Badalov A, Baesso C, Baker S, Balagura V, Baldini W, Baranov A, Barlow R J, Barschel C, Barsuk S, Barter W, Baryshnikov F, Baszczyk M, Batozskaya V, Batsukh B, Battista V, Bay A, Beaucourt L, Beddow J, Bedeschi F, Bediaga I, Beiter A, Bel L J, Bellee V, Belloli N, Belous K, Belyaev I, Ben-Haim E, Bencivenni G, Benson S, Beranek S, Berezhnoy A, Bernet R, Bertolin A, Betancourt C, Betti F, Bettler M-O, van Beuzekom M, Bezshyiko Ia, Bifani S, Billoir P, Birnkraut A, Bitadze A, Bizzeti A, Blake T, Blanc F, Blouw J, Blusk S, Bocci V, Boettcher T, Bondar A, Bondar N, Bonivento W, Bordyuzhin I, Borgheresi A, Borghi S, Borisyak M, Borsato M, Bossu F, Boubdir M, Bowcock T J V, Bowen E, Bozzi C, Braun S, Britton T, Brodzicka J, Buchanan E, Burr C, Bursche A, Buytaert J, Cadeddu S, Calabrese R, Calvi M, Calvo Gomez M, Camboni A, Campana P, Campora Perez D H, Capriotti L, Carbone A, Carboni G, Cardinale R, Cardini A, Carniti P, Carson L, Carvalho Akiba K, Casse G, Cassina L, Castillo Garcia L, Cattaneo M, Cavallero G, Cenci R, Chamont D, Charles M, Charpentier Ph, Chatzikonstantinidis G, Chefdeville M, Chen S, Cheung S F, Chobanova V, Chrzaszcz M, Chubykin A, Cid Vidal X, Ciezarek G, Clarke P E L, Clemencic M, Cliff H V, Closier J, Coco V, Cogan J, Cogneras E, Cogoni V, Cojocariu L, Collins P, Comerma-Montells A, Contu A, Cook A, Coombs G, Coquereau S, Corti G, Corvo M, Costa Sobral C M, Couturier B, Cowan G A, Craik D C, Crocombe A, Cruz Torres M, Cunliffe S, Currie R, D'Ambrosio C, Da Cunha Marinho F, Dall'Occo E, Dalseno J, David P N Y, Davis A, De Bruyn K, De Capua S, De Cian M, De Miranda J M, De Paula L, De Serio M, De Simone P, Dean C T, Decamp D, Deckenhoff M, Del Buono L, Demmer M, Dendek A, Derkach D, Deschamps O, Dettori F, Dey B, Di Canto A, Dijkstra H, Dordei F, Dorigo M, Dosil Suárez A, Dovbnya A, Dreimanis K, Dufour L, Dujany G, Dungs K, Durante P, Dzhelyadin R, Dziurda A, Dzyuba A, Déléage N, Easo S, Ebert M, Egede U, Egorychev V, Eidelman S, Eisenhardt S, Eitschberger U, Ekelhof R, Eklund L, Ely S, Esen S, Evans H M, Evans T, Falabella A, Farley N, Farry S, Fay R, Fazzini D, Ferguson D, Fernandez G, Fernandez Prieto A, Ferrari F, Ferreira Rodrigues F, Ferro-Luzzi M, Filippov S, Fini R A, Fiore M, Fiorini M, Firlej M, Fitzpatrick C, Fiutowski T, Fleuret F, Fohl K, Fontana M, Fontanelli F, Forshaw D C, Forty R, Franco Lima V, Frank M, Frei C, Fu J, Funk W, Furfaro E, Färber C, Gallas Torreira A, Galli D, Gallorini S, Gambetta S, Gandelman M, Gandini P, Gao Y, Garcia Martin L M, García Pardiñas J, Garra Tico J, Garrido L, Garsed P J, Gascon D, Gaspar C, Gavardi L, Gazzoni G, Gerick D, Gersabeck E, Gersabeck M, Gershon T, Ghez Ph, Gianì S, Gibson V, Girard O G, Giubega L, Gizdov K, Gligorov V V, Golubkov D, Golutvin A, Gomes A, Gorelov I V, Gotti C, Govorkova E, Graciani Diaz R, Granado Cardoso L A, Graugés E, Graverini E, Graziani G, Grecu A, Greim R, Griffith P, Grillo L, Gruberg Cazon B R, Grünberg O, Gushchin E, Guz Yu, Gys T, Göbel C, Hadavizadeh T, Hadjivasiliou C, Haefeli G, Haen C, Haines S C, Hamilton B, Han X, Hansmann-Menzemer S, Harnew N, Harnew S T, Harrison J, Hatch M, He J, Head T, Heister A, Hennessy K, Henrard P, Henry L, van Herwijnen E, Heß M, Hicheur A, Hill D, Hombach C, Hopchev P H, Huard Z-C, Hulsbergen W, Humair T, Hushchyn M, Hutchcroft D, Idzik M, Ilten P, Jacobsson R, Jalocha J, Jans E, Jawahery A, Jiang F, John M, Johnson D, Jones C R, Joram C, Jost B, Jurik N, Kandybei S, Karacson M, Kariuki J M, Karodia S, Kecke M, Kelsey M, Kenzie M, Ketel T, Khairullin E, Khanji B, Khurewathanakul C, Kirn T, Klaver S, Klimaszewski K, Klimkovich T, Koliiev S, Kolpin M, Komarov I, Koppenburg P, Kosmyntseva A, Kotriakhova S, Kozeiha M, Kravchuk L, Kreplin K, Kreps M, Krokovny P, Kruse F, Krzemien W, Kucewicz W, Kucharczyk M, Kudryavtsev V, Kuonen A K, Kurek K, Kvaratskheliya T, Lacarrere D, Lafferty G, Lai A, Lanfranchi G, Langenbruch C, Latham T, Lazzeroni C, Le Gac R, van Leerdam J, Leflat A, Lefrançois J, Lefèvre R, Lemaitre F, Lemos Cid E, Leroy O, Lesiak T, Leverington B, Li T, Li Y, Li Z, Likhomanenko T, Lindner R, Lionetto F, Liu X, Loh D, Longstaff I, Lopes J H, Lucchesi D, Lucio Martinez M, Luo H, Lupato A, Luppi E, Lupton O, Lusiani A, Lyu X, Machefert F, Maciuc F, Maev O, Maguire K, Malde S, Malinin A, Maltsev T, Manca G, Mancinelli G, Manning P, Maratas J, Marchand J F, Marconi U, Marin Benito C, Marinangeli M, Marino P, Marks J, Martellotti G, Martin M, Martinelli M, Martinez Santos D, Martinez Vidal F, Martins Tostes D, Massacrier L M, Massafferri A, Matev R, Mathad A, Mathe Z, Matteuzzi C, Mauri A, Maurice E, Maurin B, Mazurov A, McCann M, McNab A, McNulty R, Meadows B, Meier F, Melnychuk D, Merk M, Merli A, Michielin E, Milanes D A, Minard M-N, Mitzel D S, Mogini A, Molina Rodriguez J, Monroy I A, Monteil S, Morandin M, Morawski P, Morello M J, Morgunova O, Moron J, Morris A B, Mountain R, Muheim F, Mulder M, Mussini M, Müller D, Müller J, Müller K, Müller V, Naik P, Nakada T, Nandakumar R, Nandi A, Nasteva I, Needham M, Neri N, Neubert S, Neufeld N, Neuner M, Nguyen T D, Nguyen-Mau C, Nieswand S, Niet R, Nikitin N, Nikodem T, Nogay A, Novoselov A, O'Hanlon D P, Oblakowska-Mucha A, Obraztsov V, Ogilvy S, Oldeman R, Onderwater C J G, Otalora Goicochea J M, Otto A, Owen P, Oyanguren A, Pais P R, Palano A, Palutan M, Papanestis A, Pappagallo M, Pappalardo L L, Pappenheimer C, Parker W, Parkes C, Passaleva G, Pastore A, Patel M, Patrignani C, Pearce A, Pellegrino A, Penso G, Pepe Altarelli M, Perazzini S, Perret P, Perrin-Terrin M, Pescatore L, Petridis K, Petrolini A, Petrov A, Petruzzo M, Picatoste Olloqui E, Pietrzyk B, Pikies M, Pinci D, Pistone A, Piucci A, Placinta V, Playfer S, Plo Casasus M, Poikela T, Polci F, Poli Lener M, Poluektov A, Polyakov I, Polycarpo E, Pomery G J, Ponce S, Popov A, Popov D, Popovici B, Poslavskii S, Potterat C, Price E, Prisciandaro J, Prouve C, Pugatch V, Puig Navarro A, Punzi G, Qian C, Qian W, Quagliani R, Rachwal B, Rademacker J H, Rama M, Ramos Pernas M, Rangel M S, Raniuk I, Ratnikov F, Raven G, Redi F, Reichert S, Dos Reis A C, Remon Alepuz C, Renaudin V, Ricciardi S, Richards S, Rihl M, Rinnert K, Rives Molina V, Robbe P, Rodrigues A B, Rodrigues E, Rodriguez Lopez J A, Rodriguez Perez P, Rogozhnikov A, Roiser S, Rollings A, Romanovskiy V, Romero Vidal A, Ronayne J W, Rotondo M, Rudolph M S, Ruf T, Ruiz Valls P, Saborido Silva J J, Sadykhov E, Sagidova N, Saitta B, Salustino Guimaraes V, Sanchez Gonzalo D, Sanchez Mayordomo C, Sanmartin Sedes B, Santacesaria R, Santamarina Rios C, Santimaria M, Santovetti E, Sarti A, Satriano C, Satta A, Saunders D M, Savrina D, Schael S, Schellenberg M, Schiller M, Schindler H, Schlupp M, Schmelling M, Schmelzer T, Schmidt B, Schneider O, Schopper A, Schreiner H F, Schubert K, Schubiger M, Schune M-H, Schwemmer R, Sciascia B, Sciubba A, Semennikov A, Sergi A, Serra N, Serrano J, Sestini L, Seyfert P, Shapkin M, Shapoval I, Shcheglov Y, Shears T, Shekhtman L, Shevchenko V, Siddi B G, Silva Coutinho R, Silva de Oliveira L, Simi G, Simone S, Sirendi M, Skidmore N, Skwarnicki T, Smith E, Smith I T, Smith J, Smith M, Soares Lavra L, Sokoloff M D, Soler F J P, Souza De Paula B, Spaan B, Spradlin P, Sridharan S, Stagni F, Stahl M, Stahl S, Stefko P, Stefkova S, Steinkamp O, Stemmle S, Stenyakin O, Stevens H, Stoica S, Stone S, Storaci B, Stracka S, Stramaglia M E, Straticiuc M, Straumann U, Sun L, Sutcliffe W, Swientek K, Syropoulos V, Szczekowski M, Szumlak T, T'Jampens S, Tayduganov A, Tekampe T, Tellarini G, Teubert F, Thomas E, van Tilburg J, Tilley M J, Tisserand V, Tobin M, Tolk S, Tomassetti L, Tonelli D, Topp-Joergensen S, Toriello F, Tourinho Jadallah Aoude R, Tournefier E, Tourneur S, Trabelsi K, Traill M, Tran M T, Tresch M, Trisovic A, Tsaregorodtsev A, Tsopelas P, Tully A, Tuning N, Ukleja A, Ustyuzhanin A, Uwer U, Vacca C, Vagnoni V, Valassi A, Valat S, Valenti G, Vazquez Gomez R, Vazquez Regueiro P, Vecchi S, van Veghel M, Velthuis J J, Veltri M, Veneziano G, Venkateswaran A, Verlage T A, Vernet M, Vesterinen M, Viana Barbosa J V, Viaud B, Vieira D, Vieites Diaz M, Viemann H, Vilasis-Cardona X, Vitti M, Volkov V, Vollhardt A, Voneki B, Vorobyev A, Vorobyev V, Voß C, de Vries J A, Vázquez Sierra C, Waldi R, Wallace C, Wallace R, Walsh J, Wang J, Ward D R, Wark H M, Watson N K, Websdale D, Weiden A, Whitehead M, Wicht J, Wilkinson G, Wilkinson M, Williams M, Williams M P, Williams M, Williams T, Wilson F F, Wimberley J, Winn M A, Wishahi J, Wislicki W, Witek M, Wormser G, Wotton S A, Wraight K, Wyllie K, Xie Y, Xing Z, Xu Z, Yang Z, Yang Z, Yao Y, Yin H, Yu J, Yuan X, Yushchenko O, Zarebski K A, Zavertyaev M, Zhang L, Zhang Y, Zhelezov A, Zheng Y, Zhu X, Zhukov V, Zucchelli S
European Organization for Nuclear Research (CERN), Geneva, Switzerland.
Universidad de Santiago de Compostela, Santiago de Compostela, Spain.
Phys Rev Lett. 2017 May 12;118(19):191801. doi: 10.1103/PhysRevLett.118.191801. Epub 2017 May 11.
A search for the rare decays B_{s}^{0}→μ^{+}μ^{-} and B^{0}→μ^{+}μ^{-} is performed at the LHCb experiment using data collected in pp collisions corresponding to a total integrated luminosity of 4.4 fb^{-1}. An excess of B_{s}^{0}→μ^{+}μ^{-} decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(B_{s}^{0}→μ^{+}μ^{-})=(3.0±0.6_{-0.2}^{+0.3})×10^{-9}, where the first uncertainty is statistical and the second systematic. The first measurement of the B_{s}^{0}→μ^{+}μ^{-} effective lifetime, τ(B_{s}^{0}→μ^{+}μ^{-})=2.04±0.44±0.05 ps, is reported. No significant excess of B^{0}→μ^{+}μ^{-} decays is found, and a 95% confidence level upper limit, B(B^{0}→μ^{+}μ^{-})<3.4×10^{-10}, is determined. All results are in agreement with the standard model expectations.
利用大型强子对撞机底夸克实验（LHCb实验）收集的质心能量为(7)TeV的质子-质子（(pp)）对撞数据（对应总积分亮度为(4.4)fb⁻¹），对稀有衰变(B_{s}^{0}→μ^{+}μ^{-})和(B^{0}→μ^{+}μ^{-})进行了研究。观测到(B_{s}^{0}→μ^{+}μ^{-})衰变存在超出预期的现象，显著性为(7.8)个标准差，这是在单个实验中首次观测到这种衰变。测得分支比为(B(B_{s}^{0}→μ^{+}μ^{-})=(3.0±0.6_{-0.2}^{+0.3})×10^{-9})，其中第一个不确定度是统计性的，第二个是系统性的。报告了对(B_{s}^{0}→μ^{+}μ^{-})有效寿命的首次测量结果，(τ(B_{s}^{0}→μ^{+}μ^{-})=2.04±0.44±0.05)ps。未发现(B^{0}→μ^{+}μ^{-})衰变有显著超出预期的情况，并确定了(95%)置信水平的上限(B(B^{0}→μ^{+}μ^{-})<3.4×10^{-10})。所有结果均与标准模型的预期相符。
