# First evidence for the decay B(s)(0)→μ+ μ-.

@article{Aaij2013FirstEF, title={First evidence for the decay B(s)(0)→$\mu$+ $\mu$-.}, author={R. Aaij and C. Abell{\'a}n Beteta and A. Adametz and B. Adeva and M. Adinolfi and C. Adrover and A. Affolder and Z. Ajaltouni and J. Albrecht and F. Alessio and M. Alexander and S. Ali and G. Alkhazov and P. Alvarez Cartelle and A. A. Alves and S. Amato and Y. Amhis and L. Anderlini and J. Anderson and R. Andreassen and R. Appleby and O. Aquines Gutierrez and F. Archilli and A. Artamonov and M. Artuso and E. Aslanides and G. Auriemma and S. Bachmann and J. Back and C. Baesso and W. Baldini and R. Barlow and C. Barschel and S. Barsuk and W. Barter and A. Bates and T. Bauer and A. Bay and J. Beddow and I. Bediaga and S. Belogurov and K. Belous and I. Belyaev and E. Ben-Haim and M. Benayoun and G. Bencivenni and S. Benson and J. Benton and A. Berezhnoy and R. Bernet and M. Bettler and M. van Beuzekom and A. Bie{\~n} and S. Bifani and T. Bird and A. Bizzeti and P. Bj{\o}rnstad and T. Blake and F. Blanc and C. Blanks and J. Blouw and S. Blusk and A. Bobrov and V. Bocci and A. Bondar and N. Bondar and W. Bonivento and S. Borghi and A. Borgia and T. Bowcock and E. Bowen and C. Bozzi and T. Brambach and J. V. D. van den Brand and J. Bressieux and D. Brett and M. Britsch and T. Britton and N. Brook and H. Brown and A. B{\"u}chler-Germann and I. Burducea and A. Bursche and J. Buytaert and S. Cadeddu and O. Callot and M. Calvi and M. Calvo Gomez and A. Camboni and P. Campana and A. Carbone and G. Carboni and R. Cardinale and A. Cardini and H. Carranza-Mejia and L. Carson and K. Carvalho Akiba and G. Casse and M. Cattaneo and C. Cauet and M. Charles and P. Charpentier and P. Chen and N. Chiapolini and M. Chrzaszcz and K. Ciba and X. Cid Vidal and G. Ciezarek and P. Clarke and M. Clemencic and H. Cliff and J. Closier and C. Coca and V. Coco and J. Cogan and E. Cogneras and P. Collins and A. Comerma-Montells and A. Contu and A. Cook and M. Coombes and G. Corti and B. Couturier and G. Cowan and D. Craik and S. Cunliffe and R. Currie and C. D’Ambrosio and P. David and I. de Bonis and K. De Bruyn and S. de Capua and M. De Cian and J. De Miranda and L. de Paula and P. de Simone and D. Decamp and M. Deckenhoff and H. Degaudenzi and L. Del Buono and C. Deplano and D. Derkach and O. Deschamps and F. Dettori and A. Di Canto and J. Dickens and H. Dijkstra and P. Diniz Batista and M. Dogaru and F. Domingo Bonal and S. Donleavy and F. Dordei and P. Dornan and A. Dosil Su{\'a}rez and D. Dossett and A. Dovbnya and F. Dupertuis and R. Dzhelyadin and A. Dziurda and A. Dzyuba and S. Easo and U. Egede and V. Egorychev and S. Eidelman and D. van Eijk and S. Eisenhardt and R. Ekelhof and L. Eklund and I. El Rifai and C. Elsasser and D. Elsby and A. Falabella and C. F{\"a}rber and G. Fardell and C. Farinelli and S. Farry and V. Fave and V. Fernandez Albor and F. Ferreira Rodrigues and M. Ferro-Luzzi and S. Filippov and C. Fitzpatrick and M. Fontana and F. Fontanelli and R. Forty and O. Francisco and M. Frank and C. Frei and M. Frosini and S. Furcas and A. Gallas Torreira and D. Galli and M. Gandelman and P. Gandini and Y. Gao and J. Garofoli and P. Garosi and J. Garra Tic{\'o} and L. Garrido and C. Gaspar and R. Gauld and E. Gersabeck and M. Gersabeck and T. Gershon and P. Ghez and V. Gibson and V. Gligorov and C. G{\"o}bel and D. Golubkov and A. Golutvin and A. Gomes and H. Gordon and M. Grabalosa G{\'a}ndara and R. Graciani Diaz and L. Granado Cardoso and E. Grauges and G. Graziani and A. Grecu and E. Greening and S. Gregson and O. Gr{\"u}nberg and B. Gui and E. Gushchin and Y. Guz and T. Gys and C. Hadjivasiliou and G. Haefeli and C. Haen and S. Haines and S. Hall and T. Hampson and S. Hansmann-Menzemer and N. Harnew and S. Harnew and J. Harrison and P. Harrison and T. Hartmann and J. He and V. Heijne and K. Hennessy and P. Henrard and J. A. Hernando Morata and E. van Herwijnen and E. Hicks and D. Hill and M. Hoballah and P. H. Hopchev and P. Hopchev and W. Hulsbergen and P. Hunt and T. Huse and N. Hussain and D. Hutchcroft and D. Hynds and V. Iakovenko and P. Ilten and J. Imong and R. Jacobsson and A. Jaeger and E. Jans and F. Jansen and P. Jaton and F. Jing and M. John and D. Johnson and C. Jones and B. Jost and M. Kaballo and S. Kandybei and M. Karacson and T. M. Karbach and I. Kenyon and U. Kerzel and T. Ketel and A. Keune and B. Khanji and O. Kochebina and V. Komarov and R. Koopman and P. Koppenburg and M. Korolev and A. Kozlinskiy and L. Kravchuk and K. Kreplin and M. Kreps and G. Krocker and P. Krokovny and F. Kruse and M. Kucharczyk and V. Kudryavtsev and T. Kvaratskheliya and V. N. La Thi and D. Lacarr{\`e}re and G. Lafferty and A. Lai and D. Lambert and R. Lambert and E. Lanciotti and G. Lanfranchi and C. Langenbruch and T. Latham and C. Lazzeroni and R. Le Gac and J. van Leerdam and J. Lees and R. Lef{\`e}vre and A. Leflat and J. Lefrancois and O. Leroy and T. Lesiak and Y. Li and L. Li Gioi and M. Liles and R. Lindner and C. Linn and B. Liu and G. Liu and J. von Loeben and J. Lopes and E. Lopez Asamar and N. Lopez-march and H. Lu and J. Luisier and H. Luo and A. Mac Raighne and F. Machefert and I. Machikhiliyan and F. Maciuc and O. Maev and M. Maino and S. Malde and G. Manca and G. Mancinelli and N. Mangiafave and U. Marconi and R. M{\"a}rki and J. Marks and G. Martellotti and A. Martens and L. Martin and A. M. Mart{\'i}n S{\'a}nchez and M. Martinelli and D. Mart{\'i}nez Santos and D. Martins Tostes and A. Massafferri and R. Matev and Z. M{\'a}th{\'e} and C. Matteuzzi and M. Matveev and E. Maurice and A. Mazurov and J. P. McCarthy and R. McNulty and B. Meadows and M. Meissner and M. Merk and D. Milanes and M. Minard and J. M. Molina Rodr{\'i}guez and S. Monteil and D. Moran and P. Morawski and R. Mountain and I. Mous and F. Muheim and K. M{\"u}ller and R. Mureşan and B. Muryn and B. Muster and P. Naik and T. Nakada and R. Nandakumar and I. Nasteva and M. Needham and N. Neufeld and A. Nguyen and T. Nguyen and C. Nguyen-Mau and M. Nicol and V. Niess and N. Nikitin and T. Nikodem and S. Nisar and A. Nomerotski and A. Novoselov and A. Oblakowska-Mucha and V. Obraztsov and S. Oggero and S. Ogilvy and O. Okhrimenko and R. Oldeman and M. Orlandea and J. Otalora Goicochea and P. Owen and B. Pal and A. Palano and M. Palutan and J. Panman and A. Papanestis and M. Pappagallo and C. Parkes and C. Parkinson and G. Passaleva and G. Patel and M. Patel and G. Patrick and C. Patrignani and C. Pavel-Nicorescu and A. Pazos Alvarez and A. Pellegrino and G. Penso and M. Pepe Altarelli and S. Perazzini and D. Perego and E. Perez Trigo and A. P{\'e}rez-Calero Yzquierdo and P. Perret and M. Perrin-Terrin and G. Pessina and K. Petridis and A. Petrolini and A. Phan and E. Picatoste Olloqui and B. Pietrzyk and T. Pilař and D. Pinci and S. Playfer and M. Pl{\'o} Casas{\'u}s and F. Polci and G. Polok and A. Poluektov and E. Polycarpo and D. Popov and B. Popovici and C. Potterat and A. Powell and J. Prisciandaro and V. Pugatch and A. Puig Navarro and W. Qian and J. Rademacker and B. Rakotomiaramanana and M. Rangel and I. Raniuk and N. Rauschmayr and G. Raven and S. Redford and M. Reid and A. dos Reis and S. Ricciardi and A. Richards and K. Rinnert and V. Rives Molina and D. A. Roa Romero and P. Robbe and E. Rodrigues and P. Rodriguez Perez and G. Rogers and S. Roiser and V. Romanovsky and A. Romero Vidal and J. Rouvinet and T. Ruf and H. Ruiz and G. Sabatino and J. Saborido Silva and N. Sagidova and P. Sail and B. Saitta and C. Salzmann and B. Sanmartin Sedes and M. Sannino and R. Santacesaria and C. Santamarina Rios and E. Santovetti and M. Sapunov and A. Sarti and C. Satriano and A. Satta and M. Savri{\'e} and P. Schaack and M. Schiller and H. Schindler and S. Schleich and M. Schlupp and M. Schmelling and B. Schmidt and O. Schneider and A. Schopper and M. Schune and R. Schwemmer and B. Sciascia and A. Sciubba and M. Seco and A. Semennikov and K. Senderowska and I. Sepp and N. Serra and J. Serrano}, journal={Physical review letters}, year={2013}, volume={110 2}, pages={ 021801 } }

A search for the rare decays B(s)(0)→μ+ μ- and B(0)→μ+ μ- is performed with data collected in 2011 and 2012 with the LHCb experiment at the Large Hadron Collider. The data samples comprise 1.1 fb(-1) of proton-proton collisions at sqrt[s]=8 TeV and 1.0 fb(-1) at sqrt[s]=7 TeV. We observe an excess of B(s)(0)→μ+ μ- candidates with respect to the background expectation. The probability that the background could produce such an excess or larger is 5.3×10(-4) corresponding to a signal… Expand

#### 217 Citations

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