Measurement of the CP asymmetry in B\u2212\u2009\u2192\u2009Ds\u2212D0 and B\u2212 \u2192 D\u2212D0 decays

A Baranov,I Bediaga,A Poluektov,D Maisuzenko,L Ferreira Lopes,O G Girard,S Ely,S Koliiev,A Sergi,A Vitkovskiy,G J Pomery,W Hu,M Reboud,C Hasse,M Vitti,A Bondar,K Müller,T Latham,S Braun,A Birnkraut,D Hill,G Panshin,C D’Ambrosio,C Voß,L M Garcia Martin,A Danilina,X Liang,H Dijkstra,N Bondar,D Brundu,M G Chapman,R Waldi,Y Amhis,C Göbel,F Fleuret,T H Hancock,I Belyaev,M Gersabeck,R Oldeman,B Delaney,S Stemmle,G Dujany,M Idzik,O Stenyakin,N Kazeev,S Didenko,R Quagliani,K E Kim,Z Xu,T Nakada,V Battista,Y Xie,A Petrov,P Stefko,J Molina Rodriguez,F Ferrari,L Eklund,L Douglas,J Müller,E Price,N Farley,B Khanji,S Bifani,P Ciambrone,G Pietrzyk,D Loh,T Schmelzer,K A Zarebski,C Vázquez Sierra,A Ene,H Yin,M Whitehead,S Gianí,B G Siddi,B Maurin,D P O’Hanlon,F Dettori,M W Majewski,J M Kariuki,A Beiter,M Clemencic,P Carniti,C T Dean,F Redi,Z Ajaltouni,A Berezhnoy,L Grillo,M Kolpin,N Meinert,A Sarti,W Byczynski,J P Grabowski,M Demmer,M Vernet,H Viemann,N Belloli,E Maurice,S Benson,F Bedeschi,N Nikitin,K Klimaszewski,J Walsh,T Ketel,J Cogan,M S Rudolph,A Weiden,M Alexander,M Schellenberg,K Petridis,M John,M Pikies,L Gruber,S Maddrell-Mander,V Pugatch,M Kenzie,R Lefèvre,A Dosil Suárez,M Kelsey,G Lafferty,L Anderlini,J Sun,D Johnson,V Batozskaya,G Coombs,S Valat,E Graverini,M Stepanova,M Schubiger,A K Kuonen,S Escher,M Vieites Diaz,T Li,J J Saborido Silva,M Kecke,Y Wang,F Kress,A Loi,V Müller,D Fazzini,A Tayduganov,O Grünberg,O Morgunova,S Strokov,T Shears,P Albicocco,L Tomassetti,V Placinta,A Carbone,M Frank,M Hatch,D Gerick,S Neubert,D Popov,W Barter,H Stevens,J H Rademacker,M Martinelli,W Krupa,J Lefrançois,M Zavertyaev,M Stahl,G Casse,S Stefkova,M E Stramaglia,E Gersabeck,A Chubykin,C Meaux,S Beranek,S Akar,K Dreimanis,M Wang,L J Bel,A Camboni,E Bertholet,V Cogoni,S Stone,J Wang,T Mombächer,D Gascon,T Likhomanenko,X Zhu,M Adinolfi,V Romanovskiy,P.-R Li,M Artuso,I T Smith,C Weisser,M Williams,Z Tang,A Lupato,D Dutta,M Dziewiecki,H M Wark,A Crocombe,N Serra,C Vacca,A B Morris,R Kopecna,L Henry,M Petruzzo,Z Wang,K Gizdov,P Mackowiak,T Evans,D Müller,A Pellegrino,F Meier,D Marangotto,M Kreps,M Marinangeli,S Amato,V Coco,A Usachov,S Nieswand,V Lisovskyi,M Cattaneo,Y Yao,A Comerma-Montells,J B Zonneveld,R Greim,M Santimaria,T Szumlak,D S Mitzel,S Ponce,R Cardinale,T Williams,A Rollings,L Minzoni,X Liu,J M Durham,V Renaudin,M Atzeni,W Hulsbergen,A Mathad,S Chen,S Stahl,L Sestini,A Nogay,T Gershon,J Qin,T Hadavizadeh,T Tekampe,U Marconi,F Pisani,S Cadeddu,W Kucewicz,M Schiller,L Federici,L An,T Blake,A Mauri,P Ilten,E Michielin,V Balagura,B Sciascia,J Buytaert,A Cardini,P Robbe,M Kozeiha,S Gambetta,R Forty,A Bizzeti,C Gotti,B Adeva,G Simi,M Heß,L Gavardi,M Hushchyn,S T’Jampens,K Hennessy,L Zhang,D Berninghoff,B Saitta,A Dendek,M Neuner,G Chatzikonstantinidis,H Pullen,G Morello,A Robert,N Harnew,R Calladine,E Dall’Occo,A Popov,L Cojocariu,D H Campora Perez,C Frei,E Luppi,A Heister,M Calvi,A Nandi,M Traill,P D’Argent,S Barsuk,A Merli,L Capriotti,M Brodski,O Deschamps,M Fontana,Z Yang,O Leroy,M Bjørn,M Winn,A Vagner,E Khairullin,C Burr,F Archilli,J Albrecht,N Neri,F Keizer,M Wilkinson,M Mulder,E Graugés,P Billoir,T Colombo,F Lionetto,J F Marchand,M J Tilley,G Sarpis,M Hecker,S Bachmann,S Eisenhardt,N Polukhina,P Koppenburg,A Venkateswaran,D Hutchcroft,Y Zheng,A Ossowska,T Fiutowski,A Tully,M Smith,S Kotriakhova,Z Li,D Golubkov,S Borghi,L Cassina,K Heinicke,K Maguire,A Mogini,A Piucci,R Bernet,J J Velthuis,A Pastore,C Betancourt,E Aslanides,F Baryshnikov,M Borisyak,P Ibis,T Maltsev,G Andreassi,G Gazzoni,M Morandin,E Gabriel,F Betti,S Poslavskii,G Penso,R Aaij,F Alessio,A Trisovic,E Buchanan,K Rinnert,D Pereima,C Nguyen-Mau,N Beliy,T Skwarnicki,C Färber,M Firlej,B Quintana,W Funk,M Borsato,S Richards,B Meadows,T Humair,N Jurik,M Chefdeville,A Mcnab,E Millard,F Ratnikov,P H Hopchev,J Brodzicka,L Dufour,J García Pardiñas,A Papanestis,D R Ward,S Filippov,Wenqian Huang ,A Lusiani,E Thomas,P Fernandez Declara,E S Sepulveda,A Hicheur,M Andreotti,B Pietrzyk,L Giubega,F Maciuc,G Valenti,E Tournefier,S Ricciardi,O Boente García ,M De Serio,V Chobanova,E Cogneras,O Maev,F Machefert,M Xu,M Ramos Pernas,V Maćko ,R Dzhelyadin,M Van Beuzekom,S Coquereau,I Gorelov ,G Wormser,M J Charles ,P E L Clarke,S Perazzini,B Rachwal,W Krzemień ,A Lai,M Tresch,F Polci,M Dorigo,J A De Vries,O Schneider,T Kirn,C Haen,F Muheim,M Tobin,E Santovetti,S Ali,M Pappagallo,R A Fini,M H Schune,X R Lyu ,B Garcia Plana,D Websdale,Ph Ghez,R Niet,G Raven,L Soares Lavra,A Schopper,S Baker,L L Pappalardo,D Lacarrère ,E Ben-Haim,G A Cowan,P Griffith,X Cid Vidal,F Fontanelli,B Storaci,S Easo,V Bocci,U Uwer,R Ekelhof,S Tolk,L Pescatore,M Karacson,M Schmelling,H Evans ,B Schmidt,T Lesiak,M Needham,K Wyllie,F Bossú ,P Pais ,P Di Nezza,I A Monroy,A Vorobyev,G Haefeli,C L Da Silva,A Bursche,P Seyfert,A Vollhardt,D Savrina,J V Viana Barbosa,M Ferro‐Luzzi ,D Melnychuk,S Blusk,R Lindner,A Grecu,R Schwemmer,D A Milanes,J Marks,M.-N Minard,C Satriano,I Nasteva,A Pearce,S Monteil,S De Capua,F F Wilson,A Golutvin,T Boettcher,P Vázquez Regueiro ,К Ившин ,A Gomes,Ph Charpentier,A Valassi,A Ustyuzhanin,A Mazurov,T J V Bowcock,F Lemaître ,A Sciubba,A Falabella,B Leverington,P Alvarez Cartelle,R Mcnulty,C M Costa Sobral,E Bowen,M Mccann,B Couturier,J H Lopes,P Marino,G Auriemma,M Shapkin,A Contu,U Straumann,S Karodia,C Remon Alepuz,D Martínez Santos ,M Ravonel Salzgeber,K Carvalho Akiba,A Dovbnya,A Fernández Prieto ,X Vilasís-Cardona ,C Matteuzzi,E Rodrigues,L Garrido,C Hadjivasiliou,J Ruiz Vidal,M Corvo,B R Gruberg Cazon,J Wimberley,M Boubdir,M Pló Casasús ,R Le Gac,A Pistone,V Shevchenko,C Joram,H Cai,А Артамонов ,G Fernández ,O De Aguiar Francisco,M D Sokoloff,G Cavallero,P Krokovny,V Kudryavtsev,C Lazzeroni,H F Schreiner,C Gaspar,M Vesterinen,S.-G Chitic,H Schindler,P Campana,F Teubert,J Beddow,J Arnau Romeu,A Davis,R Santacesaria,J Wicht,M Rama,D Vieira,S Schael,D Lucchesi,I Longstaff,A Puig Navarro,S Vecchi,A Satta,M Calvo Gomez,S C Haines,G Graziani,Yongsheng Gao ,G Veneziano,G Passaleva,R Nandakumar,R Vazquez Gomez,M Cruz Torres,S Playfer,L Carson,Y Shcheglov,C Santamarina Ríos ,C Fitzpatrick,W Parker,M Patel,A A Alves,M De Cian,M Szymański ,F Martínez Vidal ,V Salustino Guimarães ,M Palutan,J Closier,H.-P Dembinski,C Patrignani,P De Simone,M Poli Lener,J Serrano,V Gibson,P Naik,U Egede,V Obraztsov,G Ciezarek,Feng Jiang ,Yu Guz,S Malde,D Pinci,Q N Xu ,Y Zhang,I Polyakov,J Prisciandaro,Wenbin Qian ,L Silva De Oliveira,R Silva Coutinho,T Kvaratskheliya,E Polycarpo,O Yushchenko,C Bozzi,J Wishahi,J S Yu ,R Cenci,S Ogilvy,M Van Veghel,D Tonelli,J Jałocha ,C J G Onderwater,J M De Miranda,J Fu,A Oyanguren,P Lenisa,B Vöneki ,А Малинин ,P Durante,S Reichert,S Eidelman,S Roiser,Z Máthé ,W Wiślicki ,N Neufeld,R Graciani Diaz,G Martellotti,W Baldini,G Punzi,S Esen,B Spaan,F Ferreira Rodrigues,R Matev,R Currie,D Chamont,V Tisserand,T D Nguyen,C Khurewathanakul,V Vagnoni,L De Paula,C Potterat,R Calabrese,T Ruf,V Franco Lima,A Jawahery,G Manca,N Sagidova,D Galli,A C Dos Reis,M Lucio Martínez ,S A Wotton,P Perret,M Aldaya Martin ,A Petrolini,S Klaver,G Corti,C Langenbruch,A Palano,M Pepe Altarelli,K De Bruyn,M Kucharczyk,A Bay,R B Appleby,G Wilkinson,R Mountain,C Parkes,J Garra Tico,G Mancinelli,B Hamilton,C R Jones,M Witek,M Chrząszcz ,A B Rodrigues,A Dziurda,G Alkhazov,James Vincent Mead ,D Xiao,P Owen,A Obłąkowska-Mucha ,Е Говоркова ,S Hansmann-Menzemer,M T Tran,E Jans,B Jost,F Marinho ,O Lupton,N Tuning,J J Back,N K Watson,C Marín Benito ,F Blanc,H V Cliff,E Gushchin,T Gys,J Moroń ,J Van Tilburg,R Tourinho Jadallah Aoude,G Carboni,M Gandelman,M J Morello,S Simone,F J P Soler,P Gandini,J E Andrews,L A Granado Cardoso,G Bencivenni,A Dzyuba,A Leflat,D C Craik,U Eitschberger,B Małecki ,J He,A Alfonso Albero,S Amerio,B Souza De Paula,Z Huard ,M Merk,L Del Buono,V Volkov,M Rotondo,J A Rodriguez Lopez,G Tellarini,Vladimir Gligorov ,F Dordei,A Rogozhnikov,K Świentek ,A Gallas Torreira,A Tsaregorodtsev,S Gallorini,L Sun,A Zhelezov,A Di Canto,X Han,M O Bettler,P Collins,O Steinkamp,A Ukleja,C Prouvé ,T Verlage ,C Sánchez Mayordomo ,S Stracka,T Klimkovich,S Farry,L Kravchuk,K Belous,M S Rangel,A Massafferri,Ao Xu ,B Sanmartin Sedes,V Syropoulos,X Yuan,В Жуков ,S Kandybei,J M Otalora Goicochea,V Bellée ,M Straticiuc,A Romero Vidal,A Semennikov,G Lanfranchi,V Egorychev,J Maratas,E Van Herwijnen,Ia Bezshyiko,M Fiorini,Д Деркач ,R J Barlow,F Stagni,R Jacobsson,V Vorobyev,B Dey,M Veltri,J Dalseno,P Spradlin,D Décamp ,S T Harnew,N Skidmore,A Bertolin,L Shekhtman,S Zucchelli

doi:10.1007/jhep05(2018)160

Abstract

The CP asymmetry in B− → Ds−D0 and B− → D−D0 decays is measured using LHCb data corresponding to an integrated luminosity of 3.0 fb−1, collected in pp collisions at centre-of-mass energies of 7 and 8 TeV. The results are {mathcal{A}}^{CP}left({B}^{-}to {D}_s^{-}{D}^0right)=left(-0.4pm 0.5pm 0.5right)%kern0.5em mathrm{and}kern0.5em {mathcal{A}}^{CP}left({B}^{-}to {D}^{-}{D}^0right)=left(2.3pm 2.7pm 0.4right)% , where the first uncertainties are statistical and the second systematic. This is the first measurement of {mathcal{A}}^{CP}left({B}^{-}to {D}_s^{-}{D}^0right) and the most precise determination of {mathcal{A}}^{CP}left({B}^{-}to {D}^{-}{D}^0right) . Neither result shows evidence of CP violation.

Highlights

The determinations of ACP (B− → D(−s)D0) are based on the measurements of the raw asymmetries
The tracking system provides a measurement of momentum, p, of charged particles with a relative uncertainty that varies from 0.5% at low momentum to 1.0% at 200 GeV/c
The decay products from each vertex are constrained to originate from a common vertex, the B− vertex is constrained to originate from the associated primary vertex (PV), and the invariant masses of the D0 and the D(−s) mesons are constrained to their known masses [34], To reduce the combinatorial background, while keeping the signal efficiency as large as possible, a multivariate selection based on a boosted decision tree (BDT) [37, 38] is applied

Summary

The LHCb collaboration

Precise measurements of the CP asymmetry in B− → D−D0 decays are from the Belle and BaBar experiments, ACP = (0 ± 8 ± 2)% [16] and ACP = (−13 ± 14 ± 2)% [17], respectively, where the first uncertainties are statistical and the second systematic. The CP asymmetry in B− → Ds−D0 decays has not been measured before. B− → D−D0 decays, using pp collision data corresponding to an integrated luminosity of

TeV and

Detector and simulation

Candidate selection

Measurement of the raw asymmetries

Production and detection asymmetries

Results and conclusions