Search for the doubly heavy baryon Ξ_(bc)^(+)→ decaying to J/ψΞ_(c)^(+)  

作　　者：R.Aaij A.S.W.Abdelmotteleb C.Abellan Beteta F.Abudinén T.Ackernley B.Adeva M.Adinolfi H.Afsharnia C.Agapopoulou C.A.Aidala S.Aiola Z.Ajaltouni S.Akar K.Akiba J.Albrecht F.Alessio M.Alexander A.Alfonso Albero Z.Aliouche P.Alvarez Cartelle S.Amato J.L.Amey Y.Amhis L.An L.Anderlini M.Andersson A.Andreianov M.Andreotti D.Andreou D.Ao F.Archilli A.Artamonov M.Artuso E.Aslanides M.Atzeni B.Audurier S.Bachmann M.Bachmayer J.J.Back A.Bailly-reyre P.Baladron Rodriguez V.Balagura W.Baldini J.Baptista de Souza Leite M.Barbetti R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Baryshnikov J.M.Basels G.Bassi B.Batsukh A.Battig A.Bay A.Beck M.Becker F.Bedeschi I.B.Bediaga A.Beiter V.Belavin S.Belin V.Bellee K.Belous I.Belov I.Belyaev G.Bencivenni E.Ben-Haim A.Berezhnoy R.Bernet D.Berninghoff H.C.Bernstein C.Bertella A.Bertolin C.Betancourt F.Betti Ia.Bezshyiko S.Bhasin J.Bhom L.Bian M.S.Bieker N.V.Biesuz S.Bifani P.Billoir A.Biolchini M.Birch F.C.R.Bishop A.Bitadze A.Bizzeti M.P.Blago T.Blake F.Blanc S.Blusk D.Bobulska J.A.Boelhauve O.Boente Garcia T.Boettcher A.Boldyrev N.Bondar S.Borghi M.Borsato J.T.Borsuk S.A.Bouchiba T.J.V.Bowcock A.Boyer C.Bozzi M.J.Bradley S.Braun A.Brea Rodriguez J.Brodzicka A.Brossa Gonzalo D.Brundu A.Buonaura L.Buonincontri A.T.Burke C.Burr A.Bursche A.Butkevich J.S.Butter J.Buytaert W.Byczynski S.Cadeddu H.Cai R.Calabrese L.Calefice S.Cali R.Calladine M.Calvi M.Calvo Gomez P.Camargo Magalhaes P.Campana D.H.Campora Perez A.F.Campoverde Quezada S.Capelli L.Caprio 

机构地区：[1]Centro Brasileiro de Pesquisas Físicas(CBPF),Rio de Janeiro,Brazil [2]Universidade Federal do Rio de Janeiro(UFRJ),Rio de Janeiro,Brazil [3]Center for High Energy Physics,Tsinghua University,Beijing,China [4]Institute Of High Energy Physics(IHEP),Beijing,China [5]School of Physics State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing,China [6]University of Chinese Academy of Sciences,Beijing,China [7]Institute of Particle Physics,Central China Normal University,Wuhan,Hubei,China [8]Université Savoie Mont Blanc,CNRS,IN2P3-LAPP,Annecy,France [9]UniversitéClermont Auvergne,CNRS/IN2P3,LPC,Clermont-Ferrand,France [10]Aix Marseille Univ,CNRS/IN2P3,CPPM,Marseille,France [11]UniversitéParis-Saclay,CNRS/IN2P3,IJCLab,Orsay,France [12]Laboratoire Leprince-Ringuet,CNRS/IN2P3,Ecole Polytechnique,Institut Polytechnique de Paris,Palaiseau,France [13]LPNHE,Sorbonne Université,Paris Diderot Sorbonne Paris Cité,CNRS/IN2P3,Paris,France [14]I.Physikalisches Institut,RWTH Aachen University,Aachen,Germany [15]Fakultät Physik,Technische Universität Dortmund,Dortmund,Germany [16]Max-Planck-Institut für Kernphysik(MPIK),Heidelberg,Germany [17]Physikalisches Institut,Ruprecht-Karls-Universität Heidelberg,Heidelberg,Germany [18]School of Physics,University College Dublin,Dublin,Ireland [19]INFN Sezione di Bari,Bari,Italy [20]INFN Sezione di Bologna,Bologna,Italy [21]INFN Sezione di Ferrara,Ferrara,Italy [22]INFN Sezione di Firenze,Firenze,Italy [23]INFN Laboratori Nazionali di Frascati,Frascati,Italy [24]INFN Sezione di Genova,Genova,Italy [25]INFN Sezione di Milano,Milano,Italy [26]INFN Sezione di Milano-Bicocca,Milano,Italy [27]INFN Sezione di Cagliari,Monserrato,Italy [28]Universitàdegli Studi di Padova,Universitàe INFN,Padova,Padova,Italy [29]INFN Sezione di Pisa,Pisa,Italy [30]INFN Sezione di Roma La Sapienza,Roma,Italy [31]INFN Sezione di Roma Tor Vergata,Roma,Italy [32]Nikhef National Institute for Subatomic Physics,Amsterdam,Netherlands [33]Nikhef National Institute for Subatomic Physics an

出　　处：《Chinese Physics C》2023年第9期1-13,共13页中国物理C（英文版）

基　　金：The project support from CERN and from the national agencies:CAPES,CNPq,FAPERJ and FINEP(Brazil);MOST and NSFC(China);CNRS/IN2P3(France);BMBF,DFG and MPG(Germany);INFN(Italy);NWO(Netherlands);MNiSW and NCN(Poland);MEN/IFA(Romania);MICINN(Spain);SNSF and SER(Switzerland);NASU(Ukraine);STFC(United Kingdom);DOE NP and NSF(USA).We acknowledge the computing resources that are provided by CERN,IN2P3(France),KIT and DESY(Germany),INFN(Italy),SURF(Netherlands),PIC(Spain),GridPP(United Kingdom),CSCS(Switzerland),IFIN-HH(Romania),CBPF(Brazil),Polish WLCG(Poland)and NERSC(USA).Individual groups or members have received support from ARC and ARDC(Australia);Minciencias(Colombia);AvH Foundation(Germany);EPLANET,Marie Sklodowska-Curie Actions and ERC(European Union);A*MIDEX,ANR,IPhU and Labex P2IO,and Région Auvergne-RhôneAlpes(France);Key Research Program of Frontier Sciences of CAS,CAS PIFI,CAS CCEPP,Fundamental Research Funds for the Central Universities,and Sci.&Tech.Program of Guangzhou(China);GVA,XuntaGal,GENCAT and Prog.Atracción Talento,CM(Spain);SRC(Sweden);the Leverhulme Trust,the Royal Society and UKRI(United Kingdom).

摘　　要：A first search for the Ξ_(bc)^(+)J/ψΞ_(c)^(+) decay is performed by the LHCb experiment with a data sample of proton-proton collisions, corresponding to an integrated luminosity of 9 fb−1 recorded at centre-of-mass energies of 7, 8, and 13 TeV. Two peaking structures are seen with a local (global) significance of 4.3(2.8) and 4.1(2.4) standard deviations at masses of 6571 and 6694 MeV/c2, respectively. Upper limits are set on the Ξ+bc baryon production cross-section times the branching fraction relative to that of the B+c→J/ψD+s decay at centre-of-mass energies of 8 and 13 TeV, in the Ξ+bc and in the B+c rapidity and transverse-momentum ranges from 2.0 to 4.5 and 0 to 20GeV/c, respectively. Upper limits are presented as a function of the Ξ+bc mass and lifetime.

关 键 词：QCD B physics charm physics spectroscopy 

分 类 号：O572.3[理学—粒子物理与原子核物理]