Using inclusive decays of J/ψ aprecise determination of the number of J/ψ events collected with the BESIII detector was performed.For the two data sets taken in 2009 and 2012,the numbers of J/ψ events were recalcul...Using inclusive decays of J/ψ aprecise determination of the number of J/ψ events collected with the BESIII detector was performed.For the two data sets taken in 2009 and 2012,the numbers of J/ψ events were recalculated to be(224.0±1.3)×10^(6) and(1088.5±4.4)×10^(6),respectively;these numbers are in good agreement with the previous measurements. For the J/ψ sample taken in 2017-2019,the number of events was determined to be(8774.0±39.4)×10^(6).The total number of J/ψ events collected with the BESIII detector was determined to be(10087±44)×10^(6),where the uncertainty is dominated by systematic effects,and the statistical uncertainty is negligible.展开更多
The world＇s largest sample of J/ψ events, 1.31 billion events accumulated at the BESIII detector, provides a unique opportunity to investigate η and η physics via two-body J/ψ radiative or hadronic decays. For ma...The world＇s largest sample of J/ψ events, 1.31 billion events accumulated at the BESIII detector, provides a unique opportunity to investigate η and η physics via two-body J/ψ radiative or hadronic decays. For many η decay channels the low background data samples are up to three orders of magnitude larger than collected in any previous experiment. Here we review the most significant results on η and η obtained at BESIII so far. The analyses range from detailed studies of common decay dynamics, observations of new radiative and Dalitz decays, and searches for rare/forbidden decays with sensitivity up to B～10-5. Finally, prospects of forthcoming runs at the J/ψ peak forη and η physics are discussed.展开更多
Based on J/ψ events collected with the BESIII detector,with corresponding Monte Carlo samples,the tracking efficiency and its systematic uncertainty are studied using a control sample of J/ψ→pp^-π＋π^-.Validation...Based on J/ψ events collected with the BESIII detector,with corresponding Monte Carlo samples,the tracking efficiency and its systematic uncertainty are studied using a control sample of J/ψ→pp^-π＋π^-.Validation methods and different factors influencing the tracking efficiency are presented in detail.The tracking efficiency and its systematic uncertainty for protons and pions with the transverse momentum and polar angle dependence are also discussed.展开更多
The calibration algorithm for RPC-based muon detector at BESIII has been developed. The calibration method, calibration error and algorithm performance are studied. The primary results of efficiency and noise at layer...The calibration algorithm for RPC-based muon detector at BESIII has been developed. The calibration method, calibration error and algorithm performance are studied. The primary results of efficiency and noise at layer, module and strip levels have been calibrated with cosmic ray data. The calibration constants are available for simulation and reconstruction tuning. The results of Monte Carlo and data are also compared to check the validation and reliability of the algorithm.展开更多
Using(448.1±2.9)×10^(6)ψ(3686)for the weak baryonic decayψ(3686)→Λc+∑-+c.c..The analysis procedure is optimized using a blinded method.No significant signal is observed,and the upper limit on the branch...Using(448.1±2.9)×10^(6)ψ(3686)for the weak baryonic decayψ(3686)→Λc+∑-+c.c..The analysis procedure is optimized using a blinded method.No significant signal is observed,and the upper limit on the branching fraction(B)ofψ(3686)→Λc+∑-+c.c.is set as 1.4×10^(-5)at the 90%confidence level.展开更多
基金Supported in part by National Key R&D Program of China(2020YFA0406300, 2020YFA0406400)National Natural Science Foundation of China(NSFC)(11625523, 11635010, 11735014, 11822506, 11835012, 11935015, 11935016, 11935018, 11961141012, 12022510, 12025502, 12035009, 12035013,12061131003,12075252)+16 种基金the Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility ProgramJoint Large-Scale Scientific Facility Funds of the NSFC and CAS(U1732263, U1832207)CAS Key Research Program of Frontier Sciences(QYZDJ-SSW-SLH040)100 Talents Program of CASINPAC and Shanghai Key Laboratory for Particle Physics and CosmologyERC(758462)European Union Horizon 2020 research and innovation programme Marie Sklodowska-Curie grant agreement(894790)German Research Foundation DFG(443159800), Collaborative Research Center CRC 1044, FOR 2359, GRK 214Istituto Nazionale di Fisica Nucleare, ItalyMinistry of Development of Turkey under Contract No. DPT2006K-120470National Science and Technology fundOlle Engkvist Foundation(200-0605)STFC(United Kingdom)The Knut and Alice Wallenberg Foundation(Sweden)(2016.0157)The Royal Society, UK(DH140054, DH160214)The Swedish Research CouncilU. S. Department of Energy(DE-FG02-05ER41374, DE-SC-0012069)
文摘Using inclusive decays of J/ψ aprecise determination of the number of J/ψ events collected with the BESIII detector was performed.For the two data sets taken in 2009 and 2012,the numbers of J/ψ events were recalculated to be(224.0±1.3)×10^(6) and(1088.5±4.4)×10^(6),respectively;these numbers are in good agreement with the previous measurements. For the J/ψ sample taken in 2017-2019,the number of events was determined to be(8774.0±39.4)×10^(6).The total number of J/ψ events collected with the BESIII detector was determined to be(10087±44)×10^(6),where the uncertainty is dominated by systematic effects,and the statistical uncertainty is negligible.
基金Supported by National Natural Science Foundation of China(NSFC)(11565006,11675184,11735014)
文摘The world＇s largest sample of J/ψ events, 1.31 billion events accumulated at the BESIII detector, provides a unique opportunity to investigate η and η physics via two-body J/ψ radiative or hadronic decays. For many η decay channels the low background data samples are up to three orders of magnitude larger than collected in any previous experiment. Here we review the most significant results on η and η obtained at BESIII so far. The analyses range from detailed studies of common decay dynamics, observations of new radiative and Dalitz decays, and searches for rare/forbidden decays with sensitivity up to B～10-5. Finally, prospects of forthcoming runs at the J/ψ peak forη and η physics are discussed.
基金Supported by Joint Funds of National Natural Science Foundation of China(U1232201)National Natural Science Foundation of China(11275210,11205182,11205184)National Key Basic Research Program of China(2015CB856700)
文摘Based on J/ψ events collected with the BESIII detector,with corresponding Monte Carlo samples,the tracking efficiency and its systematic uncertainty are studied using a control sample of J/ψ→pp^-π＋π^-.Validation methods and different factors influencing the tracking efficiency are presented in detail.The tracking efficiency and its systematic uncertainty for protons and pions with the transverse momentum and polar angle dependence are also discussed.
基金Supported by CAS Knowledge Innovation Project(U-602, U-34)National Natural Science Foundation of China (10491300,10491303, 10605030, 10835001, 10821063)+1 种基金100 Talents Program of CAS (U-25 and U-54)National Basic Research Program of China (2009CB825208)
文摘The calibration algorithm for RPC-based muon detector at BESIII has been developed. The calibration method, calibration error and algorithm performance are studied. The primary results of efficiency and noise at layer, module and strip levels have been calibrated with cosmic ray data. The calibration constants are available for simulation and reconstruction tuning. The results of Monte Carlo and data are also compared to check the validation and reliability of the algorithm.
基金supported in part by National Key Research and Development Program of China(2020YFA0406400,2020YFA0406300)National Natural Science Foundation of China(NSFC,11975118,11635010,11735014,11835012,11935015,11935016,11935018,11961141012,12022510,12025502,12035009,12035013,12192260,12192261,12192262,12192263,12192264,12192265,12061131003)+18 种基金the Natural Science Foundation of Hunan Province of China(2019JJ30019)the Science and Technology Innovation Program of Hunan Province(2020RC3054)the Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility ProgramJoint Large-Scale Scientific Facility Funds of the NSFC and CAS(U1832207)CAS Key Research Program of Frontier Sciences(QYZDJ-SSW-SLH040)100 Talents Program of CASThe Institute of Nuclear and Particle Physics(INPAC)and Shanghai Key Laboratory for Particle Physics and Cosmology,ERC(758462)European Union’s Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant agreement(894790)German Research Foundation DFG(443159800)Collaborative Research Center CRC 1044,GRK 2149Istituto Nazionale di Fisica Nucleare,ItalyMinistry of Development of Turkey(DPT2006K-120470)National Science and Technology fundNational Science Research and Innovation Fund(NSRF)via the Program Management Unit for Human Resources and Institutional Development,Research and Innovation(B16F640076)STFC(United Kingdom)Suranaree University of Technology(SUT),Thailand Science Research and Innovation(TSRI),and National Science Research and Innovation Fund(NSRF,160355)The Royal Society,UK(DH140054,DH160214)The Swedish Research CouncilU.S.Department of Energy(DE-FG02-05ER41374)。
文摘Using(448.1±2.9)×10^(6)ψ(3686)for the weak baryonic decayψ(3686)→Λc+∑-+c.c..The analysis procedure is optimized using a blinded method.No significant signal is observed,and the upper limit on the branching fraction(B)ofψ(3686)→Λc+∑-+c.c.is set as 1.4×10^(-5)at the 90%confidence level.
