期刊
PHYSICAL REVIEW D
卷 99, 期 1, 页码 -出版社
AMER PHYSICAL SOC
DOI: 10.1103/PhysRevD.99.012006
关键词
-
资金
- National Key Basic Research Program of China [2015CB856700]
- National Natural Science Foundation of China (NSFC) [11235011, 11322544, 11335008, 11375170, 11275189, 11425524, 11475164, 11475169, 11625523, 11605196, 11605198, 11635010, 11705192]
- Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program
- CAS Center for Excellence in Particle Physics (CCEPP)
- NSFC [U1332201, U1532257, U1532258, U1532102]
- CAS [U1332201, U1532257, U1532258, U1532102, KJCX2-YW-N29, KJCX2-YW-N45, QYZDJ-SSW-SLH003]
- 100 Talents Program of CAS
- National 1000 Talents Program of China
- INPAC
- Shanghai Key Laboratory for Particle Physics and Cosmology
- German Research Foundation DFG [CRC 1044, FOR 2359]
- Instituto Nazionale di Fisica Nucleare, Italy
- NSFC
- CAS
- Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) [530-4CDP03]
- Ministry of Development of Turkey [DPT2006K-120470]
- National Natural Science Foundation of China (NSFC)
- National Science and Technology fund
- Swedish Research Council
- U.S. Department of Energy [DE-FG02-05ER41374, DE-SC-0010118, DE-SC-0010504, DE-SC-0012069]
- University of Groningen (RuG)
- Helmholtzzentrum fuer Schwerionenforschung GmbH (GSI), Darmstadt
- WCU Program of National Research Foundation of Korea [R32-2008-000-10155-0]
We study the electromagnetic Dalitz decay J/psi -> e(+)e(-)eta and search for dielectron decays of a dark gauge boson (gamma') in J/psi -> gamma'eta with the two q decay modes eta -> gamma gamma and eta -> pi(+)pi(-)pi(0) using (1310.6 +/- 7.0) x 10(6) J/psi events collected with the BESIII detector. The branching fraction of J/psi -> e(+)e(-)eta is measured to be (1.43 +/- 0.04(stat) +/- 0.06(syst)) x 10(-5), with a precision that is improved by a factor of 1.5 over the previous BESIII measurement. The corresponding dielectron invariant mass dependent modulus square of the transition form factor is explored for the first time, and the pole mass is determined to be Lambda = 2.84 +/- 0.11(stat) +/- 0.08(syst) GeV/c(2). We find no evidence of gamma' production and set 90% confidence level upper limits on the product branching fraction B(J/psi -> gamma'eta) x B(gamma' -> e(+)e(-)) as well as the kinetic mixing strength between the standard model photon and gamma' in the mass range of 0.01 <= m(gamma') <= 2.4 GeV/c(2).
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据