Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Measurement of the branching fraction of and search for a CP -violating asymmetry in η′ →π+π-e+e- At BESIII. / The BESIII Collaboration.
в: Physical Review D, Том 103, № 9, 092005, 19.05.2021.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Measurement of the branching fraction of and search for a CP -violating asymmetry in η′ →π+π-e+e- At BESIII
AU - BESIII Collaboration
AU - Ablikim, M.
AU - Achasov, M. N.
AU - Adlarson, P.
AU - Ahmed, S.
AU - Albrecht, M.
AU - Amoroso, A.
AU - An, Q.
AU - Bai, X. H.
AU - Bai, Y.
AU - Bakina, O.
AU - Ferroli, R. Baldini
AU - Balossino, I.
AU - Ban, Y.
AU - Begzsuren, K.
AU - Bennett, J. V.
AU - Berger, N.
AU - Bertani, M.
AU - Bettoni, D.
AU - Bianchi, F.
AU - Biernat, J.
AU - Bloms, J.
AU - Bortone, A.
AU - Boyko, I.
AU - Briere, R. A.
AU - Cai, H.
AU - Cai, X.
AU - Calcaterra, A.
AU - Cao, G. F.
AU - Cao, N.
AU - Cetin, S. A.
AU - Chang, J. F.
AU - Chang, W. L.
AU - Chelkov, G.
AU - Chen, D. Y.
AU - Chen, G.
AU - Chen, H. S.
AU - Chen, M. L.
AU - Chen, S. J.
AU - Chen, X. R.
AU - Chen, Y. B.
AU - Chen, Z. J.
AU - Cheng, W. S.
AU - Cibinetto, G.
AU - Cossio, F.
AU - Cui, X. F.
AU - Dai, H. L.
AU - Dai, J. P.
AU - Dai, X. C.
AU - Muchnoi, N. Yu
AU - Nikolaev, I. B.
N1 - Funding Information: The BESIII collaboration thanks the staff of BEPCII and the IHEP computing center for their strong support. This work is supported in part by National Key Basic Research Program of China under Contract No. 2015CB856700; National Natural Science Foundation of China (NSFC) under Contracts No. 11625523, No. 11635010, No. 11735014, No. 11675184; National Natural Science Foundation of China (NSFC) under Contract No. 11835012; the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contracts No. U1532257, No. U1532258, No. U1732263, No. U1832207; CAS Key Research Program of Frontier Sciences under Contracts No. QYZDJ-SSW-SLH003, No. QYZDJ-SSW-SLH040; 100 Talents Program of CAS; INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology; German Research Foundation DFG under Contract No. Collaborative Research Center CRC 1044; Istituto Nazionale di Fisica Nucleare, Italy; Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) under Contract No. 530-4CDP03; Ministry of Development of Turkey under Contract No. DPT2006K-120470; National Science and Technology fund; The Knut and Alice Wallenberg Foundation (Sweden) under Contract No. 2016.0157; The Royal Society, UK under Contract No. DH160214; The Swedish Research Council; U.S. Department of Energy under Contracts No. DE-FG02-05ER41374, No. DE-SC-0010118, No. DE-SC-0012069; University of Groningen (RuG); The Helmholtzzentrum fuer Schwerionenforschung GmbH (GSI), Darmstadt and the Olle Engkvist Foundation (Sweden) under Contract No. 200-0605. Publisher Copyright: © 2021 authors. Published by the American Physical Society. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/5/19
Y1 - 2021/5/19
N2 - The rare decay η′→π+π-e+e- is studied using a sample of 1.3×109 J/ψ events collected with the BESIII detector at BEPCII in 2009 and 2012. The branching fraction is measured with improved precision to be (2.42±0.05stat±0.08syst)×10-3. Due to the inclusion of new data, this result supersedes the last BESIII result on this branching fraction. In addition, the CP-violating asymmetry in the angle between the decay planes of the π+π - pair and the e+e - pair is investigated. A measurable value would indicate physics beyond the standard model; the result is ACP=(2.9±3.7stat±1.1syst)%, which is consistent with the standard model expectation of no CP-violation. The precision is comparable to the asymmetry measurement in the KL0→π+π-e+e- decay where the observed (14±2)% effect is driven by a standard model mechanism.
AB - The rare decay η′→π+π-e+e- is studied using a sample of 1.3×109 J/ψ events collected with the BESIII detector at BEPCII in 2009 and 2012. The branching fraction is measured with improved precision to be (2.42±0.05stat±0.08syst)×10-3. Due to the inclusion of new data, this result supersedes the last BESIII result on this branching fraction. In addition, the CP-violating asymmetry in the angle between the decay planes of the π+π - pair and the e+e - pair is investigated. A measurable value would indicate physics beyond the standard model; the result is ACP=(2.9±3.7stat±1.1syst)%, which is consistent with the standard model expectation of no CP-violation. The precision is comparable to the asymmetry measurement in the KL0→π+π-e+e- decay where the observed (14±2)% effect is driven by a standard model mechanism.
UR - http://www.scopus.com/inward/record.url?scp=85106959157&partnerID=8YFLogxK
U2 - 10.1103/PhysRevD.103.092005
DO - 10.1103/PhysRevD.103.092005
M3 - Article
AN - SCOPUS:85106959157
VL - 103
JO - Physical Review D
JF - Physical Review D
SN - 2470-0010
IS - 9
M1 - 092005
ER -
ID: 28715277