6533b7d6fe1ef96bd1265aaf

RESEARCH PRODUCT

Two-photon widths of theχc0,2states and helicity analysis forχc2→γγ

M. MaggioraLing ZhaoTao LuoY. F. WangC. NicholsonZ. Y. HeZ. L. HouYang YangB. X. YuH. B. LiX. Y. MaM. UllrichW. X. GongA. G. DenigC. L. LuoZhiqing LiuYuanbo ChenX. L. LuoG. M. XuC. Z. YuanC. C. ZhangH. J. LuJ. G. LuB. ZhongL. B. GuoH. S. ChenJ. F. ChangLei LiY. DingShujun ZhaoK. GoetzenW. KuehnH. L. DaiIgor BoykoShan WangF. E. MaasUlrich WiednerC. H. LiG. F. XuT. MaYanping HuangS. JinW. B. YanS. MaG. R. LuX. CaiX. R. LiX. Y. SongJ. M. BianZhenyu ZhangW. LaiD. TothT. HuM. QiZ. A. ZhuSanfeng WuG. S. VarnerHang LiuP. WangM. N. AchasovE. H. ThorndikeX. L. WangB. WangX. T. LiaoMichael WernerJ. S. HuangC. X. LiuXiangdong RuanS. PacettiD. H. SunH. L. TianF. LiX. H. LiuLei ZhaoGuangming HuangZ. NingQ. J. XuA. CalcaterraZ. G. ZhaoL. S. WangC. S. JiF. C. MaJ. C. ChenM. L. ChenBrent J. LiuM. Z. WangJ. P. DaiX. Q. LiZ. WuZ. J. SunM. GrecoL. G. XiaH. LoehnerYu-bin LiuH. LiangY. NefedovX. L. JiX. N. LiL. ZhangH. H. LiuC. L. MaY. X. YangJ. C. LiKun LiuKe WangJ. K. C. LeungH. H. LiuX. K. ZhouT. YangJ. ZhuangNasser Kalantar-nayestanakiC. Morales MoralesM. PelizaeusX. SunH. H. ZhangM. X. LuoRinaldo Baldini FerroliJ. F. QiuD. V. DedovichQ. P. JiN. B. LiR. PolingV. V. BytevH. X. YangH.s. XuM. R. ShepherdS. H. ZhangX. Y. ShenFenfen AnX. Q. HaoX. TangJ. F. SunZhenli XuQ. ZhaoS. P. YuG. A. ChelkovG. A. ChelkovTalib HussainY. Z. SunChun S. J. PunS. B. LiuC. MotzkoT. C. ZhaoK. Y. LiuK. X. ZhaoC. GengY. ZengM. Y. DongL. L. JiangZhe SunY. G. XieY. F. LiangD. P. JinS. J. ChenGang ZhaoJ. MinH. B. LiuG. X. SunLi YanJulian SchulzeS. X. DuF. A. HarrisY. B. ChenXiaofeng ZhuJ. Z. ZhangO. BondarenkoX. F. WangXiao-tong LuJoong-won ParkM. G. ZhaoJ. P. LiuL. FavaL. FavaJ. Q. ZhangY. M. ZhuZ. JiaoFu-hu LiuD. H. ZhangS. L. OlsenRoy A. BriereP. L. LiuJ. H. ZouX. S. JiangN. WuKrisztian PetersY. H. ZhengH. L. MaXiaobo ZhuCong-feng QiaoD. M. LiQ. M. MaL. K. JiaK. L. HeZ. G. WangH. Y. ZhangN. Yu. MuchnoiYin XuP. L. WangQi-wen LüS. S. SunJ. G. MesschendorpQ. L. XiuB. Q. WangHeng-yun YeC. P. ShenC. P. ShenJ. X. ZuoL. H. WuShou-hua ZhuY. YuanY. S. ZhuY. H. ZhangG. F. ChenJ. Z. BaiJ. Y. ZhangQ. G. WenY. J. MaoY.n. GaoZ. Y. WangM. BertaniJürgen BeckerB. S. ZouG. R. LiaoR. E. MitchellY. K. HengZhiqiang LiuMiao HeZujian WangA. Q. GuoY. P. ChuL. P. ZhouK. LiY. M. MaY. S. ZhangFang LiuX. B. JiW. GradlZ. P. MaoF. F. JingH. P. ChengJ. FangI. DenysenkoB. Y. ZhangY. ZhangQ. AnZ. H. QinB. SpruckX. H. ZhaoWei WuA. ZhemchugovA. ZhemchugovChuan LiuW. L. YuanQ. OuyangW. G. LiS. SpataroY. Q. WangX. P. XuC. ZhuH. M. LiuJ. F. HuS. S. FangG. F. CaoG. LiY. B. ZhaoX. T. HuangM. AblikimK. J. ZhuY. B. LiuXuantong ZhangC. D. FuA. A. ZafarG. RongC. Q. FengZ. Y. DengXingguo LiC. J. TangY. P. LuQ. A. MalikKai LiuJie YuZ. P. ZhengT. J. MinK. J. ZhuF. FeldbauerFeng LiuChang LiuT. R. ZhangY. L. HanY. T. LiangHongsheng ZhaoQ. J. WangJianping ZhengM. LvJ. G. ZhangZ. XueZ. B. LiM. DestefanisJ. ZhangM. KavatsyukB. X. ZhangH. MaoJ. B. JiaoJ. ZhongYao WangZhiyong ZhangX. LiuZ. J. XiaoY. P. GuoS. QianJialun PingL. L. WangX. Y. ZhangY. J. SunE. BogerE. BogerD. J. AmbroseM. H. GuH. Y. ShengC. X. YuB. ZhengR. G. PingE. PrencipeQun-yao WangW. D. LiFeng XueCui LiZ. A. LiuY. BanP. WeidenkaffS. L. LiY. H. YanJ. W. ZhaoD. Cronin-hennessyS. P. WenX. S. QinT. HeldX. R. ZhouJ. L. FuCheng LiI. B. NikolaevK. H. RashidM. ShaoY. T. GuQ. J. LiZ. H. AnA. SarantsevA. SarantsevD. H. WeiJ. S. LangeB. HuangX. H. MoM. H. YeM. H. YeL. Y. DongH. M. HuW. M. DingNicolas BergerJ. W. ZhangA. ZalloYang QinY. H. Guan

subject

PhysicsNuclear physicsNuclear and High Energy PhysicsAnnihilationElectron–positron annihilationLambdaWidth ratioHelicityEvent generatorGamma gamma

description

Based on a data sample of 106 X 10(6) psi' events collected with the BESIII detector, the decays psi' -> gamma chi(c0,2), chi(c0,2) -> gamma gamma are studied to determine the two-photon widths of the chi(c0,2) states. The two-photon decay branching fractions are determined to be B(chi(c0) -> gamma gamma) = (2.24 +/- 0.19 +/- 0.12 +/- 0.08) X 10(-4) and B(chi(c2) -> gamma gamma) = (3.21 +/- 0.18 +/- 0.17 +/- 0.13) X 10(-4) From these, the two-photon widths are determined to be Gamma(gamma gamma)(chi(c0)) = (2.33 +/- 0.20 +/- 0.13 +/- 0.17) keV, Gamma(gamma gamma)(chi(c2)) = (0.63 +/- 0.04 +/- 0.04 +/- 0.04) keV, and R = Gamma(gamma gamma)(chi(c2))/Gamma(gamma gamma)(chi(c0)) = 0.271 +/- 0.029 +/- 0.013 +/- 0.027, where the uncertainties are statistical, systematic, and those from the PDG B(psi' -> gamma chi(c0,2)) and Gamma(chi(c0,2)) errors, respectively. The ratio of the two-photon widths for helicity lambda = 0 and helicity lambda = 2 components in the decay chi -> gamma gamma is measured for the first time to be f(0/2) = Gamma(lambda=0)(gamma gamma)(chi(c2))/Gamma(lambda=2)(gamma gamma)(chi(c2)) = 0.00 +/- 0.02 +/- 0.02.

https://doi.org/10.1103/physrevd.85.112008