6533b835fe1ef96bd129f35b

RESEARCH PRODUCT

Improved measurements of two-photon widths of the χcJ states and helicity analysis for χc2→γγ

X. Y. ZhouM. BertaniL. J. WuL. YangY. J. MoX. F. WangA. YuncuA. YuncuK. GoetzenX. K. ZhouX. K. ZhouD. LiuD. LiuQ. M. MaA. MustafaW. B. YanW. B. YanW. GradlM. RipkaD. BettoniX. Y. NiuC. SowaJ. L. ZhangY. YuanY. S. ZhuI. UmanT. WeberD. Y. WangYu ZhangM. KuemmelW. ShanS. ZhuQ. P. JiY. Q. WangM. L. ChenS. NisarC. J. TangY. HuLiqing XuG. ChelkovG. ChelkovG. ChelkovP. L. LiP. L. LiM. H. GuY. P. LuL. YanY. J. MaoP. LarinH. X. YangK. J. ZhuX. Y. ShenI. GarziaD. XiaoL. KochC. LengKai LiuM. DestefanisM. QiA. KhoukazH. J. YangH. J. YangZ. G. ZhaoZ. G. ZhaoW. P. WangW. P. WangQ. LiuX. D. RuanL. L. MaL. GongG. S. HuangG. S. HuangA. AmorosoL. ZhangY. J. SunY. J. SunA. DbeyssiG. F. XuM. KornicerY. PanY. PanR. Baldini FerroliA. JulinS. JinR. KliemtJ. B. JiaoHuihui LiuJ. P. LiuM. AlbrechtX. Y. JiangDan WangH. Y. ShengS. B. LiuS. B. LiuY. K. HengJ. Q. ZhangY. NefedovM. M. MaBibo KeC. HuX. TangY. DingX. L. GaoX. L. GaoJ. G. MesschendorpW. D. LiM. N. AchasovM. N. AchasovB. J. LiuZahra HaddadiC. X. YuV. PrasadY. X. XiaS. H. ZhuB. T. TsedneeX. N. MaZhenan LiuY. T. LiangX. Y. SongM. RoloY. T. ZhangY. T. ZhangJ. P. DaiJ. P. DaiS. Q. ZhangY. H. ZhangS. PacettiQ. OuyangJ. C. LiJie YuTalib HussainJ. F. SunH. J. LuCui LiQ. AnQ. AnB. ZhengR. G. PingQiunan XuJ. J. XuY. X. ZhouY. X. ZhouX. S. JiangL. S. WangJ. ChaiW. KühnG. X. SunJ. V. BennettMing ShaoMing ShaoX. R. ZhouX. R. ZhouZ. Y. YouZ. A. ZhuS. MarcelloF. E. MaasM. FritschD. P. JinI. TapanJ. PellegrinoY. ZengX. K. ChuW. G. LiJ. S. HuangM. X. LuoC. X. LiuD. V. DedovichKe LiS. HanY. H. YanSen QianS. GuO. BakinaM. KavatsyukZ. JiaoFu-hu LiuD. H. ZhangL. L. WangH. CaiG. F. ChenG. Y. TangH. L. DaiM. MaggioraJ. ZhuLing ZhaoQ. P. JiR. PolingP. F. DuanJ. Y. ZhangM. H. YeQ. A. MalikS. SpataroX. P. XuGianfranco MorelloL. ZhouY. Y. LiuP. X. ShenJie ZhaoD. X. LinC. DongH. M. HuJ. B. LiuJ. B. LiuA. ZhemchugovA. ZhemchugovS. SosioFenfen AnB. L. WangC. P. ShenFang LiuO. DorjkhaidavB. KopfB. Y. ZhangI. DenysenkoXiaozhong HuangJun-yi ZhangY. P. GuoK. L. HeS. X. DuXiaofeng ZhuJ. Z. ZhangY. H. YangT. J. MinK. J. ZhuT. C. ZhaoZ. P. ZhangL. D. LiuB. X. ZhangZhiqing ZhangL. H. WuH. XiaoLei ZhaoLei ZhaoZ. L. HouJ. J. SongG. CibinettoZ. L. DouL. SunX. LiuH. R. QiLei LiY. K. SunY. K. SunH. M. LiuL. Y. DongJoachim PetterssonYunpeng LuZ. GaoZ. GaoM. Z. WangZhiyong ZhangT. HeldG. FeliciK. J. LiZ. H. QinJ. MinD. W. BennettZ. G. WangXiao-rui LyuW. J. ZhengZ. WuY. BaiSerkant Ali CetinF. NerlingM. SavrieA. CalcaterraYi JinS. FeganZ. T. SunE. BogerE. BogerG. F. CaoH. Y. ZhangI. B. NikolaevI. B. NikolaevY. G. GaoC. Z. YuanM. KuhlmannH. H. ZhangJ. P. ZhengH. B. LiuY. BanP. WeidenkaffF. H. HeinsiusYao WangJialun PingJ. H. ZouT. KhanT. KhanJ. H. YinK. H. RashidK. H. RashidK. ZhangG. S. VarnerY. T. GuJin LiB. X. YuX. Y. ZhangH. B. LiX. CaiJ. G. LuA. G. DenigC. L. LuoS. P. WenG. R. LiaoS. S. SunY. J. XiaoA. Q. GuoH. S. ChenC. C. ZhangM. LaraB. ZhongL. B. GuoBingxuan LiuBingxuan LiuX. S. QinB. Q. WangE. FioravantiIgor BoykoH. MuramatsuG. LiUlrich WiednerS. L. NiuM. Y. DongJ. ZhuangT. MaX. C. LouX. C. LouO. B. KolcuO. B. KolcuR. E. MitchellC. Q. FengC. Q. FengT. HuY. B. ChenZ. L. HuangFeng LiuJia-jia QinC. D. FuX. L. KangL. XiaL. XiaD. H. WeiP. R. LiP. R. LiM. AblikimJ. S. LangeX. R. ChenZ. Y. DengX. H. MoXingguo LiY. C. ZhuY. C. ZhuM. G. ZhaoJ. Z. BaiR. P. GuoY. H. XieAndrzej KupscX. B. JiM. TiemensP. PatteriP. MusiolC. F. RedmerY. G. XieJ. M. BianC. SchnierX. T. HuangA. A. ZafarS. J. ZhaoG. RongZ. X. MengX. A. XiongQ. J. XuJ. C. ChenW. X. GongZhiqing LiuNasser Kalantar-nayestanakiC. Morales MoralesS. J. ChenT. JohanssonF. C. MaY. B. ZhaoZ. H. WangZ. H. WangJ. F. QiuL. FavaS. AhmedY. X. YangH. J. LiQ. ZhaoY. Z. SunJ. FangXiang ZhouL. LavezziX. L. LuoZ. ZengZ. ZengF. Y. LiX. Q. LiY. F. LongM. GrecoGang ZhaoT. HoltmannX. Q. HaoM. YeM. RichterY. F. WangH. P. PengH. P. PengP. L. WangJ. Y. LiuK. Y. LiuP. L. WangZ. B. LiJing DongW. Ikegami AnderssonQ. GaoY. N. GaoY. ZhangP. KieseS. L. OlsenR. A. BriereJ. Z. FanX. FangX. FangZ. J. XiaoP. L. LiuH. LiangH. LiangL. ZottiX. L. JiF. BianchiO. CakirX. Y. MaR. FarinelliH. LeithoffF. A. HarrisQ. L. XiuJ. Z. ZhaoH. L. MaD. M. LiM. PelizaeusJ. W. ZhangA. SarantsevA. SarantsevX. H. SunZ. WangJ. F. ChangMagnus WolkeY. F. LiangS. S. FangDayong WangN. QinY. B. LiuY. H. ZhengCong-feng QiaoN. Yu. MuchnoiN. Yu. MuchnoiX. S. KangZ. Y. WangF. FeldbauerKe WangKe LiuX. N. LiYaquan FangK. PetersK. PetersJ. W. ZhaoK. SchoenningQ. Y. LiB. S. ZouNiklaus BergerG. MezzadriF. LiCheng LiCheng LiX. Q. HeW. C. YanW. C. YanY. M. MaZ. P. MaoTao LiZ. J. SunCh. RosnerZhe NingF. De Mori

subject

PhysicsAnnihilation010308 nuclear & particles physics0103 physical sciencesAnalytical chemistry010306 general physics01 natural sciencesHelicityGamma gamma

description

Based on 448.1 x 10(6) Psi(3686) events collected with the BESIII detector, the decays Psi(3686) -> gamma chi(cJ), chi(cJ) -> gamma gamma(J = 0, 1, 2) are studied. The decay branching fractions of chi(c0,2) -> gamma gamma are measured to be B(chi(c0) -> gamma gamma) = (1.93 +/- 0.08 +/- 0.05 +/- 0.05) x 10(-4) and B(chi(c2) -> gamma gamma) = (3.10 +/- 0.09 +/- 0.07 +/- 0.11) x 10(-4) which correspond to two-photon decay widths of Gamma(gamma gamma)(chi(c0)) = 2.03 +/- 0.08 +/- 0.06 +/- 0.13 keV and Gamma(gamma gamma)(chi(c2)) = 0.60 +/- 0.02 +/- 0.01 +/- 0.04 keV with a ratio of R = Gamma(gamma gamma)(chi(c2))/Gamma(gamma gamma)(chi(c0)) = 0.295 +/- 0.014 +/- 0.007 +/- 0.027, where the uncertainties are statistical, systematic and associated with the uncertainties of B(Psi(3686) -> gamma chi(c0,2)) and the total widths Gamma(chi(c0,2)), respectively. For the forbidden decay of chi(c1) -> gamma gamma, no signal is observed, and an upper limit on the two-photon width is obtained to be Gamma(gamma gamma)(chi(c1)) gamma gamma is also measured to be f(0/2) = Gamma(lambda=0)(gamma gamma) (chi(c2))/Gamma(lambda=2)(gamma gamma) (chi(c2)) = (0.0 +/- 0.6 +/- 1.2) x 10(-2), where the uncertainties are statistical and systematic, respectively.

https://doi.org/10.1103/physrevd.96.092007