Improved Measurements of Two-Photon Widths of The χ(cJ) States and Helicity Analysis For χ(c2) → γγ
| dc.contributor.ORCID | 0000-0003-0867-2189 (Lou, X) | en_US |
| dc.contributor.author | Ablikim, M. | en_US |
| dc.contributor.author | Achasov, M. N. | en_US |
| dc.contributor.author | Ahmed, S. | en_US |
| dc.contributor.author | Albrecht, M. | en_US |
| dc.contributor.author | Amoroso, A. | en_US |
| dc.contributor.author | An, F. F. | en_US |
| dc.contributor.author | An, Q. | en_US |
| dc.contributor.author | Lou, Xinchou | en_US |
| dc.contributor.author | BESIII Collaboration | en_US |
| dc.contributor.utdAuthor | Lou, Xinchou | en_US |
| dc.date.accessioned | 2018-10-01T16:50:57Z | |
| dc.date.available | 2018-10-01T16:50:57Z | |
| dc.date.created | 2017-11-01 | en_US |
| dc.date.issued | 2018-10-01 | |
| dc.description.abstract | Based on 448.1 x 10⁶ ψ(3686) events collected with the BESIII detector, the decays ψ(3686) → γ χ(cJ), χ(cJ) → γγ(J = 0, 1, 2) are studied. The decay branching fractions of χ(c0,2) → γγ are measured to be ℬ(χ(c0) → γγ) = (1.93 ± 0.08 ± 0.05 ± 0.05) x 10⁻⁴ and ℬ(χ(c2) → γγ) = (3.10 ± 0.09 ± 0.07 ± 0.11) x 10⁻⁴ which correspond to two-photon decay widths of Γ(γγ)(χ(c0)) = 2.03 ± 0.08 ± 0.06 ± 0.13 keV and Γ(γγ)(χ(c2)) = 0.60 ± 0.02 ± 0.01 ± 0.04 keV with a ratio of R = Γ(γγ)(χ(c2))/Γ(γγ)(χ(c0)) = 0.295 ± 0.014 ± 0.007 ± 0.027, where the uncertainties are statistical, systematic and associated with the uncertainties of ℬ(ψ(3686) → γχ(c2)) and the total widths Γχ(c0,2), respectively. For the forbidden decay of χ(c1) → γγ, no signal is observed, and an upper limit on the two-photon width is obtained to be Γ(γγ)(χ(c1)) < 5.3 eV at the 90% confidence level. The ratio of the two-photon widths between helicity-zero and helicity-two components in the decay χ(c2) → γγ is also measured to be f(0/2) = Γ(γγ)(λ=0) (χ(c2)) / Γ(γγ)(λ=2) (χ(c2) = (0.0 ± 0.6 ± 1.2) x 10(-2), where the uncertainties are statistical and systematic, respectively. | en_US |
| dc.description.department | School of Natural Sciences and Mathematics | en_US |
| dc.description.sponsorship | "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 Nos. 11235011, 11322544, 11335008, 11425524, 11635010; the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; the CAS Center for Excellence in Particle Physics (CCEPP); the Collaborative Innovation Center for Particles and Interactions (CICPI); Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contracts Nos. U1232201, U1332201, U1532257, U1532258; CAS under Contracts Nos. KJCX2-YW-N29, KJCX2-YW-N45; 100 Talents Program of CAS; National 1000 Talents Program of China; INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology; German Research Foundation DFG under Contracts Nos. Collaborative Research Center CRC 1044, FOR 2359; 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 Swedish Resarch Council; U.S. Department of Energy under Contracts Nos. DE-FG02-05ER41374, DE-SC-0010118, DE-SC-0010504, DE-SC-0012069; University of Groningen (RuG) and the Helmholtzzentrum fuer Schwerionenforschung GmbH (GSI), Darmstadt; WCU Program of National Research Foundation of Korea under Contract No. R32-2008-000-10155-0." | en_US |
| dc.identifier.bibliographicCitation | Ablikim, M., M. N. Achasov, S. Ahmed, M. Albrecht, et al. 2017. "Improved measurements of two-photon widths of the χ(cJ) states and helicity analysis for χ(c2) → γγ." Physical Review D 96(9), doi:10.1103/PhysRevD.96.092007 | en_US |
| dc.identifier.issn | 2470-0010 | en_US |
| dc.identifier.issue | 9 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10735.1/6176 | |
| dc.identifier.volume | 96 | en_US |
| dc.language.iso | en | en_US |
| dc.publisher | Amer Physical Soc | en_US |
| dc.relation.uri | http://dx.doi.org/10.1103/PhysRevD.96.092007 | |
| dc.rights | ©2017 American Physical Society. All Rights Reserved. | en_US |
| dc.source | Physical Review D | |
| dc.subject | Quarkoniums | en_US |
| dc.subject | Annihilation (Nuclear reactions) | en_US |
| dc.subject | Particles (Nuclear physics) | en_US |
| dc.subject | Electron-positron interactions | en_US |
| dc.subject | Branching fractions (Nuclear physics) | en_US |
| dc.subject | Photons--Decay | en_US |
| dc.title | Improved Measurements of Two-Photon Widths of The χ(cJ) States and Helicity Analysis For χ(c2) → γγ | en_US |
| dc.type.genre | article | en_US |