Production of χc1 in e +e − collision

Authors

  • Tong Liu Fudan University

DOI:

https://doi.org/10.31349/SuplRevMexFis.3.0308059

Keywords:

e e − annihilation, charmonium, electronic width, BESIII, two-photon process

Abstract

The direct production of the charmonium state χc1 in electron positron annihilation is searched by using e +e − collision data at four centerof-mass energies, 3.5080, 3.5097, 3.5104 and 3.5146 GeV collected with the BESIII detector at the BEPC-II collider. By combining the 4 data samples, the χc1 signal is observed with a significance of 5.1σ. An interference pattern between the signal process of e +e − → χc1 → γJ/ψ → γµ+µ − and the background process of e +e − → γISRJ/ψ → γISRµ +µ − is identified. This is the first observation of a C-even state produced directly in e +e − annihilation. At 68.3% confidence level, the electronic width of χc1 is determined to be Γee = (0.12+0.13 −0.08) eV.

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Published

2022-06-13

How to Cite

1.
Liu T. Production of χc1 in e +e − collision. Supl. Rev. Mex. Fis. [Internet]. 2022 Jun. 13 [cited 2022 Dec. 7];3(3):0308059 1-5. Available from: https://rmf.smf.mx/ojs/index.php/rmf-s/article/view/6252