Measurement of e + e - ? ??c0,c1,c2 cross sections at center-of-mass energies between 3.77 and 4.60 GeV
Küçük Resim Yok
Tarih
2021
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Amer Physical Soc
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
BESIII detector at BEPCII. We observe for the first time e(+)e(-)->gamma chi(c1; c2) signals at root s = 4.180 GeV with statistical significances of 7.6s and 6.0s, respectively. The production cross section of e(+)e(-)->gamma chi(c1; c2) at each center-of-mass energy is also measured. We find that the line shape of the e(+)e(-) ->gamma chi(c1) cross section can be described with conventional charmonium states psi(3686), psi(3770), psi(4040), psi(4160). Compared with this, for the e(+)e(-) ->gamma chi(c2) channel, one more additional resonance is added to describe the cross section line shape. Its mass and width are measured to be M = 4371.7 +/- 7.5 +/- 1.8 MeV=c(2) and G(tot) 1/4 =51.1 +/- 17.6 +/- 1.9 MeV, where the first uncertainties are statistical and the second systematic. The significance of this resonance is estimated to be 5.8s, and its parameters agree with the Yo4360THORN resonance previously reported in e(+)e(-)-> pi+pi(-)psi(3686), and the Y(4390) in e(+)e(-). pi(+)pi(-) h(c) within uncertainties. No significant signal for the e(+)e(-->)gamma chi(c0) process is observed, and the upper limits of Born cross sections sigma(B)(e(+)e(-)->gamma chi(c0)) at 90% confidence level are reported.
Açıklama
Anahtar Kelimeler
Kaynak
Physical Review D
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
104
Sayı
9