Study of the resonance structures in the process e+ e- ? ?+ ?- J/?

Küçük Resim Yok

Tarih

2022

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Amer Physical Soc

Erişim Hakkı

info:eu-repo/semantics/openAccess

Özet

Using about 23 fb(-1) of data collected with the BESIII detector operating at the BEPCII storage ring, a precise measurement of the e(+) e(-) -> pi(+) pi(-) J/psi Born cross section is performed at center-of-mass energies from 3.7730 to 4.7008 GeV. Two structures, identified as the Y(4220) and the Y(4320) states, are observed in the energy-dependent cross section with a significance larger than 10 sigma. The masses and widths of the two structures are determined to be (M,(sic)) = (4221.4 +/- 1.5 +/- 2.0 MeV=c(2); 41.8 +/- 2.9 +/- 2.7 MeV) and (M,(sic)) = (4298 +/- 12 +/- 26 MeV=c(2); 127 +/- 17 +/- 10 MeV)respectively. A small enhancement around 4.5 GeV with a significance about 3s, compatible with the psi(4415), might also indicate the presence of an additional resonance in the spectrum. The inclusion of this additional contribution in the fit to the cross section affects the resonance parameters of the Y(4320) state.

Açıklama

Anahtar Kelimeler

Monte-Carlo Simulation, Charmonium

Kaynak

Physical Review D

WoS Q Değeri

Q1

Scopus Q Değeri

Q1

Cilt

106

Sayı

7

Künye