Evidence for a neutral near-threshold structure in the K S0 recoil-mass spectra in e+e- ? K S0 Ds+ D?- and e+e- ? K S0 Ds?+ D-

Yükleniyor...
Küçük Resim

Tarih

2022

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

American Physical Society

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

We study the processes e+e-?KS0Ds+D?- and e+e-?KS0Ds?+D-, as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8 fb-1 collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for Ds+D?- and Ds?+D- production in the KS0 recoil-mass spectrum, which we refer to as the Zcs(3985)0. Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6) MeV/c2 and the width to be (7.7-3.8+4.1±4.3) MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Zcs(3985)0 signal is found to be 4.6? including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Zcs(3985)0 is close to that of the Zcs(3985)+. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Zcs(3985)0 is the isospin partner of the Zcs(3985)+.

Açıklama

Anahtar Kelimeler

Kaynak

Physical Review Letters

WoS Q Değeri

Q1

Scopus Q Değeri

N/A

Cilt

129

Sayı

11

Künye

Ablikim, M., Achasov, M. N., Adlarson, P., Albrecht, M., Aliberti, R., Amoroso, A., . . . (BESIII Collaboration). (2022). Evidence for a neutral near-threshold structure in the K S0 recoil-mass spectra in e+e- → K S0 ds+ D∗- and e+e- → K S0 ds∗+ D-. Physical Review Letters, 129(11) doi:10.1103/PhysRevLett.129.112003