We report on a study of the process e+e-→π±(DD̄*) - at s=4.26 GeV using a 525 pb-1 data sample collected with the BESIII detector at the BEPCII storage ring. A distinct charged structure is observed in the (DD̄*)- invariant mass distribution. When fitted to a mass-dependent-width Breit-Wigner line shape, the pole mass and width are determined to be M_pole = (3883.9±1.5(stat)±4.2(syst)) MeV/c2 and Γ_pole = 24.8±3.3(stat)±11.0(syst)) MeV. The mass and width of the structure, which we refer to as Zc(3885), are 2σ and 1σ, respectively, below those of the Zc(3900)→π±J/ψ peak observed by BESIII and Belle in π+π-J/ψ final states produced at the same center-of-mass energy. The angular distribution of the πZc(3885) system favors a JP=1+ quantum number assignment for the structure and disfavors 1- or 0-. The Born cross section times the DD̄* branching fraction of the Zc(3885) is measured to be σ(e+e-→π±Zc(3885)-) ×B(Zc(3885)- →(DD̄*)-)=(83.5±6.6(stat)±22. 0(syst)) pb. Assuming the Zc(3885)→DD̄* signal reported here and the Zc(3900)→πJ/ψ signal are from the same source, the partial width ratio (Γ(Zc(3885)→DD̄*)/Γ(Zc(3900)→πJ/ ψ))=6.2±1.1(stat)±2.7(syst) is determined.

Observation of a charged (DD¯∗)± mass peak in e+e−→πDD¯∗ at √s= 4.26 GeV

DESTEFANIS, MARCO GIOVANNI;GRECO, Michela;MAGGIORA, MARCO;SPATARO, STEFANO GIOVANNI;
2014-01-01

Abstract

We report on a study of the process e+e-→π±(DD̄*) - at s=4.26 GeV using a 525 pb-1 data sample collected with the BESIII detector at the BEPCII storage ring. A distinct charged structure is observed in the (DD̄*)- invariant mass distribution. When fitted to a mass-dependent-width Breit-Wigner line shape, the pole mass and width are determined to be M_pole = (3883.9±1.5(stat)±4.2(syst)) MeV/c2 and Γ_pole = 24.8±3.3(stat)±11.0(syst)) MeV. The mass and width of the structure, which we refer to as Zc(3885), are 2σ and 1σ, respectively, below those of the Zc(3900)→π±J/ψ peak observed by BESIII and Belle in π+π-J/ψ final states produced at the same center-of-mass energy. The angular distribution of the πZc(3885) system favors a JP=1+ quantum number assignment for the structure and disfavors 1- or 0-. The Born cross section times the DD̄* branching fraction of the Zc(3885) is measured to be σ(e+e-→π±Zc(3885)-) ×B(Zc(3885)- →(DD̄*)-)=(83.5±6.6(stat)±22. 0(syst)) pb. Assuming the Zc(3885)→DD̄* signal reported here and the Zc(3900)→πJ/ψ signal are from the same source, the partial width ratio (Γ(Zc(3885)→DD̄*)/Γ(Zc(3900)→πJ/ ψ))=6.2±1.1(stat)±2.7(syst) is determined.
2014
112
022001-1
022001-7
M. Ablikim; M. N. Achasov; O. Albayrak; D. J. Ambrose; F. F. An; Q. An; J. Z. Bai; R. Baldini Ferroli; Y. Ban; J. Becker; J. V. Bennett; M. Bertani; J...espandi
File in questo prodotto:
File Dimensione Formato  
PRL112.022001.arxiv.pdf

Accesso aperto

Tipo di file: PREPRINT (PRIMA BOZZA)
Dimensione 447.16 kB
Formato Adobe PDF
447.16 kB Adobe PDF Visualizza/Apri
PhysRevLett.112.022001.pdf

Accesso riservato

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 428.38 kB
Formato Adobe PDF
428.38 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/152403
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 327
  • ???jsp.display-item.citation.isi??? 268
social impact