Quantum numbers of Ωc states and other charmed baryons

Hai-Yang Cheng and Cheng-Wei Chiang
Phys. Rev. D 95, 094018 – Published 25 May 2017

Abstract

Possible spin-parity quantum numbers for excited charmed baryon resonances are discussed in this work. Our main results are as follows. (i) Among the five newly observed Ωc states, we have identified Ωc(3090) and Ωc(3119) with radially excited 12+(2S) and 32+(2S) states, respectively, and Ωc(3000) with 12(1P). The two states Ωc(3050) and Ωc(3066) form a P-wave (32,52) doublet. (ii) The widths of Ωc(3066) and Ξc(2930) are calculable within the framework of heavy hadron chiral perturbation theory. (iii) Since the width of Ωc0(12) is of order 410 MeV, not all observed narrow Ωc baryons can be identified with 1P states. (iv) For the antitriplet Λc and Ξc states, their Regge trajectories for the orbital excitations of 12 and 32 are parallel to each other. Based on this nice property of parallelism, we see that the highest state Λc(2940) does not fit if its quantum numbers are 32 as found by LHCb. We suggest that Λc(2940)+ is most likely the 12(2P) state. (v) The charmed baryon Σc(2800) cannot be a 12 state; otherwise, its width will be over 400 MeV, too large compared to the measured one. (vi) In the study of Regge trajectories of Ξc states, we find a missing state. It should have quantum numbers 52 with a mass around 2920 MeV. (vii) Antitriplet and sextet states are classified according to their JP(nL) quantum numbers. The mass differences between Ξc and Λc in the antitriplet states clearly lie between 180 and 200 MeV. Moreover, the mass splitting between Ωc and Ξc is found to be very close to the one between Ξc and Σc for five different sets of sextet multiplets. This lends a strong support to the quantum number assignment to the sextet states in this work.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 5 April 2017

DOI:https://doi.org/10.1103/PhysRevD.95.094018

© 2017 American Physical Society

Physics Subject Headings (PhySH)

  1. Physical Systems
Particles & Fields

Authors & Affiliations

Hai-Yang Cheng1 and Cheng-Wei Chiang1,2,3

  • 1Institute of Physics, Academia Sinica, Taipei 11529, Taiwan, Republic of China
  • 2Department of Physics, National Taiwan University, Taipei 10617, Taiwan, Republic of China
  • 3Physics Division, National Center for Theoretical Sciences, Hsinchu 30013, Taiwan, Republic of China

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 95, Iss. 9 — 1 May 2017

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review D

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×