Look inside charmed-strange baryons from lattice QCD

Abstract

The electromagnetic form factors of the spin-3/2 Ω baryons, namely Ω, Ω * c , Ω * cc and Ωccc, are calculated in full QCD on 32 3 × 64 PACS-CS lattices with a pion mass of 156(9) MeV. The electric charge radii and magnetic moments from the E0 and M 1 multipole form factors are extracted. Results for the electric quadrupole form factors, E2, are also given. Quark sector contributions are computed individually for each observable and then combined to obtain the baryon properties. We find that the charm quark contributions are systematically smaller than the strange-quark contributions in the case of the charge radii and magnetic moments. E2 moments of the Ω * cc and Ωccc provide a statistically significant data to conclude that their electric charge distributions are deformed to an oblate shape. Properties of the spin-1/2 Ωc and Ωcc baryons are also computed and a thorough comparison is given. This complete study gives valuable hints about the heavy-quark dynamics in charmed hadrons.

Radiative transitions of doubly charmed baryons in lattice QCD

“…We have been unable to reproduce the experimental Ω mass in our previous studies with κ s = 0.13640 as tuned by the PACS-CS Collaboration to physical strange quark mass with respect to the mass of Ω baryon. Our determination of the mass of Ω on the κ sea ud = 0.13781 ensemble with κ val s = 0.13640 is m Ω = 1.790 (17) GeV, which overestimates the experimental value by ∼ 6% [43]. It is, however, in agreement with the PACS-CS value reported from the same ensemble, m Ω = 1.772 (7) GeV [39].…”

“…Previously, we have calculated magnetic moments and charge radii of charmed baryons on a wide range of pion masses changing from m π ∼ 156 MeV to m π ∼ 700 MeV [41,43,51]. We argue in Ref.…”

Charmed baryons circa 2015

“…A new lattice calculation of Ω ( * ) cc and Ω ccc was available in Ref. [67]. The various lattice results are consistent with each other and they fall into the ranges Although lattice studies suggest that the mass of the low-lying Ξ cc exceeds 3519 MeV, it is interesting to note that the authors of [51] …”

Excited state mass spectra of singly charmed baryons

“…Various phenomenological models have been used to study heavy baryons by different approaches, starting from non-relativistic Isgur-Karl model [19], then, relativized potential quark model [20], relativistic quark model [21], variational approach [22], the Fadeev approach [23], the algebraic approach [24], the Goldstone Boson Exchange Model [25], the Bonn model and Bethe-Salpter approach [26], the interacting quark-diquark model [27], the Feynman-Hellmann theorem [28], the Hypercentral Model [29], the combined expansion in 1/m Q and 1/N c [30], QCD sum rules [31], a soliton model [32], chiral quark model [33] and many more have been studied thenceforth. There are also many Lattice QCD studies which has examined the internal structure and quark dynamics of hadrons [34,35,36,37,38]. An interesting and brief description of some models are given in M.M.…”