Improved predictions for magnetic moments and M1 decay widths of heavy hadrons

Abstract

In the framework of an extended bag model the magnetic moments, M1 transition moments, and decay widths of all ground-state heavy hadrons are calculated. For the heavy baryons containing three quarks of different flavors the effect of hyperfine mixing of the states is taken into account. The additional care is taken to get more accurate theoretical estimates for the mass splittings of heavy hadrons. The use of such improved values enables one to provide more accurate predictions for the decay widths. These values of the hyperfine splittings between baryons may be also useful for the further experimental searches of new heavy hadrons. For instance, we predict M (Ξ * cc ) = 3695 ± 5 MeV. The agreement of our results for the M1 decay rates with available experimental data is good. We also present a wide comparison of the predictions obtained in our work with the results obtained using various other approaches.

Magnetic moments of spin--1/2 triply-heavy baryons: A study of Light-cone QCD and Quark-diquark model

“…For the sake of comparison we also give different models namely BD, AL1, AL2, AP1, AP2 potential models [30], hypercentral constituent quark model (HCCQM) [35], non-relativistic quark-diquark model (NRQDM) [39], power-law potential [62], relativistic logarithmic potential (RLP) [63], non-relativistic quark model (NRQM) [64], relativistic three-quark model (RTQM) [65], bag model and nonrelativistic quark model (NRQM-I) [66], effective mass (EMS) and screened charge scheme (SCS) [67] and extended bag model (EBM) [68]. -0.193 0.475 AL2 [30] -0.192 0.471 AP1 [30] -0.195 0.479 AP2 [30] -0.193 0.473 HCCQM [35] -0.203 0.502 NRQDM [39] -0.223 0.565 Power law [62] -0.197 0.476 RLP [63] -0.20 0.49 NRQM [64] -0.193 0.475 RTQM [65] -0.20 0.53 Bag model [66] -0.205 0.505 NRQM-I [66] -0.21 0.54 EMS [67] -0.205 0.508 SCS [67] -0.200 0.522 EBM [68] - It can be seen from Table III that magnetic moment of Ω 0 cbb changes from −0.19 ± 0.06 to -0.227, whereas magnetic moment of Ω + ccb changes from 0.466 to 0.61 ± 0.21 in unit of µ N , respectively. The results of the references agree well with one another.…”

Lattice QCD study of the elastic and transition form factors of charmed baryons

“…Although the origin of this evident discrepancy is still an open issue, the most plausible reason seems like the treatment of the heavy quark sector in model approaches. It has been shown that it is possible to improve the model predictions by treating the heavy and light quark sectors separately and determining the hyperfine splittings more accurately, 84 although a discrepancy remains for the doubly charmed sector. Additionally, there are indications that when the lattice data, rather than the quark model predictions, are used as input to fix some low-energy constants of effective theories their results get smaller than quark model's and closer to lattice predictions.…”

“…There are many early and recent non-lattice works available in the literature investigating the electromagnetic interactions of charmed baryons. These include variations of quark model approaches; [64][65][66][67][68][69][70][71][72][73][74][75][76][77][78][79][80] bag model; [81][82][83][84] QCD sum rules; 77,[85][86][87][88][89][90] (heavy baryon) chiral perturbation theory; [91][92][93][94][95][96][97][98][99][100] effective field theory, [101][102][103] and chiral quark-soliton model [104][105][106][107][108][109] calculations regarding the elastic and transition form factors. A striking outcome of all the lattice works …”

Angular distribution and asymmetries in the decay of the polarized charmed baryon $Λ_c^+ \to K^- \, Δ^{++} \to K^- \, p \, π^+$

“…4 Another important aspect of the study of Λ + c polarization is related to a possibility to measure its magnetic dipole moment (MDM) and electric dipole moment (EDM) using spin precession in a strong effective magnetic field inside bent crystals. [5][6][7][8][9][10] The motivation here is comparison of experiment with various theoretical calculations of the MDM (see, e.g., 11,12 and references therein). Such measurements may also provide information on the MDM of the charm quark.…”