Masses of heavy baryons in the relativistic quark model

Abstract

The masses of the ground state heavy baryons consisting of two light (u,d,s) and one heavy (c,b) quarks are calculated in the heavy-quark--light-diquark approximation within the constituent quark model. The light quarks, forming the diquark, and the light diquark in the baryon are treated completely relativistically. The expansion in v/c up to the second order is used only for the heavy (b and c) quarks. The diquark-gluon interaction is taken modified by the form factor describing the light diquark structure in terms of the diquark wave functions. An overall reasonable agreement of the obtained predictions with available experimental data and previous theoretical results is found.Comment: 13 pages, 2 figures, version published in Phys. Rev.

Semileptonic decays of heavy baryons in the relativistic quark model

“…The main aim of this paper is to determine the corresponding Isgur-Wise functions in the whole kinematic range through the overlap integrals of the heavy baryon wave functions in a consistent way within the relativistic quark model. These wave functions are known from the previous calculation of baryon masses [6]. On this basis exclusive semileptonic decay rates and different asymmetries can then be evaluated within the heavy quark expansion.…”

“…Such approximation allows to reduce the very complicated relativistic three-body problem to the two-body one. Recently, we evaluated the masses of the ground state heavy baryons in the framework of the relativistic quark model based on the quasipotential approach [6]. The heavy-quark-light-diquark picture of the heavy baryons was assumed.…”

StrongΛbNBandΛcNDvertices

“…This progress has stimulated theoretical interest on the spectroscopy of these baryons via various methods (for some of them see [1][2][3][4][5][6][7][8][9][10][11] and references therein). For a better understanding of the heavy flavor physics, it is also necessary to gain deeper insight into the radiative, strong, and weak decays of the baryons containing a heavy quark.…”

Measurement of the properties of the Ξ b ∗ 0 baryon

“…Theoretical estimates of the properties of these states are available (see, e.g., refs. [1][2][3][4][5][6][7][8][9][10][11][12]). There are five known Ξ b states which, in the constituent quark model, correspond to five of the six low-lying states that are neither radially nor orbitally excited: one isodoublet of weakly-decaying ground states (Ξ 0 b and Ξ − b ) with J P = 1 2 + , one isodoublet (Ξ 0 b and Ξ − b ) with J P = 1 2 + but different symmetry properties from the ground states, and one isodoublet (Ξ * 0 b and Ξ * − b ) with J P = 3 2 + .…”