Quark confinement potential examined by excitation energy of the Lambda_c and Lambda_b baryons in a quark-diquark model

Abstract

The possibility to have diquark configuration in heavy baryons, such as Lambda_c and Lambda_b, is examined by a nonrelativistic potential model with a heavy quark and a light scalar diquark. Assuming that the Lambda_c and Lambda_b baryons are composed of the heavy quark and the point-like scalar-isoscalar ud diquark, we solve the two-body Schrodinger equation with the Coulomb plus linear potential and obtain the energy spectra for the heavy baryons. Contrary to our expectation, it is found that the potential determined by the quarkonium spectra fails to reproduce the excitation spectra of the Lambda_c and Lambda_b in the quark-diquark picture, while the Lambda_c and Lambda_b spectra is reproduced with a half strength of the confinement string tension than for the quarkonium. The finite size effect of the diquark is also examined and it is found that introduction of a finite size diquark would resolve the failure of the spectrum reproduction. The Xi_c excitation energy is also calculated and is found to be smaller than Lambda_c in the quark-diquark model. This is not consistent with the experimental observation.

16 pages, 12 figures

References in corpus (3)

• Big-Bang Nucleosynthesis
• Evidence for diquarks in lattice QCD
• Non-perturbative Analysis of Various Mass Generation by Gluonic Dressing Effect with the Schwinger-Dyson Formalism in QCD

Cited by in corpus (12)

• Floquet Many-body Engineering: Topological and Many-body Physics in Phase Space Lattices
• Chiral effective theory of diquarks and the U_A(1) anomaly
• Spectrum of singly heavy baryons from a chiral effective theory of diquarks
• Heavy baryon spectrum with chiral multiplets of scalar and vector diquarks
• Excitation energy spectra of the Lambda_c and Lambda_b baryons in a finite-size diquark model
• Quark-diquark potential and diquark mass from Lattice QCD
• Strong decays of singly heavy baryons from a chiral effective theory of diquarks
• Sum rule for the partial decay rates of bottom hadrons based on the dynamical supersymmetry of the $\bar{s}$ quark and the $ud$ diquark
• Excitation spectra of heavy baryons in diquark models
• Systematic study of hadronic excitation energy using Schottky anomaly
• Dynamical supersymmetry for strange quark and $ud$ antidiquark in hadron mass spectrum
• Chiral effective theory of scalar and vector diquarks revisited