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.
Highlights
Hunts for fundamental correlations in strongly interacting quarks and gluons inside hadron can be a hint to understand the hadron structure and the confinement mechanism
In systems of a heavy quark and two light quarks forming a heavy baryon, thanks to asymmetry between the light quark and the heavy quark, a diquark of two light quarks could emerge in the baryon. In this brief note, taking the quark-diquark picture with a point-like diquark, we report on the excitation energy of the Λc and Λb baryons using the linear-plus-Coulomb confinement potential suitable for the quarkonium spectra
First we show the charmonium and bottonium spectra to confirm that the confinement potential with α = 0.4 and Excitation Energy [GeV]
Summary
Hunts for fundamental correlations in strongly interacting quarks and gluons inside hadron can be a hint to understand the hadron structure and the confinement mechanism. [8], the mass spectra of p and d excited states of non-strange baryons were investigated in a diquark-quark model based on the SU(6)⊗O(3) classification [9] in special attentions of the fine structure by spin-orbit interactions. In systems of a heavy quark and two light quarks forming a heavy baryon, thanks to asymmetry between the light quark and the heavy quark, a diquark of two light quarks could emerge in the baryon In this brief note, taking the quark-diquark picture with a point-like diquark, we report on the excitation energy of the Λc and Λb baryons using the linear-plus-Coulomb confinement potential suitable for the quarkonium spectra. We will find a puzzle that the string tension in the confinement potential for quark and diquark systems should be half as strong as that for quark and antiquark systems to reproduce the Λc and Λb excitation energies. These puzzles should be solved when one takes the quark-diquark picture for the heavy baryons
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
