Lowest-lying spin-1/2 and spin-3/2 baryon magnetic moments in chiral perturbation theory

We review some recent progress in our understanding of the lowest-lying spin-1/2 and spin-3/2 baryon magnetic moments （MMs） in terms of Chiral Perturbation Theory （ChPT）.In particular,we show that at next-to-leading-order ChPT can describe the MMs of the octet baryons quite well.We also make predictions for the decuplet MMs at the same chiral order.Among them,the MMs of the Δ＋＋ and Δ ＋ are found to agree well with data within the experimental uncertainties.     

Spectrum of b-baryons:color hyperfine interaction vs. experiment

I discuss several recent highly accurate theoretical predictions for masses of baryons containing the b quark, especially Ωb (ssb) very recently reported by CDF. I also point out an approximate effective supersymmetry between heavy quark baryons and mesons and provide predictions for the magnetic moments of Λc and Λb. Proper treatment of the color-magnetic hyperfine interaction in QCD is crucial for obtaining these results.     

Lowest-lying spin-1/2 and spin-3/2 baryon magnetic moments in chiral perturbation theory

We review some recent progress in our understanding of the lowest-lying spin-1/2 and spin-3/2 baryon magnetic moments (MMs) in terms of Chiral Perturbation Theory (ChPT).In particular,we show that at next-to-leading-order ChPT can describe the MMs of the octet baryons quite well.We also make predictions for the decuplet MMs at the same chiral order.Among them,the MMs of the Δ++ and Δ + are found to agree well with data within the experimental uncertainties.     

Spectroscopy of the Ωccb baryon in the hypercentral constituent quark model

We extract the mass spectrum of the triply heavy baryon Ω_ccb using the hypercentral constituent quark model. The first order correction is also added to the potential term of the Hamiltonian. The radial and orbital excited state masses are determined, and the Regge trajectories and magnetic moments for this baryon are also given.     

Diquark structure in heavy quark baryons in a geometric model

Using a geometric model to study the structure of hadrons, baryons having one, two and three heavy quarks have been studied here. The study reveals diquark structure in baryons with one and two heavy quarks but not with three heavy identical quarks.     

Analysis of (1/2)~+ baryon states containing fourth-family quarks from QCD sum rules

When the fourth generation of quarks have sufficiently small mixing with ordinary standard-model quarks, the hadrons made up from these quarks can be long-lived enough. We analyze the (1/2)⁺ baryon states containing fourth-generation quarks and standard-model quarks, i.e. the charm or bottom quarks, in the QCD sum rules approach. Considering the perturbative and two gluon condensate contributions in the calculation, we give the numerical results of the masses and pole residues.     

Electromagnetic transition properties of→Nγ in a hypercentral scheme

The electromagnetic transition properties of the decuplet to octet baryon (→ Nγ) is studied within the framework of a hypercentral quark model.The confinement potential is assumed as a hypercentral coloumb plus linear potential.The transition magnetic moment and transition amplitude f M 1 for the → Nγ are in agreement with other theoretical predictions.The present result of the radiative decay width is found to be in excellent agreement with the experimental values reported by the particle data group over other theoretical model predictions.     

Quark-diquark model description for double charm baryons

We report here the mass spectrum and magnetic moments of ccq（q ∈ u,d,s） systems in the potential model framework by assuming the inter-quark potential as the colour coulomb plus power form with power index ν varying between 0.1 to 2.0.Here the two charm quarks are considered for the diquark states.The conventional one gluon exchange interaction has been employed to get the hyperfine and the fine structure between different states.We have predicted many low-lying states whose experimental verification can exclusively support the quark-diquark structure of the baryons.     

Extraction of radiative decay width for the non-strange partner of Θ

Using the results of the GRAAL Collaboration on the η photoproduction from the neutron target, we attempt to extract the partial radiative width of the possible new nucleon resonance N ^*(1675). The obtained estimates support this resonance to be a very attractive candidate for the non-strange member of the exotic antidecuplet of baryons --a partner of the Θ⁺ pentaquark. Our phenomenological value for the transition magnetic moment μ(n ^* n), appears to be in good agreement with the predictions of the Chiral Quark Soliton Model.