arXiv subjects
Publications and source records attributed to Andrius Bernotas.
We study the M1 transitions of ground state heavy baryons within a framework of the modified bag model. Calculations of transition moments and corresponding M1 decay widths are performed. For the spin 1/2 baryons containing three differently flavoured quarks the hyperfine mixing effects are taken into account. Results are compared with estimates obtained using various other approaches.
Magnetic moments of J = 1/2 and J = 3/2 heavy baryons are calculated in the bag model with center-of-mass motion corrections. For the spin 1/2 baryons containing three quarks of different flavours the effect of hyperfine mixing is examined in detail. The results of the work are compared with predictions obtained in various other approaches and models.
The dependence of light hadron masses and baryon magnetic moments on the magnitude of the Casimir energy is examined in the bag model with center-of-mass corrections. There are seven free parameters in the model. Six of them are determined from the fit to the masses of certain hadrons, and the last one (Casimir energy parameter) from the best fit to the magnetic moments of light baryons. The predicted magnetic moments are compared with the results obtained in various other models and with experiment data.
Some time ago a slightly improved variant of bag model (the modified bag model) suitable for the unified description of light and heavy hadrons was developed. The main goal of the present work was to calculate the masses of the ground state baryons containing bottom quarks in the framework of this model. For completeness the predictions for other heavy hadrons are also given. The reasonable agreement of our results with other theoretical calculations and available experimental data suggests that our predictions could serve as a useful complementary tool for the interpretation of heavy hadron spectra.
Spin-spin interaction causes the mixing between ground state wave functions of baryons containing three quarks of different flavors. We examine the effect of this mixing on the baryon masses in the framework of the modified bag model.
Mass spectra of ground state hadrons containing u-, d-, s-, c-quarks as well as some lightest hadrons containing b-quarks are calculated on the basis of a slightly modified bag model. The center-of-mass motion corrections are incorporated using a wavepacket projection with Gaussian parametrization of the distribution amplitude. We use running coupling constant and also allow the effective quark mass to be scale-dependent. The impact of these modifications on the hadron mass spectrum is investigated. A comparison of the predicted mass values with the experimental data demonstrates that the modified bag model is sufficiently flexible to provide a satisfactory description of light and heavy hadrons (mesons and baryons) in a single consistent framework.
Concentration of the strongest transitions on the high-energy side of some emission, photoexcitation and Auger spectra of atoms is related with the existence of the additional selection rule for the number of vacancy-electron pairs.