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V. Magas

Publications and source records attributed to V. Magas.

8 recordsLinked to original sources
arXiv2008

Chiral SU(3) Bethe Salpeter Model: Extension to SU(6) and SU(8) Spin-Flavor Symmetries

Consistent SU(6) and SU(8) spin-flavor extensions of the SU(3) flavor Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian are constructed, which incorporate vector meson degrees of freedom. In the charmless sector, the on-shell approximation to the Bethe-Salpeter (BS) approach successfully reproduces previous SU(3) WT results for the lowest-lying s--wave negative parity baryon resonances. It also provides some information on the dynamics of heavier ones and of the lightest d-wave negative parity resonances, as e.g. the Lambda(1520). For charmed baryons the scheme is consistent with heavy quark symmetry, and our preliminary results in the strangeness-less charm C=+1 sector describe the main features of the three-star J^P=1/2^- Lambda_c(2595) and J^P=3/2^- Lambda_c(2625) resonances. We also find a second broad J^P=1/2^- state close to the Lambda_c(2595)

hep-ph↗
arXiv2003

Conditions for Confinement and Freeze-Out

Matter implies the existence of a large-scale connected cluster of a uniform nature. The appearance of such clusters as function of hadron density is specified by percolation theory. We can therefore formulate the freeze-out of interacting hadronic matter in terms of the percolation of hadronic clusters. The resulting freeze-out condition as function of temperature and baryo-chemical potential interpolates between resonance gas behaviour at low baryon density and repulsive nucleonic matter at low temperature, and it agrees well with data.

hep-ph↗
arXiv2002

Statistical Hadronization of Supercooled Quark-Gluon Plasma

The fast simultaneous hadronization and chemical freeze out of supercooled quark-gluon plasma, created in relativistic heavy ion collisions, leads to the re-heating of the expanding matter and to the change in a collective flow profile. We use the assumption of statistical nature of the hadronization process, and study quantitatively the freeze out in the framework of hydrodynamical Bjorken model with different quark-gluon plasma equations of state.

nucl-th↗
arXiv2002

From Regge Behavior to DGLAP Evolution

We study the interface between Regge behavior and DGLAP evolution in a non-perturbative model for the nucleon structure function based on a multipole pomeron exchange. This model provides the input for a subsequent DGLAP evolution that we calculate numerically. The soft input and its evolution give a good fit to the experimental data in the whole available range of x and Q^2.

hep-ph↗
arXiv2000

Analytic model of Regge trajectories

A model for a Regge trajectory compatible with the threshold behavior required by unitarity and asymptotics in agreement with analyticity constraints is given in explicit form. The model is confronted in the time-like region with widths and masses of the mesonic resonances and, in the space-like region, the $ρ$ trajectory is compared with predictions derived from $π-N$ charge-exchange reaction. Breaking of the exchange degeneracy is studied in the model and its effect on both the masses and widths is determined.

hep-ph↗
arXiv1999

Analytic Model of a Regge Trajectory in the Space-like and Time-like Regions

A model for a Regge trajectory compatible with the threshold behavior required by unitarity and asymptotics in agreement with Mandelstam analyticity is analyzed and confronted with the experimental data on the spectrum of the $ρ$ trajectory as well as those on the $π^- p\to π^0 n$ charge-exchange reaction. The fitted trajectory deviates considerably from a linear one both in the space-like and time-like regions, matching nicely between the two.

hep-ph↗
arXiv1999

Freeze out in hydrodynamical models

We study the effects of strict conservation laws and the problem of negative contributions to final momentum distribution during the freeze out through 3-dimensional hypersurfaces with space-like normal. We study some suggested solutions for this problem, and demonstrate it on one example.

nucl-th↗