Győző Kovács, Péter Kovács, György Wolf (2023.01.01 - 11.30)

Wigner Research Centre for Physics

Grant: NKFIH FK 131982

Publication: Phenomenology of isospin-symmetry breaking with vector mesons

Abstract: The extended linear sigma model (eLSM) is an advanced quarkmeson model that can be used to study meson phenomenology at zero temperature and the QCD phase diagram at finite temperature and/or baryon chemical potential. In order to make predictions, parameters of the model should be determined by fitting calculated physical quantities (like masses and decay widths) to their experimental values. The best fit and global minimum can be found by choosing some random starting points in the k-dimensional parameter space (in our case \(k > 14\)) and run a \(\chi^2\) multiparametric minimization. This procedure is numerically quite expensive and time-consuming. However, a large number of starting points (\(n ∼ 10^7\) ) is required to achieve a reasonable statistics and resolution in the parameter values. In order to gain a good understanding of the model, its parameter dependence, and parameterization, it is also necessary to perform the fitting also under variation of the physical quantities involved.