Speaker
Pok Man Lo
(GSI)
Description
In this talk we compare two approaches in modeling repulsive interactions
among hadrons: the excluded-volume approximation and the S-matrix formalism.
The latter provides a consistent treatment of broad resonances based on
empirical scattering phase shifts. We shall apply these techniques to study
the thermodynamics of the (πN∆) system, with a particular focus on the
fluctuation of Baryon charge in the thermal medium.
We show that the introduction of an excluded volume between pions and
nucleons, in addition to the interaction that generates the $\Delta$
resonance, distorts the phase shift in the $P_{33}$ channel and hence
leads to an inconsistent description of the interaction contribution
to the thermodynamics.
Author
Pok Man Lo
(GSI)
