Thermodynamics of Δ resonances
Abstract
The thermodynamic potential of a system of pions and nucleons is computed including the πN interactions in the P33 channel. A consistent treatment of the width of the resonance in this channel, the Δ(1232) resonance, is explored in detail. In the low-density limit we recover the leading term of the virial expansion for the thermodynamic potential. An instructive diagrammatic interpretation of the contributions to the total baryon number is presented. Furthermore, we examine within a fireball model the consequences for the pion spectra in heavy-ion collisions at intermediate energies, including the effect of collective flow. A consistent treatment of the Δ width leads to a substantial enhancement of the pion yield at low momenta.
- Publication:
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Physics Letters B
- Pub Date:
- August 1998
- DOI:
- 10.1016/S0370-2693(98)00639-X
- arXiv:
- arXiv:nucl-th/9710014
- Bibcode:
- 1998PhLB..433..236W
- Keywords:
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- Nuclear Theory;
- High Energy Physics - Phenomenology
- E-Print:
- 12 pages, 3 Postscript figures, LaTeX, elsart, epsfig, minor changes, references added, to be published in Physics Letters B