Charged pion spectra measured in 58Ni-58Ni collisions at 1.06, 1.45 and 1.93 AGeV are interpreted in terms of a thermal model including the decay of Δ resonances. The transverse momentum spectra of pions are well reproduced by adding the pions originating from the Δ -resonance decay to the component of thermal pions, deduced from the high transverse momentum part of the pion spectra. About 10 and 18% of the nucleons are excited to Δ states at freeze-out for beam energies of 1 and 2 AGeV, respectively.
|Number of pages||6|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 1997 Aug 28|
- Thermal model
ASJC Scopus subject areas
- Nuclear and High Energy Physics