Large $p_t$ enhancement from freeze out

V. K. Magas, Cs. Anderlik, L. P. Csernai, F. Grassi, W. Greiner, Y. Hama, T. Kodama, Zs. Lázár, H. Stöcker

Published 1999-05-26Version 1

Freeze out of particles across three dimensional space-time hypersurface is discussed in a simple kinetic model. The final momentum distribution of emitted particles, for freeze out surfaces with space-like normal, shows a non-exponential transverse momentum spectrum. The slope parameter of the $p_t$ distribution increases with increasing $p_t$, in agreement with recently measured SPS pion and $h^-$ spectra.