Meson mT-scaling in heavy-ion collisions at SIS energies

We perform systematical studies on transverse-mass spectra of pi(0), eta, omega, phi, K+ and K- mesons for C + C, Ni + Ni, Au + Au collisions at SIS energies within the HSD transport approach. We find that the m(T)-spectra sensitively reflect the in-medium properties of the mesons. The 'bare mass' scenario leads to a general scaling behaviour for the meson m(T)-spectra when including a mass shift due to the associate strangeness production threshold for kaons and antikaons whereas a 'dropping' mass scheme violates this m(T)-scaling. The relative slope parameters, however, provide valuable information about the average meson potentials in the nuclear medium. (C) 1998 Published by Elsevier Science B.V.