${\rm Y}$ absorption in hadronic matter

Abstract

The cross sections of ${\rm Y}$ absorption by $\pi$ and $\rho$ mesons are evaluated in a meson-exchange model. Including form factors with a cutoff parameter of 1 or 2 GeV, we find that due to the large threshold of these reactions the thermal average of their cross sections is only about 0.2 mb at a temperature of 150 MeV. Our results thus suggest that the absorption of directly produced ${\rm Y}$ by hadronic comovers in high energy heavy ion collisions is unimportant.

Comments: 11 pages, revtex, 3 figures, added references and discussion on higher BBbar states