  We use a Glauber-like approach to describe very energetic nucleus-nucleus
collisions as a sequence of binary nucleon-nucleon collisions. No free
parameters are needed: all the information comes from simple parametrizations
of nucleon-nucleon collision data. Produced mesons are assumed not to interact
with each other or with the original baryons. Comparisons are made to published
experimental measurements of baryon rapidity and transverse momentum
distributions, negative hadron rapidity and transverse momentum distributions,
average multiplicities of pions, kaons, hyperons, and antihyperons, and zero
degree energy distributions for sulfur-sulfur collisions at 200 GeV/c per
nucleon and for lead-lead collisions at 158 GeV/c per nucleon. Good agreement
is found except that the number of strange particles produced, especially
antihyperons, is too small compared with experiment. We call this model LEXUS:
it is a baseline linear extrapolation of ultrarelativistic nucleon-nucleon
scattering to heavy ion collisions.
