  We present a measurement of the polarization observed for bottomonium states
produced in p-Cu collisions at sqrt(s)=38.8 GeV. The angular distribution of
the decay dimuons of the Upsilon(1S) state show no polarization at small xF and
pT but significant positive transverse production polarization for either pT >
1.8 GeV/c or for xF > 0.35. The Upsilon(2S+3S) unresolved states show a large
transverse production polarization at all values of xF and pT measured. These
observations are compared with an NRQCD calculation that predicts a transverse
polarization in bottomonium production arising from quark-antiquark fusion and
gluon-gluon fusion diagrams.
