OAO1657-415 is only the seventh eclipsing X-ray pulsar known and therefore
has the potential to yield only the seventh mass of a neutron star in an X-ray
binary. Here we report photometric and spectroscopic observations of candidates
for the optical counterpart to the system and identify a B6V or B5III star as a
possible companion to the neutron star. We measure the observational parameters
of the star and suggest reasons why OAO1657-415 may be unlike other high mass
X-ray binaries.Comment: 5 pages, 5 figures, to be published in 'Evolution of binary and
multiple star systems', proceedings of conference, Bormi
