The Be/X-ray and Supergiant binary systems represent the largest
sub-class of massive X-ray binaries. Of the 42 proposed massive X-ray
binary pulsar systems, 35 are identified as such binaries. The orbit
of the Be or supergiant star and the compact object, presumably a
neutron star, is generally wide and eccentric. The optical star
exhibits H
line emission and continuum free-free emission
(revealed as excess flux in the IR) from a circumstellar gas, most
likely in a disk geometry.
Progress towards a better understanding of the physics of these systems depends on a multi-wavelength programme of observations. From observations of the Be star in the optical and IR, the physical conditions under which the neutron star is accreting matter can be determined. In combination with hard X-ray timing and flux observations, this yields a near complete picture of the accretion process.
As part of such a campaign, observations have been carried out of southern hemisphere objects using the SAAO 1.9 m telescope. The individual sources have been observed as frequently as possible in order to explore both their individual IR variability and the link with the X-ray flux. Presented in this paper are the first IR observations of many proposed, and established HMXRB systems together with observations of a small number of sources with only one or two previously published values.