  4U 1210-64 has been postulated to be a High-Mass X-ray Binary powered by the
Be mechanism. X-ray observations with Suzaku, the ISS Monitor of All-sky X-ray
Image (MAXI) and the Rossi X-ray Timing Explorer Proportional Counter Array
(PCA) and All Sky Monitor (ASM) provide detailed temporal and spectral
information on this poorly understood source. Long term ASM and MAXI
observations show distinct high and low states and the presence of a 6.7101 +/-
0.0005 day modulation, interpreted as the orbital period. Folded light curves
reveal a sharp dip, interpreted as an eclipse. To determine the nature of the
mass donor, the predicted eclipse half-angle was calculated as a function of
inclination angle for several stellar spectral types. The eclipse half-angle is
not consistent with a mass donor of spectral type B5 V; however, stars with
spectral types B0 V or B0-5 III are possible. The best-fit spectral model
consists of a power law with index gamma = 1.85 (+0.04,-0.05) and a high-energy
cutoff at 5.5 +/- 0.2 keV modified by an absorber that fully covers the source
as well as partially covering absorption. Emission lines from S XVI K alpha, Fe
K alpha, Fe XXV K alpha and Fe XXVI K alpha were observed in the Suzaku
spectra. Out-of-eclipse, Fe K alpha line flux was strongly correlated with
unabsorbed continuum flux, indicating that the Fe I emission is the result of
fluorescence of cold dense material near the compact object. The Fe I feature
is not detected during eclipse, further supporting an origin close to the
compact object.
