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M.A. Smith, R.D. Robinson (CUA), G.W. Henry (TSU)
\gamma Cas is a classical B0.5e star known to be a unique X-ray source by virtue of its moderate Lx (1033 ergs~s-1), hard X-ray spectrum, and light curve punctuated by ubiquitous flares and slow undulations. There is not a complete consensus on the origin of these emissions, whether from the Be star or from wind infall onto a putative degenerate binary companion. In the last year much progress has been made to resolve this question: (1) the discovery by Harmanec et al. (2000) that \gamma\,Cas is a moderately eccentric binary system (P = 203.6~d) with unknown secondary type, (2) the addition of RXTE observations at 6 epochs in 2000, adding to 3 others in 1996-8, (3) the collation of robotic telescope (APT) B, V-band photometric observations over 4 seasons which show a 3%, cyclical flux variation with cycle lengths of 55-85 days. We find that X-ray fluxes at all 9 epochs show random variations with orbital phase, thereby contradicting the binary accretion model. However, these fluxes correlate well with the optical variations. In particular, the six flux levels in 2000, which vary by a factor of three, closely track the interpolated optical variations between the 2000 and 20001 optical seasons. This result suggests that the optical variations originate from processing of X-rays, e.g. from modulated irradiation of the Be star's photosphere. Since the optical and X-ray variations are not strictly periodic, we suggest that their origin lies in a dynamo, either within the star or in the dense circumstellar Be disk.