X-RAY-EMISSION FROM M32 - X-RAY BINARIES OR A MU-AGN

We have analyzed archival ROSATPSPC data for M32 in order to study the X-ray emission from this nearest elliptical galaxy. We fitted spectra from three long exposures with Raymond-Smith, thermal bremsstrahlung, and power-law models. All models give excellent fits. The thermal fit s have kT approximate to 4 keV, the Raymond-Smith iron abundance is 0. 4(-0.3)(+0.7) solar, the power-law fit has alpha = 1.6 +/- 0.1, and al l fits have N-H consistent with the Galactic column. The source is cen tered on M32 to an accuracy of 9 '', and unresolved at 27 '' FWHM (sim ilar to 90 pc). M32 is X-ray variable by a factor of 3-5 on timescales of a decade down to minutes, with evidence for a possible period of s imilar to 1.3 days. There are two plausible interpretations for these results: (1) emission due to low-mass X-ray binaries; (2) emission due to accretion onto a massive central black hole. Both of these possibi lities are supported by arguments based on previous studies of M32 and other old stellar systems; the ROSAT PSPC data do not allow us to una mbiguously choose between them. Observations with the ROSAT HRI and wi th ASCA are required to determine which of these two very different ph ysical models is correct.