SIMBAD references

D. Pooley and W. H. G. Lewin, Massachusetts Institute of Technology, report the detection of x-ray emission (154 counts) from the type-Ib/c supernova 2001em (IAUC 7722, 7737, 8282) with the Chandra x-ray observatory. A 14600-s ACIS-S3 observation on Apr. 4.81 UT revealed a source at R.A. = 21h42m23s.60, Decl. = +12o29'50".3 (equinox 2000.0; ± 0".5 in each coordinate), in close agreement with the reported optical and radio positions. Preliminary spectral fits (using either a MEKAL or power-law model) indicate a hard spectrum (MEKAL temperature above the model limit of kT = 80 keV or power-law photon index of 1.1) with a fitted column density of N_H approximately equal to 1.6 x 10**21 cm**-2. The unabsorbed 0.5-8-keV luminosity calculated from both models agrees well and is roughly 10**41 erg/s (for a distance of 80 Mpc). This high x-ray luminosity (the second highest ever reported for a young supernova) could indicate a substantial amount of circumstellar interaction. Further observations at other wavelengths are encouraged.