2004IAUC.8390....1P

D. Pooley and W. H. G. Lewin, Massachusetts Institute of Technology, on behalf of a larger collaboration, report the detection of x-ray emission from the type-IIP supernova 2004dj (IAUC 8377, 8378, 8379) with the Chandra X-ray Observatory: "A 40900-s ACIS-S3 observation on Aug. 9.3 UT revealed a source at R.A. = 7h37m17s.05, Decl. = +65o35'57".9 (equinox 2000.0; ± 0".5 in each coordinate), in agreement with the reported optical and radio positions. Five hundred x-ray photons were detected, and preliminary spectral fits (using a MEKAL warm-plasma model) indicate a temperature of kT = 7 keV with a fitted column density of N_H = 6.6 x 10**20 cm**-2. The unabsorbed 0.5- to 8-keV luminosity calculated from the model is 1.5 x 10**38 erg/s (for a distance of 3.2 Mpc). This x-ray luminosity is about three times that of the type-IIP SN 1999em and nearly fifteen times that of the type-IIP SN 1999gi at similar epochs. A previous Chandra observation of NGC 2403 on 2001 Apr. 17 showed no x-ray emission near the position of SN 2004dj, with a limiting luminosity of approximately 10**36 erg/s. We encourage continued monitoring at all wavelengths. We plan to observe this source again with Chandra around Aug. 20, Oct. 1, and 2005 Jan. 15."