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The nearby barred spiral galaxy NGC 1313 has been observed with the PSPCinstr- ument on board the ROSAT X-ray satellite. Ten individual sources arefound. Three sources (X-1, X-2 and X-3 [SN~1978K]) are very bright (~10^40erg/s) and are unusual in that analogous objects do not exist in our Galaxy. Wepresent an X-ray image of NGC~1313 and \xray spectra for the three brightsources. The emission from the nuclear region (R ~< 2 kpc) is dominated bysource X-1, which is located ~1 kpc north of the photometric (and dynamical)center of NGC~1313. Optical, far-infrared and radio images do not indicate thepresence of an active galactic nucleus at that position; however, the compactnature of the \xray source (X-1) suggests that it is an accretion-poweredobject with central mass M >~ 10^3 Msun. Additional emission (L_X ~ 10^39erg/s) in the nuclear region extends out to ~2.6 kpc and roughly follows thespiral arms. This emission is from 4 sources with luminosity of several x 10^38erg/s, two of which are consistent with emission from population I sources(e.g., supernova remnants, and hot interstellar gas which has been heated bysupernova remnants). The other two sources could be emission from population IIsources (e.g., low-mass \xray binaries). The bright sources X-2 and SN~1978Kare positioned in the southern disk of NGC~1313. X-2 is variable and has nooptical counterpart brighter than 20.8 mag (V-band). It is likely that it is anaccretion-powered object in NGC~1313. The type-II supernova SN~1978K (Ryder\etal 1993) has become extra- ordinarily luminous in X-rays $\sim$13 yearsafter optical maximum.Comment: to appear in 10 Jun 1995 ApJ, 30 pgs uuencoded compressed postscript,  25 pgs of figures available upon request from colbert, whole preprint  available upon request from Sandy Shrader (shrader@lheavx.gsfc.nasa.gov),  hopefully fixed unknown problem with postscript fil

Soft X-Ray Emission from the Spiral Galaxy NGC 1313