AAS 198th Meeting, June 2001
Session 9. Dwarf, Irregular and Starburst Galaxies
Display, Monday, June 4, 2001, 9:20am-6:30pm, Exhibit Hall

[Previous] | [Session 9] | [Next]


[9.06] Superluminal Point Sources and the Effects of Absorption on the Global X-ray Properties of the Starburst Galaxy NGC 253

K.A. Weaver (NASA/Goddard Space Flight Center), D.K. Strickland, T.M. Heckman (Johns Hopkins University)

At a distance of only 3 Mpc, NGC 253 is the brightest, closest and one of the best-studied starburst galaxies. High-quality Chandra images show that much of the X-ray emission in the disk is truly point-like, making up greater than 70% of the emission between 2 and 10 keV. At least 47 distinct, non-nuclear point sources are detected in or near the plane of the galaxy. Their distribution allows us to map out the absorption in the disk and we confirm the presence of significant absorption in the galaxy, ranging up to at least 3x1022 cm-2. This absorption was hinted at but effectively ``hidden'' in observations with Rosat and ASCA due to the limited ability to spatially resolve these components. Six of the point sources are Super-luminous, with luminosities at least 10 times larger than expected for the Eddington Limit of a ~1 solar mass accreting object (~1.3x1038 ergs s-1). Chandra is providing growing evidence that these superluminal sources occur more often in galaxies undergoing violent bursts of star formation.


The author(s) of this abstract have provided an email address for comments about the abstract: kweaver@cleo.gsfc.nasa.gov

[Previous] | [Session 9] | [Next]