Mon. Not. R. Astron. Soc., 348, 159-164 (2004/February-2)
An X-ray absorption analysis of the high-velocity system in NGC 1275.
GILLMON K., SANDERS J.S. and FABIAN A.C.
Abstract (from CDS):
We present an X-ray absorption analysis of the high-velocity system (HVS) in NGC 1275 using results from a deep 200-ks Chandra observation. We are able to describe the morphology of the HVS in more detail than ever before. We present a Hubble Space Telescope image for comparison, and note close correspondence between the deepest X-ray absorption and the optical absorption. A column density map of the HVS shows an average column density NHof 1x1021/cm2 with a range from ∼5x1020 to 5x1021/cm2. From the NHmap we calculate a total mass for the absorbing gas in the HVS of (1.32±0.05)x109 M☉at solar abundance. 75 per cent of the absorbing mass is contained in the four regions of deepest absorption. We examine temperature maps produced by spectral fitting and find no direct evidence for shocked gas in the HVS. Using deprojection methods and the depth of the observed absorption, we are able to put a lower limit on the distance of the HVS from the nucleus of 57 kpc, showing that the HVS is quite separate from the body of NGC 1275.