X-ray Dust Halos Seen With Extreme Dynamic Range: What Do We Learn?

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

The exquisite angular resolution available with Chandra should allow precision measurements of faint diffuse emission surrounding bright sources, such as the X-ray scattering halos created by interstellar dust. However, the ACIS CCDs suffer from pileup when observing bright sources, and this creates difficulties when trying to extract the scattered halo near the source. The initial study of the X-ray halo around GX13+1 using only the ACIS-I detector done by Smith, Edgar & Shafer (2002) suffered from a lack of sensitivity within 50'' of the source, limiting what conclusions could be drawn.
To address this problem, observations of GX13+1 were obtained with the Chandra HRC-I and simultaneously with the RXTE PCA. Combined with the existing ACIS-I data, this allowed measurements of the X-ray halo between 2-1000''. After considering a range of dust models, each assumed to be smoothly distributed with or without a dense cloud along the line of sight, the results show that there is no evidence in this data for a dense cloud near the source, as suggested by Xiang et al. 2005. Finally, although no model leads to formally acceptable results, the Weingartner & Draine (2001) and nearly all of the composite grain models from Zubko, Dwek & Arendt (2004) give poor fits.
I thank Dr. Michael Juda of the HRC-I team for providing significant assistance; this work was supported by Chandra Observing Grant GO56144X.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

X-ray Dust Halos Seen With Extreme Dynamic Range: What Do We Learn? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with X-ray Dust Halos Seen With Extreme Dynamic Range: What Do We Learn?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and X-ray Dust Halos Seen With Extreme Dynamic Range: What Do We Learn? will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-765560

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.