Mapping the Hot Gas in the Galaxy with XMM-Newton

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

The Galaxy is permeated by gas with a temperature between 1 and 3 million K. This X-ray-emissive gas makes a significant contribution to the diffuse soft X-ray background (SXRB), particularly at high Galactic latitudes. By measuring the spectrum of the SXRB emission, we can determine the physical conditions in the hot gas, and thereby constrain its origin and evolution.
We present results from a survey of the SXRB that we are carrying out using archival XMM-Newton observations. We do not restrict ourselves to blank-sky observations, but instead use as many observations as possible, removing bright or extended sources by hand if necessary. We present measurements of the SXRB O VII and O VIII intensities extracted from several hundred XMM-Newton observations. The variation of these intensities over the sky helps constrain the distribution of hot gas in the Galaxy, while for directions with multiple observations, the time variation of the intensities can be used to constrain models of solar wind charge exchange (SWCX) emission. In addition, we present measurements of the Galactic halo temperature and emission measures extracted from a subset of our observations. These observations were chosen as they are expected to have the smallest levels of SWCX contamination. By comparing these measurements with the predictions of hydrodynamical models, we can strongly rule out a model in which the hot halo gas seen with XMM-Newton resides in isolated extraplanar supernova remnants. Instead, we find that the halo X-ray surface brightness above 0.4 keV is likely dominated by emission from a supernova-driven galactic fountain, although we cannot rule out the possibility that an extended halo of accreted material also contributes.
This work is supported by NASA grant NNX08AJ47G, awarded through the Astrophysics Data Analysis Program.

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

Mapping the Hot Gas in the Galaxy with XMM-Newton 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 Mapping the Hot Gas in the Galaxy with XMM-Newton, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mapping the Hot Gas in the Galaxy with XMM-Newton will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1396846

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