The X-Ray Forest: A New Prediction of Hierarchical Structure Formation Models

Details The X-Ray Forest: A New Prediction of Hierarchical Structure Formation Models The X-Ray Forest: A New Prediction of Hierarchical Structure Formation Models

1998-04-03

arxiv.org/abs/astro-ph/9804038v2

Astronomy and Astrophysics

Astrophysics

Accepted by ApJ. The full resolution color GIF version of Fig.2 is included

Scientific paper

10.1086/306499

We use numerical simulations of structure formation in a Cold Dark Matter model to predict the absorption lines in the soft X-rays produced by heavy elements in the shock-heated intergalactic medium at low redshift. The simulation incorporates a model for metal production in galaxies and the subsequent dispersion of the metals to the intergalactic medium. We analyze in particular absorption lines produced by oxygen, and calculate the ionization stage taking into account the observed X-ray background at the present time. We find that oxygen is fully ionized by the X-ray background in low-density voids, and is mostly in the form of OVII and OVIII in the sheets and filamentary regions. Strong absorption lines of OVII and OVIII with equivalent widths W ~ 100 km/s are produced in filamentary regions of overdensities ~ 100 and temperatures ~ 10^6 K, located in the outskirts of groups and clusters of galaxies. The OVII line at E = 574 eV is generally the strongest one in these systems. Our model predicts that any X-ray source (such as a quasar) should typically show about one OVII absorption line with W > 100 km/s in the interval from z=0 to z=0.3. These lines could be detected with the upcoming generation of X-ray telescopes, and their origin in intervening systems could be confirmed by the association with groups of galaxies and X-ray emitting halos near the line-of-sight at the same redshift. The hot intergalactic medium may be one of the main reservoirs of baryons in the present universe, and the heavy element X-ray absorption lines offer a promising possibility of detecting this new component in the near future.

Affiliated with

Also associated with

No associations

Rating

The X-Ray Forest: A New Prediction of Hierarchical Structure Formation Models 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 The X-Ray Forest: A New Prediction of Hierarchical Structure Formation Models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The X-Ray Forest: A New Prediction of Hierarchical Structure Formation Models will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-348257