The Cluster-Merger Shock in 1E 0657-56: Faster than a Speeding Bullet?

Details The Cluster-Merger Shock in 1E 0657-56: Faster than a Speeding Bullet? The Cluster-Merger Shock in 1E 0657-56: Faster than a Speeding Bullet?

Aug 2008

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008aspc..393..223k&link_type=abstract

New Horizons in Astronomy: Frank N. Bash Symposium 2007 ASP Conference Series, Vol. 393, proceedings of the conference held 14-1

Astronomy and Astrophysics

Astronomy

Scientific paper

The merging galaxy cluster 1E 0657-56, known as the ``bullet cluster,'' is one of the hottest clusters known. The X-ray emitting plasma exhibits bow-shock-like temperature and density jumps. The segregation of this plasma from the peaks of the mass distribution determined by gravitational lensing has been interpreted as a direct proof of collisionless dark matter. If the high shock speed inferred from the shock jump conditions equals the relative speed of the merging CDM halos, however, this merger is predicted to be such a rare event in a ΛCDM universe that observing it presents a possible conflict with the ΛCDM model.
We examined this question using high resolution, 2D simulations of gas dynamics in cluster collisions to analyze the relative motion of the clusters, the bow shock, and the contact discontinuity, and relate these to the X-ray data for the bullet cluster. We find that the velocity of the fluid shock need not equal the relative velocity of the CDM components. An illustrative simulation finds that the present relative velocity of the CDM halos is 16% lower than that of the shock. While this conclusion is sensitive to the detailed initial mass and gas density profiles of the colliding clusters, such a decrease of the inferred halo relative velocity would significantly increase the likelihood of finding 1E 0657-56 in a ΛCDM universe.

Affiliated with

Also associated with

No associations

Rating

The Cluster-Merger Shock in 1E 0657-56: Faster than a Speeding Bullet? 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 Cluster-Merger Shock in 1E 0657-56: Faster than a Speeding Bullet?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Cluster-Merger Shock in 1E 0657-56: Faster than a Speeding Bullet? will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1690694