Systematics in the X-ray Cluster Mass Estimators

Details Systematics in the X-ray Cluster Mass Estimators Systematics in the X-ray Cluster Mass Estimators

2006-02-20

arxiv.org/abs/astro-ph/0602434v1

Mon.Not.Roy.Astron.Soc.369:2013-2024,2006

Astronomy and Astrophysics

Astrophysics

submitted to MNRAS, 12 pages

Scientific paper

10.1111/j.1365-2966.2006.10466.x

We examine the systematics affecting the X-ray mass estimators applied to a set of five simulated galaxy clusters. They have been processed through the X-ray Map Simulator, X-MAS, to provide Chandra-like long exposures that are analyzed to reconstruct the gas temperature, density, and mass profiles used as input. We find that at R_2500 the mass profile obtained via a direct application of the hydrostatic equilibrium equation is consistent within 1 sigma with the actual mass; although we notice this estimator shows high statistical errors due to high level of Chandra background. Instead, the poorness of the beta-model in describing the gas density profile makes the evaluated masses to be underestimated by \sim 40 per cent with respect to the true mass, both with an isothermal and a polytropic temperature profile. We also test ways to recover the mass by adopting an analytic mass model, such as those proposed by Navarro et al. (1997) and Rasia et al. (2004), and fitting the temperature profile expected from the hydrostatic equilibrium equation to the observed one. These methods and the one of the hydrostatic equilibrium equation provide a more robust mass estimation than the ones based on the beta-model. In the present work the main limitation for a precise mass reconstruction is to ascribe to the relatively high level of the background chosen to reproduce the Chandra one. After artificially reducing it by a factor of 100, we find that the estimated mass significantly underestimates the true mass profiles. This is manly due (i) to the neglected contribution of the gas bulk motions to the total energy budget and (ii) to the bias towards lower values of the X-ray temperature measurements because of the complex thermal structure of the emitting plasma.

Affiliated with

Also associated with

No associations

Rating

Systematics in the X-ray Cluster Mass Estimators 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 Systematics in the X-ray Cluster Mass Estimators, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Systematics in the X-ray Cluster Mass Estimators will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-520201