Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-11-25
Astronomy and Astrophysics
Astrophysics
18 pages, 20 figures, 7 tables, accepted for publication in MNRAS, minor changes to match published version
Scientific paper
10.1111/j.1365-2966.2008.13116.x
We carry out a comprehensive joint analysis of high quality HST/ACS and Chandra measurements of A1689, from which we derive mass, temperature, X-ray emission and abundance profiles. The X-ray emission is smooth and symmetric, and the lensing mass is centrally concentrated indicating a relaxed cluster. Assuming hydrostatic equilibrium we deduce a 3D mass profile that agrees simultaneously with both the lensing and X-ray measurements. However, the projected temperature profile predicted with this 3D mass profile exceeds the observed temperature by ~30% at all radii, a level of discrepancy comparable to the level found for other relaxed clusters. This result may support recent suggestions from hydrodynamical simulations that denser, more X-ray luminous small-scale structure can bias observed temperature measurements downward at about the same (~30%) level. We determine the gas entropy at 0.1r_{vir} (where r_{vir} is the virial radius) to be ~800 keV cm^2, as expected for a high temperature cluster, but its profile at >0.1r_{vir} has a power-law form with index ~0.8, considerably shallower than the ~1.1 index advocated by theoretical studies and simulations. Moreover, if a constant entropy ''floor'' exists at all, then it is within a small region in the inner core, r<0.02r_{vir}, in accord with previous theoretical studies of massive clusters.
Barkana Rennan
Broadhurst Tom J.
Lemze Doron
Rephaeli Yoel
No associations
LandOfFree
Mass and Gas Profiles in A1689: Joint X-ray and Lensing Analysis 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 Mass and Gas Profiles in A1689: Joint X-ray and Lensing Analysis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mass and Gas Profiles in A1689: Joint X-ray and Lensing Analysis will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-512144