NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-07-17 T03:38:44 PDT
Help | Comment | NED Home

For refcode 2010A&A...517A..92A:
Retrieve 34 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by European Southern Observatory (ESO). Reproduced by permission
2010A&A...517A..92A The universal galaxy cluster pressure profile from a representative sample of nearby systems (REXCESS) and the Y_SZ_ - M_500_ relation Arnaud, M.; Pratt, G. W.; Piffaretti, R.; Bohringer, H.; Croston, J. H.; Pointecouteau, E. Abstract. We investigate the regularity of cluster pressure profiles with REXCESS, a representative sample of 33 local (z < 0.2) clusters drawn from the REFLEX catalogue and observed with XMM-Newton. The sample spans a mass range of 10^14^ M_o_ < M_500_ < 10^15^ M_o_, where M_500_ is the mass corresponding to a density contrast of 500. We derive an average profile from observations scaled by mass and redshift according to the standard self-similar model, and find that the dispersion about the mean is remarkably low, at less than 30 per cent beyond 0.2 R_500_, but increases towards the center. Deviations about the mean are related to both the mass and the thermo-dynamical state of the cluster. Morphologically disturbed systems have systematically shallower profiles while cooling core systems are more concentrated. The scaled profiles exhibit a residual mass dependence with a slope of ~0.12, consistent with that expected from the empirically-derived slope of the M_500_ - Y_X_ relation; however, the departure from standard scaling decreases with radius and is consistent with zero at R_500_. The scatter in the core and departure from self-similar mass scaling is smaller compared to that of the entropy profiles, showing that the pressure is the quantity least affected by dynamical history and non-gravitational physics. Comparison with scaled data from several state of the art numerical simulations shows good agreement outside the core. Combining the observational data in the radial range [0.03-1] R_500_ with simulation data in the radial range [1-4] R_500_, we derive a robust measure of the universal pressure profile, that, in an analytical form, defines the physical pressure profile of clusters as a function of mass and redshift up to the cluster "boundary". Using this profile and direct spherical integration of the observed pressure profiles, we estimate the integrated Compton parameter Y and investigate its scaling with M_500_ and L_X_, the soft band X-ray luminosity. We consider both the spherically integrated quantity, Y_sph_(R), proportional to the gas thermal energy, and the cylindrically integrated quantity, Y_cyl_(R)=Y_SZ_ D_A_^2^, which is directly related to the Sunyaev-Zel'dovich (SZ) effect signal. From the low scatter of the observed Y_sph_(R_500_) - Y_X_ relation we show that variations in pressure profile shape do not introduce extra scatter into the Y_sph_(R_500_) - M_500_ relation as compared to that from the Y_X_ - M_500_ relation. The Y_sph_(R_500_) - M_500_ and Y_sph_(R_500_) - L_X_ relations derived from the data are in excellent agreement with those expected from the universal profile. This profile is used to derive the expected Y_SZ_ - M_500_ and Y_SZ_ - L_X_ relations for any aperture. Key words: cosmology: observations, dark matter, galaxies: clusters: general, intergalactic, medium, X-rays: galaxies: clusters
Retrieve 34 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home