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Context: Measurements of intracluster gas temperatures out to large radii are important for the use of clusters for precision cosmology and for studies of cluster physics. Previous attempts to measure robust temperatures at cluster virial radii failed. Aims: The goal of this work is to measure the temperature profile of the very relaxed galaxy cluster Abell 2204 out to large radii, possibly reaching the virial radius. Methods: Taking advantage of its low particle background due to its low-Earth orbit, Suzaku data are used to measure the outer temperature profile of Abell 2204. These data are combined with Chandra and XMM-Newton data of the same cluster in order to make the connection to the inner regions, unresolved by Suzaku, and to determine the smearing due to Suzaku's PSF. Results: The temperature profile of Abell 2204 is determined from 10 kpc to 1800 kpc, close to an estimate of r200 (the approximation to the virial radius). The temperature rises steeply from below 4 keV in the very center up to more than 8 keV in the intermediate range and then decreases again to about 4 keV at the largest radii. Varying the measured particle background normalization artificially by +-10 percent does not change the results significantly. Predictions for outer temperature profiles based on hydrodynamic simulations show good agreement. In particular, we find the observed temperature profile to be slightly steeper but consistent with a drop of a factor of 0.6 from 0.3 r200 to r200, as predicted by simulations. Conclusions: Temperature measurements up to the virial radius seem feasible with Suzaku, when a careful analysis of the different background components and the effects of the PSF is performed. The result obtained here indicates that numerical simulations capture the intracluster gas physics well in cluster outskirts., Comment: 7 pages; Astronomy and Astrophysics, accepted; additional systematic effects have been quantified, results unchanged; also available at http://www.reiprich.net

We present the X-ray properties of a massive cluster of galaxies (RXCJ2228.6+2036 at $z=0.421$) using {\it XMM-Newton} data. The X-ray mass modeling is based on the temperature and density distributions of the intracluster medium derived using a deprojection method. We found that RXCJ2228.6+2036 is a hot cluster ($T_{500}=8.92^{+1.78}_{-1.32}$ keV) showing a cooling flow rate of $12.0^{+56.0}_{-12.0}$ M$_{\odot}$yr$^{-1}$ based on spectral fitting within the cooling flow radius ($r_{cool}=147\pm10$ kpc). The total cluster mass is $M_{500}=(1.19\pm0.35)\times10^{15}$ M$_{\odot}$ and the mean gas mass fraction is $f_{gas}=0.165\pm0.045$ at $r_{500}=1.61\pm0.16$ Mpc. We discussed the PSF-correction effect on the spectral analysis and found that for the annular width we chose the PSF-corrected temperatures are consistent with those without PSF-correction. We observed a remarkable agreement between X-ray and SZ results, which is of prime importance for the future SZ survey. RXCJ2228.6+2036 obeys the empirical scaling relations found in general massive galaxy clusters (e.g. $S$--$T$, $M$--$T$, $L$--$T$ and $M$--$Y$) after accounting for self-similar evolution., Comment: 10 pages, 14 figures

[Abridged] We searched for diffuse stellar emission around BCGs in three of the most X-ray luminous clusters found at z~0.3 in the REFLEX cluster survey and observed with XMM-Newton. These systems (RXCJ0014.3-3022, RXCJ0232.2-4420, and RXCJ2308.3-0211) are in different dynamical states, as witnessed by their X-ray morphology and optical appearence (e.g. multiplicity of BCGs). [Abridged] Diffuse stellar emission is robustly detected down to a surface brightness of 26 R-mag/arcsec^2 (observed frame) around a total of seven BCGs, extending up to galactocentric distances of ~100 kpc. In particular, it surrounds a pair of BCGs in RXCJ0232.2-4420, while it bridges two BCGs associated with the minor subcomponent of the merging cluster RXCJ0014.3-3022. The diffuse light detected at the greatest distances from the BCGs of the rather regular clusters RXCJ0232.2-4420 and RXCJ2308.3-0211 follows the ICM distribution. Its B-R colour is consistent with the colours measured within the BCG effective radii. The diffuse light around the two pairs of BCGs in RXCJ0014.3-3022 exhibits bluer colours than the BCG central regions by up to 0.5 mag. If the contribution of the intracluster light (ICL) to the detected diffuse light around BCGs is not negligible, ICL and BCGs have similar stellar populations in relatively relaxed clusters. Merging on a cluster scale eventually adds gravitational stresses to BCGs and other galaxies in subcluster cores. This event may affect the properties of the diffuse stellar emission around BCGs. Shredding of star-forming, low-metallicity dwarf galaxies is favoured as the cause of the bluer B-R colours of the diffuse stellar component around the two pairs of BCGs in the merging cluster RXCJ0014.3-3022., Comment: 20 pages including 3 tables and 11 low-resolution colour figures, accepted for publication in A&A

The Local Cluster Substructure Survey (LoCuSS, Smith et al.) is a systematic multi-wavelength survey of >100 X-ray luminous galaxy clusters (0.14

The largest uncertainty for cosmological studies using clusters of galaxies is introduced by our limited knowledge of the statistics of galaxy cluster structure, and of the scaling relations between observables and cluster mass. To improve on this situation we have started an XMM-Newton Large Programme for the in-depth study of a representative sample of 33 galaxy clusters, selected in the redshift range z=0.055 to 0.183 from the REFLEX Cluster Survey, having X-ray luminosities above 0.4 X 10^44 h_70^-2 erg s^-1 in the 0.1 - 2.4 keV band. This paper introduces the sample, compiles properties of the clusters, and provides detailed information on the sample selection function. We describe the selection of a nearby galaxy cluster sample that makes optimal use of the XMM-Newton field-of-view, and provides nearly homogeneous X-ray luminosity coverage for the full range from poor clusters to the most massive objects in the Universe. For the clusters in the sample, X-ray fluxes are derived and compared to the previously obtained fluxes from the ROSAT All-Sky Survey. We find that the fluxes and the flux errors have been reliably determined in the ROSAT All-Sky Survey analysis used for the REFLEX Survey. We use the sample selection function documented in detail in this paper to determine the X-ray luminosity function, and compare it with the luminosity function of the entire REFLEX sample. We also discuss morphological peculiarities of some of the sample members. The sample and some of the background data given in this introductory paper will be important for the application of these data in the detailed studies of cluster structure, to appear in forthcoming publications., Comment: 17 pages, 17 figures; to appear in A&A. A pdf version with full-quality figures can be found at ftp://ftp.xray.mpe.mpg.de/people/gwp/xmmlp/xmmlp.pdf

We present the X-ray properties and scaling relations of a flux-limited morphology-unbiased sample of 12 X-ray luminous galaxy clusters at redshift around 0.2 based on XMM-Newton observations. The scaled radial profiles are characterized by a self-similar behavior at radii outside the cluster cores (>0.2 r500) for the temperature, surface brightness, entropy, gas mass and total mass. The cluster cores contribute up to 70% of the bolometric X-ray luminosity. The X-ray scaling relations and their scatter are sensitive to the presence of the cool cores. Using the X-ray luminosity corrected for the cluster central region and the temperature measured excluding the cluster central region, the normalization agrees to better than 10% for the cool core clusters and non-cool core clusters, irrelevant to the cluster morphology. No evolution of the X-ray scaling relations was observed comparing this sample to the nearby and more distant samples. With the current observations, the cluster temperature and luminosity can be used as reliable mass indicators with the mass scatter within 20%. Mass discrepancies remain between X-ray and lensing and lead to larger scatter in the scaling relations using the lensing masses (e.g. ~40% for the luminosity--mass relation) than using the X-ray masses (<20%) due to the possible reasons discussed., Comment: 38 pages, 25 figures, 6 tables, A&A, in press (references updated)

We present a statistical study of the occurrence and effects of the cooling cores in the clusters of galaxies in a flux-limited sample, HIFLUGCS, based on ROSAT and ASCA observations. About 49% of the clusters in this sample have a significant, classically-calculated cooling-flow, mass-deposition rate. The upper envelope of the derived mass-deposition rate is roughly proportional to the cluster mass, and the fraction of cooling core clusters is found to decrease with it. The cooling core clusters are found to have smaller core radii than non-cooling core clusters, while some non-cooling core clusters have high $\beta$ values (> 0.8). In the relation of the X-ray luminosity vs. the temperature and the mass, the cooling core clusters show a significantly higher normalization. A systematic correlation analysis, also involving relations of the gas mass and the total infrared luminosity, indicates that this bias is shown to be mostly due to an enhanced X-ray luminosity for cooling core clusters, while the other parameters, like temperature, mass, and gas mass may be less affected by the occurrence of a cooling core. These results may be explained by at least some of the non-cooling core clusters being in dynamically young states compared with cooling core clusters, and they may turn into cooling core clusters in a later evolutionary stage., Comment: A&A accepted

We selected an unbiased, flux-limited and almost volume-complete sample of 13 distant, X-ray luminous (DXL, $z\sim 0.3$) clusters and one supplementary cluster at $z=0.2578$ from the REFLEX Survey (the REFLEX-DXL sample). We performed a detailed study to explore their X-ray properties using XMM-Newton observations. Based on the precise radial distributions of the gas density and temperature, we obtained robust cluster masses and gas mass fractions. The average gas mass fraction of the REFLEX-DXL sample at $r_{500}$, $0.116 \pm 0.007$, agrees with the previous cluster studies and the WMAP baryon fraction measurement. The scaled profiles of the surface brightness, temperature, entropy, gas mass and total mass are characterized by a self-similar behaviour at radii above 0.2--0.3 $r_{500}$. The REFLEX-DXL sample confirms the previous studies of the normalization of the scaling relations ($L$--$T$, $L$--$M$, $M$--$T$ and $M_{\rm gas}$--$T$) when the redshift evolution of the scaling relations is accounted for. We investigated the scatter of the scaling relations of the REFLEX-DXL sample. This gives the correlative scatter of (0.20,0.10) for variable of ($M$,$T$) of the $M_{500}$--$T$ relation, for example., Comment: Astronomy and Astrophysics, Volume 456, Issue 1, September II 2006, pp.55-74

A CHANDRA follow-up observation of an X-ray luminous galaxy cluster with a compact appearance, RXCJ1504.1-0248 discovered in our REFLEX Cluster Survey, reveals an object with one of the most prominent cluster cooling cores. With a core radius of ~30 kpc smaller than the cooling radius with ~140 kpc more than 70% of the high X-ray luminosity of Lbol = 4.3 10e45 erg s-1 of this cluster is radiated inside the cooling radius. A simple modeling of the X-ray morphology of the cluster leads to a formal mass deposition rate within the classical cooling flow model of 1500 - 1900 Msun yr-1 (for h=0.7), and 2300 - 3000 Msun yr-1 (for h=0.5). The center of the cluster is marked by a giant elliptical galaxy which is also a known radio source. Thus it is very likely that we observe one of the interaction systems where the central cluster AGN is heating the cooling core region in a self-regulated way to prevent a massive cooling of the gas, similar to several such cases studied in detail in more nearby clusters. The interest raised by this system is then due to the high power recycled in RXCJ1504-0248 over cooling time scales which is about one order of magnitude higher than what occurs in the studied, nearby cooling core clusters. The cluster is also found to be very massive, with a global X-ray temperature of about 10.5 keV and a total mass of about 1.7 10e15 Msun inside 3 Mpc., Comment: accepted for publication in Astrophys. Journal, 10 figures

We put together the results of XMM-Newton observations of a number of representative group and cluster samples at low and high redshifts. These results confirm the entropy ramp as an explanation of the observed scaling relations. We observe a mild evolution in the entropy of clusters. The observed degree of evolution is consistent with expectations of the shock heating at a fixed overdensity (500) with respect to the critical density in LCDM. The study of the evolution in the pressure scaling imposes strong requirements in the definition of the average temperature of the cluster. The scaling temperature should be consistent to better than the 10% level. Once such a consistency is achieved, no additional evolution in the pressure has been detected in addition to the prediction of the shock heating in the LCDM Universe., Comment: 8 pages, Adv. in Space Research, in press

The precise determination of global properties of galaxy clusters, and their scaling relations, is a task of prime importance for the use of clusters as cosmological probes. We performed a detailed XMM-Newton study of 14 X-ray luminous REFLEX Survey clusters at z~0.3. We found that the properties of the galaxy clusters show a self-similar behavior at r>0.1r_{vir}. This helps to establish tighter scaling relations. Peculiarities in the individual clusters are important to understand the scatter from the self-similar frame in the cluster central parts., Comment: 10 pages, 4 figures, contribution to the Proceedings of the COSPAR Scientific Assembly, E1.2 "Clusters of Galaxies: New Insights from XMM-Newton, Chandra and INTEGRAL", Paris (France), July 19-20, 2004, accepted for publication in Advances in Space Research

We present a detailed gravitational mass measurement based on the XMM-Newton imaging spectroscopy analysis of the lensing cluster of galaxies CL0024+17 at z=0.395. The emission appears approximately symmetric. However, on the scale of r~3.3' some indication of elongation is visible in the northwest-southeast (NW-SE) direction from the hardness ratio map (HRM). Within 3', we measure a global gas temperature of 3.52\pm0.17 keV, metallicity of 0.22\pm0.07, and bolometric luminosity of 2.9\pm0.1 \times 10^{44} h^{-2}_{70} erg/s. We derive a temperature distribution with an isothermal temperature of 3.9 keV to a radius of 1.5' and a temperature gradient in the outskirts (1.3

We present XMM-Newton results on the spatially resolved temperature profiles of eight massive galaxy clusters of a volume-limited sample at redshifts $z\sim0.3$ (REFLEX-DXL sample) and an additional luminous cluster at $z=0.2578$, selected from the REFLEX survey. Useful temperature measurements could be performed out to radii with overdensity 500 ($r_{500}$). The scaled temperature distributions show good similarities. We discovered diversities in the temperature gradients at the outer cluster radii with examples of both flat and strongly decreasing profiles which call for different physical interpretations. We found an indication of the 'warm-hot' gas existing in or around the hot clusters. Using RXCJ0307.0-2840 we demonstrate that the errors on the mass estimates are within 25% up to r_{500}., Comment: 6 pages, 6 figures, to appear in the proceedings of "Modelling the Intergalactic and Intracluster Media", Vulcano Italy, October 1-4, 2003

We present XMM-Newton results on the temperature profiles of a volume-limited sample of galaxy clusters at redshifts z~0.3, selected from the REFLEX survey (REFLEX-DXL sample). In the spectral analysis, where only the energies above 1 keV were considered, we obtained consistent results on the temperature derived from the EPN, EMOS1 and EMOS2 data. Useful temperature measurements could be performed out to radii with overdensity 500 (r500) for all nine clusters. We discovered a diversity in the temperature gradients at the outer cluster radii with examples of both flat and strongly decreasing profiles. Using the total mass and the gas mass profiles for the cluster RXCJ0307.0-2840 we demonstrate that the errors on the mass estimates for the REFLEX-DXL clusters are within 25% up to r500., Comment: Revised version accepted for publication in A&A, 18 pages