We investigate the growth over time of 20 massive (>3 keV) clusters in a hydrodynamical simulation of the cold dark matter cosmology with radiative cooling. The clusters show a variety of formation histories: some accrete most of their mass in major mergers; others, more gradually. During major mergers, the long-term (temporally smoothed) luminosity increases such that the cluster moves approxi...

We present a precise estimate of the bulk virial scaling relation of halos formed via hierarchical clustering in an ensemble of simulated cold dark matter cosmologies. The result is insensitive to cosmological parameters, the presence of a trace, dissipationless gas component, and numerical resolution down to a limit of ∼ 1000 particles. The dark matter velocity dispersion scales with total mas...

Context. The luminous material in clusters of galaxies exists in two forms: the visible galaxies and the X-ray emitting intra-cluster medium. The hot intra-cluster gas is the major observed baryonic component of clusters, about six times more massive than the stellar component. The mass contained within visible galaxies is approximately 3% of the dynamical mass. Aims. Our aim was to analyze bot...

We present a uniform analysis of the ROSAT HRI and the ASCA GIS/SIS data for 79 distant clusters of galaxies in the redshift range, 0.1 < z < 0.82 to study the global structures of the intracluster medium. We have constructed an X-ray catalog consisting of the largest sample of clusters in the redshift range for which pointed X-ray observations were carried out with both the observatories. We d...

We present comparison of X-ray proxies for the total cluster mass, including the spectral temperature (TX), gas mass measured within r500 (Mg), and the new proxy, YX, which is a simple product of TX and Mg and is related to the total thermal energy of the ICM. We use mock Chandra images constructed for a sample of clusters simulated with the eulerian N-body+gasdynamics adaptive mesh refinement ...

We carry out a two-dimensional study of temperature, entropy and pressure distributions in a nearly volume-limited subsample of REFLEX clusters at redshift 0.3, the REFLEX-DXL. We use the observations gained by XMM-Newton, which cover the central 1−2× r500. We define the substructure in both entropy and pressure as a deviation from the mean profile of the sample. The non-parametric locally weig...

Per Lundqvist Dr., Lars Herbe M.Sc, The Royal Institute ofTechnology, Dept. of Energy Technology, S-100 44, Stockholm, Sweden Fax: +46 8 20 30 07 Tel: +46 8 790 74 52 Email: [email protected] There are several important issues when dealing with new refrigerants in a retrofit situation. This paper is however restricted to system performance and a discussion of methods suitable to determine ...

ABSTRACT We estimate the intracluster light (ICL) component within a sample of 18 clusters detected in XMM Cluster Survey (XCS) data using deep (?26.8 mag) Hyper Suprime-Cam Subaru Strategic Programme release 1 i-band data. apply rest-frame ?B = 25 mag arcsec?2 isophotal threshold to our clusters, below which we define as ICL an aperture RX,500 (X-ray R500) centred on brightest cluster galaxy (...

Objective: To establish the accuracy of an eight-polar tactile-electrode impedance method in the assessment of total body water (TBW). Design: Transversal study. Setting: University department. Subjects: Fifty healthy subjects (25 men and 25 women) with a mean (s.d.) age of 40 (12) y. Methods: TBW measured by deuterium oxide dilution; resistance (R) of arms, trunk and legs measured at frequenci...

We investigate the galaxy populations in seven X-ray selected, intermediateredshift groups (0.2 < z < 0.6). Overall, the galaxy populations in these systems are similar to those in clusters at the same redshift; they have large fractions of early-type galaxies (fe ∼ 70%) and small fractions of galaxies with significant star formation (f[OII] ∼ 30%). We do not observe a strong evolution in the g...