相关论文: A Dynamical Analysis of the Poor Galaxy Clusters A…

We report 102 new redshifts and magnitudes for a sample of galaxies to RF ~ 15.5 mag in a 2.17 deg x 2.17 deg region centered on the galaxy IC 4296, the most luminous member of the A3565 cluster. Up to the limiting magnitude we find 29…

X-ray and radio observations of CIZA J2242.8+5301 suggest that it is a major cluster merger. Despite being well studied in the X-ray, and radio, little has been presented on the cluster structure and dynamics inferred from its galaxy…

We report the discovery of a binary galaxy cluster merger via a search of the redMaPPer optical cluster catalog, with a projected separation of 535 kpc between the BCGs. Archival XMM-Newton spectro-imaging reveals a gas peak between the…

We constrain the mass-to-light ratios, gas mass fractions, baryon mass fractions and the ratios of total to luminous mass for a sample of eight nearby relaxed galaxy groups and clusters: A262, A426, A478, A1795, A2052, A2063, A2199 and…

Optical imaging and spectroscopic observations of the z = 0.245 double galaxy cluster Abell 2465 are described. This object appears to be undergoing a major merger. It is a double X-ray source and is detected in the radio at 1.4 GHz. This…

Galaxy cluster mergers that exhibit clear dissociation between their dark matter, intracluster gas, and stellar components are great laboratories for probing dark matter properties. Mergers that are binary and in the plane of the sky have…

The galaxy cluster A3667 was observed using the Two-degree Field (2dF) multifibre spectroscopic system on the Anglo-Australian Telescope in a program designed to examine the velocity structure in the region. Specifically, we sought evidence…

From the poor cluster catalog of White et al. (1996), we define a sample of 71 optically-selected poor galaxy clusters. The surface-density enhance- ment we require for our clusters falls between that of the loose associations of Turner and…

The cluster A3627 was recently recognized to be a very massive, nearby cluster in a galaxy survey close to the galactic plane. We are reporting on ROSAT PSPC observations of this object which confirm that the cluster is indeed very massive.…

We present spectroscopic confirmation of nine moderate redshift galaxy groups and poor clusters selected from the ROSAT Deep Cluster Survey. The groups span the redshift range z=0.23-0.59 and have between 4 and 20 confirmed members. The…

To investigate the dynamics of the galaxy cluster A2142, we compile an extended catalog of 2239 spectroscopic redshifts of sources, including newly measured 237 redshifts, within 30 arcmin from the cluster center. With the $\sigma$-plateau…

Abell 2146 ($z$ = 0.232) consists of two galaxy clusters undergoing a major merger. The system was discovered in previous work, where two large shock fronts were detected using the $\textit{Chandra X-ray Observatory}$, consistent with a…

We have initiated a program to study the baryon content and dynamic state of galaxy clusters. Here we present results primarily from XMM-Newton observations of two optically-selected galaxy clusters, A1095 ($z \simeq 0.210$) and A1926 ($z…

We analyze the internal structures of clusters A1689 and A2218 by applying a recent development of the method of wavelet analysis, which uses the complete information obtained from optical data, i.e. galaxy positions and redshifts. We find…

We present new Chandra observations of a high redshift (z~1) galaxy cluster discovered in the Red-Sequence Cluster Survey (RCS): RCS043938-2904.7. X-ray luminosity measurements and mass estimates are consistent with L_X-T_X and M_delta-T_X…

We present MMT spectroscopic observations of two massive galaxy cluster candidates at redshift $z\sim0.07$ that show extended and diffuse X-ray emission in the ROSAT All Sky Survey (RASS) images. The targets were selected from a previous…

The MS1224+20 cluster of galaxies is a high luminosity X-ray source at z=0.325. To compare the lensing mass to the virial mass we have completed a uniform, high precision redshift survey over a field of $7\arcm\times9\arcm$, obtaining 75…

We study three prominent bi-modal X-ray clusters: A3528, A1750 and A3395. Using observations taken with ROSAT and ASCA, we analyze the temperature and surface brightness distributions. We also analyze the velocity distributions of the three…

We present a multi-wavelength study of the massive ($M_{200\textrm{c}} \approx 1$-$2 \times 10^{15} M_\odot$) galaxy clusters RXC J2248.7$-$4431, MACS J0416.1$-$2403, and MACS J1206.2$-$0847 at $z \approx 0.4$. Using the X-ray surface…

We present new Chandra X-ray observations of the luminous X-ray cluster, MS0451.6-0305, at z=0.5386. Spectral imaging data for the cluster are consistent with an isothermal cluster of 10.0 - 10.6 +/-1.6 keV and an Fe abundance of 0.32-0.40…