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We present an early broad-brush analysis of Herschel/PACS observations of star-forming galaxies in 8 galaxy clusters drawn from our survey of 30 clusters at z~0.2. We define a complete sample of 192 spectroscopically confirmed cluster members down to L_TIR>3x10^10L_sun and L_K>0.25L_sun. The average K-band and bolometric infrared luminosities of these galaxies both fade by a factor of ~2 from clustercentric radii of 2r_200 to ~0.5r_200, indicating that as galaxies enter the clusters ongoing star-formation stops first in the most massive galaxies, and that the specific star-formation rate (SSFR) is conserved. On smaller scales the average SSFR jumps by 25%, suggesting that in cluster cores processes including ram pressure stripping may trigger a final episode of star-formation that presumably exhausts the remaining gas. This picture is consistent with our comparison of the Herschel-detected cluster members with the cluster mass distributions, as measured in our previous weak-lensing study of these clusters. For example, the spatial distribution of the Herschel sources is positively correlated with the structures in the weak-lensing mass maps at 5sigma significance, with the strongest signal seen at intermediate group-like densities. The strong dependence of the total cluster IR luminosity on cluster mass L_TIR propto M_virial^2 is also consistent with accretion of galaxies and groups of galaxies (i.e. the substructure mass function) driving the cluster IR luminosity. The most surprising result is that roughly half of the Herschel-detected cluster members have redder S_100/S_24 flux ratios than expected, based on the Rieke et al. models. On average cluster members are redder than non-members, and the fraction of red galaxies increases towards the cluster centers, both of which indicate that these colors are not attributable to systematic photometric errors. [Abridged]
We test the assumption of hydrostatic equilibrium in an X-ray luminosity selected sample of 50 galaxy clusters at $0.15<z<0.3$ from the Local Cluster Substructure Survey (LoCuSS). Our weak-lensing measurements of $M_{500}$ control systematic biases t
We present Herschel/PACS, MMT/Hectospec and XMM-Newton observations of Abell 1835, one of the brightest X-ray clusters on the sky, and the host of a strong cool core. Even though Abell 1835 has a prototypically relaxed X-ray morphology and no signs o
(Abridged) We use Subaru data to conduct a detailed weak-lensing study of the dark matter distribution in a sample of 30 X-ray luminous galaxy clusters at 0.15<z<0.3. A weak-lensing signal is detected at high statistical significance in each cluster,
Chiral symmetry is maximally violated in weak interactions, and such microscopic asymmetries in the early Universe might leave observable imprints on astrophysical scales without violating the cosmological principle. In this Letter, we propose a heli
We present wide-field Herschel/PACS observations of Abell 1689, a massive galaxy cluster at z=0.1832, from our Open Time Key Programme. We detect 39 spectroscopically confirmed 100micron-selected cluster members down to 1.5x10^10 Lsun. These galaxies