Related papers: Vector dark energy and high-z massive clusters
We present a very large high-resolution cosmological N-body simulation, the Millennium-XXL or MXXL, which uses 303 billion particles to represent the formation of dark matter structures throughout a 4.1Gpc box in a LambdaCDM cosmology. We…
The introduction of electroweak multiplets that transform under any representation of the standard $SU(2)_L$ gauge group suggests the existence of electrically neutral stable particles capable of serving as cold dark matter in the…
We use hydrodynamical/N-body simulations to interpret the newly discovered Bullet-cluster-like merging cluster, ZwCl 0008.8+5215 (ZwCl 0008 hereafter), where a dramatic collision is apparent from multi-wavelength observations. We have been…
We briefly discuss the expected level of supersymmetric dark matter cross-sections as a reference for dark matter detectors. We then discuss the current ZEPLIN II program as a prototype of large liquid Xenon detectors. Cryoarray is a…
We construct a model based on a new $U(1)_X$ gauge symmetry and a discrete $Z_2$ symmetry under which the new gauge boson is odd. The model contains new complex scalars which carry $U(1)_X$ charge but are singlets of the Standard Model. The…
The exponential sensitivity of cluster number counts to the properties of the dark energy implies a comparable sensitivity to not only the mean but also the actual_distribution_ of an observable mass proxy given the true cluster mass. For…
Early data from the James Webb Space Telescope (JWST) has uncovered the existence of a surprisingly abundant population of very massive galaxies at extremely high redshift, which are hard to accommodate within the standard $\Lambda$CDM…
The canonical cosmological model to explain the recent acceleration of the universe relies on a cosmological constant, and most dynamical dark energy and modified gravity model alternatives are based on scalar fields. Still, further…
MSSM4G models, in which the minimal supersymmetric standard model is extended to include vector-like copies of standard model particles, are promising possibilities for weak-scale supersymmetry. In particular, two models, called QUE and…
Existing data hints that high energy cosmic ray experiments may offer the most promissing shot at finding a dark matter particle. A search in the PeV mass range is suggested, where the discovery of such a particle might help explain the GZK…
We study the possibility for detecting gamma-ray emission from galaxy clusters. We consider 1) leptophilic models of dark matter (DM) annihilation that include a Sommerfeld enhancement (SFE), 2) different representative benchmark models of…
The recent weak lensing measurement of the dark matter mass of the high-redshift galaxy cluster XMMUJ2235.3-2557 of (8.5 +- 1.7) x 10^{14} Msun at z=1.4, indicates that, if the cluster is assumed to be the result of the collapse of dark…
The Dark Energy Survey (DES) will be unprecedented in its ability to probe exceptionally large cosmic volumes to relatively faint optical limits. Primarily designed for the study of comparatively low redshift (z<2) galaxies with the aim of…
We show that hidden hot dark matter, hidden-sector dark matter with interactions that decouple when it is relativistic, is a viable dark matter candidate provided it has never been in thermal equilibrium with the particles of the standard…
I present an overview of theoretical expectations for detection of dark matter (DM) at the LHC, concentrating entirely on supersymmetric candidates. En route, I present a unified theory which explains dark matter signals at indirect and…
I briefly review our current understanding of dark matter and dark energy. The first part of this paper focusses on issues pertaining to dark matter including observational evidence for its existence, current constraints and the `abundance…
We report the discovery of XMMXCS J2215.9-1738, a massive galaxy cluster at z =1.45, which was found in the XMM Cluster Survey. The cluster candidate was initially identified as an extended X-ray source in archival XMM data. Optical…
In the cosmological paradigm, cold dark matter (DM) dominates the mass content of the Universe and is present at every scale. Candidates for DM include many extensions of the standard model, with a weakly interacting massive particle (WIMP)…
During the course of a gravitational lensing survey of distant, X-ray selected, EMSS clusters of galaxies, we have studied 6 X-ray luminous (Lx > 5x10^44 h_{50}^{-2} erg s^{-1}) clusters at redshifts exceeding z=0.5. All of these clusters…
We present Sunyaev-Zel'dovich Effect (SZE) imaging observations of three distant (z > 0.8) and highly X-ray luminous clusters of galaxies, Cl1226+33, Cl0152-13 and MS1054-03. Two of the clusters, Cl1226+33 and Cl0152-13, were recently…