Now showing items 31-40 of 76
A large air shower array to search for astrophysical sources emitting [gamma]-rays with energies >=1014 eV
(Elsevier, 1994-07-15)
We describe the technical details and the performance of a large array which detects both the electron and muon components in extensive air showers with energies >= 1014 eV. The array was designed to search for [gamma]-rays ...
Cluster-supercluster alignments
(Univ Chicago Press, 2007-03-01)
We study correlations in spatial orientation between galaxy clusters and their host superclusters using a Hubble volume N-body realization of a concordance cosmology and an analytic model for tidally induced alignments. ...
Substructure in clusters as a cosmological test
(Univ Chicago Press, 1996-08-20)
We use N-body simulations to test the dependence of cluster substructure on four cosmologies and three initial power spectra. Our purpose is to quantify the amount of substructure in each model and understand these results ...
Rosat Observations of Compact-Groups of Galaxies
(Univ Chicago Press, 1995-04-20)
We have systematically analyzed a sample of 13 new and archival ROSAT Position Sensitive Proportional Counter observations of compact groups of galaxies: 12 Hickson compact groups plus the NCG 2300 group. We find that ...
Radial temperature profiles of X-ray-emitting gas within clusters of galaxies
(Univ Chicago Press, 1999-07-10)
Previous analyses of ASCA data of clusters of galaxies have found conflicting results regarding the slope of the temperature profile of the hot X-ray gas within clusters, mainly because of the large, energy-dependent ...
Properties of simulated compact groups of galaxies
(Amer Inst Physics, 1996-08)
We analyze compact groups of galaxies appearing in a galaxy formation simulation dominated by cold dark matter (Omega(0)=1, Omega(baryon)=0.1). The simulation uses an N-body code to model the behavior of the non-baryonic ...
Previrialization
(Univ Chicago Press, 1992-07-20)
We report the results of N-body experiments employing Gaussian random initial conditions designed to address the effect of previrialization recently examined by Peebles. The central issue is whether the development of ...
The asymptotic form of cosmic structure: Small-scale power and accretion history
(Univ Chicago Press, 2007-08-10)
We explore the effects of small-scale structure on the formation and equilibrium of dark matter halos in a universe dominated by vacuum energy. We present the results of a suite of four N-body simulations, two with a Lambda ...
The merger in abell 576: A line-of-sight bullet cluster?
(Univ Chicago Press, 2007-10-20)
Using a combination of Chandra and XMM-Newton observations, we confirmed the presence of a significant velocity gradient along the northeast-southwest direction in the intracluster gas of the cluster Abell 576. The results ...
The temperature-mass relation in magnetized galaxy clusters
(EDP Sciences, 2001-04-01)
We use cosmological, magneto-hydrodynamic simulations of galaxy clusters to quantify the dynamical importance of magnetic fields in these clusters. The set-up of initial magnetic field strengths at high redshifts is chosen ...