411 citations · 4.2k across the 42 of their papers we have counts for
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The X-ray Cluster Normalization of the Matter Power Spectrum
J. Patrick Henry, August E. Evrard, Henk Hoekstra +2
The number density of galaxy clusters provides tight statistical constraints on the matter fluctuation power spectrum normalization, traditionally phrased in terms of sigma_8, the…
Sersiclets - A Matched Filter Extension of Shapelets for Weak Lensing Studies
Wai-Hin Wayne Ngan, Ludovic Van Waerbeke, Andisheh Mahdavi +2
The precision study of dark matter using weak lensing by large scale structure is strongly constrained by the accuracy with which one can measure galaxy shapes. Several methods hav…
Optical Spectroscopy of Type Ia Supernovae
T. Matheson, R. P. Kirshner, P. Challis +19
We present 432 low-dispersion optical spectra of 32 Type Ia supernovae (SNe Ia) that also have well-calibrated light curves. The coverage ranges from 6 epochs to 36 epochs of spect…
Resurrecting the Red from the Dead: Optical Properties of BCGs in X-ray Luminous Clusters
C. Bildfell, H. Hoekstra, A. Babul +1
We present measurements of surface brightness and colour profiles for the brightest cluster galaxies (BCGs) in a sample of 48 X-ray luminous galaxy clusters. These data were obtain…
Evidence for Non-Hydrostatic Gas from the Cluster X-ray to Lensing Mass Ratio
A. Mahdavi, H. Hoekstra, A. Babul +1
Using a uniform analysis procedure, we measure spatially resolved weak gravitational lensing and hydrostatic X-ray masses for a sample of 18 clusters of galaxies. We find a radial…
Investigating the Relationship Between the Hot Gas and the Dark Matter Components of Galaxy Clusters
Leila C. Powell, Scott T. Kay, Arif Babul +1
Various differences in galaxy cluster properties derived from X-ray and weak lensing observations have been highlighted in the literature. One such difference is the observation of…
A Dark Core in Abell 520
A. Mahdavi, H. Hoekstra, A. Babul +2
The rich cluster Abell 520 (z=0.201) exhibits truly extreme and puzzling multi-wavelength characteristics. It may best be described as a "cosmic train wreck." It is a major merger…
Joint Analysis of Cluster Observations: I. Mass Profile of Abell 478 from Combined X-ray, Sunyaev-Z'eldovich, and Weak Lensing Data
A. Mahdavi, H. Hoekstra, A. Babul +3
We provide a new framework for the joint analysis of cluster observations (JACO) using simultaneous fits to X-ray, Sunyaev-Zel'dovich (SZ), and weak lensing data. Our method fits t…
The impact of mergers on relaxed X-ray clusters - II. Effects on global X-ray and SZ properties and their scaling relations
Gregory B. Poole, Arif Babul, Ian G. McCarthy +4
We use the suite of simulations presented in Poole et al (2006) to examine global X-ray and Sunyaev-Zel'dovich (SZ) observables for systems of merging relaxed X-ray clusters. In al…
UBVRI Light Curves of 44 Type Ia Supernovae
Saurabh Jha, Robert P. Kirshner, Peter Challis +2
We present UBVRI photometry of 44 type-Ia supernovae (SN Ia) observed from 1997 to 2001 as part of a continuing monitoring campaign at the Fred Lawrence Whipple Observatory of the…
The NGC 5846 Group: Dynamics and the Luminosity Function to M_R=-12
A. Mahdavi, N. Trentham, R. B. Tully
We conduct a photometric and spectroscopic survey of a 10 sq. deg. region surrounding the nearby NGC 5846 group of galaxies, using the Canada-France-Hawaii and Keck I telescopes to…
XMM-Newton and Gemini Observations of Eight RASSCALS Galaxy Groups
A. Mahdavi, A. Finoguenov, H. Boehringer +2
We study the distribution of gas pressure and entropy in eight groups of galaxies belonging to the ROSAT All-Sky Survey / Center for Astrophysics Loose Systems (RASSCALS). We use a…
K-band Properties of Well-Sampled Groups of Galaxies
M. Ramella, W. Boschin, M. J. Geller +2
We use a sample of 55 groups and 6 clusters of galaxies ranging in mass from 7 x 10^11 Msun to 1.5 x 10^15 Msun to examine the correlation of the Ks-band luminosity with mass disco…
A Redshift Survey of Nearby Galaxy Groups: the Shape of the Mass Density Profile
A. Mahdavi, M. J. Geller
We constrain the mass profile and orbital structure of nearby groups and clusters of galaxies. Our method yields the joint probability distribution of the density slope n, the velo…
A Generalized Potential with Adjustable Slope: A Hydrostatic Alternative to Cluster Cooling Flows
Andisheh Mahdavi
I discuss a new gravitational potential, Phi(r) ~ (r_0^n+r^n)^(-1/n), for modeling the mass distribution of spherical systems. This potential has a finite mass and generates a dens…
A Study of the Type II-Plateau Supernova 1999gi, and the Distance to its Host Galaxy, NGC 3184
Douglas C. Leonard, Alexei V. Filippenko, Weidong Li +10
We present optical spectra and photometry sampling the first six months after discovery of supernova (SN) 1999gi in NGC 3184. SN 1999gi is shown to be a Type II-plateau event with…
Mass Profile of the Infall Region of the Abell 2199 Supercluster
K. Rines, M. J. Geller, A. Diaferio +3
Using a redshift survey of 1323 galaxies (1092 new or remeasured) in a region of 95 square degrees centered on the nearby galaxy cluster Abell 2199, we analyze the supercluster con…
Optical Spectral Monitoring of XTE J1118+480 in Outburst: Evidence for a Precessing Accretion Disk?
M. A. P. Torres, P. J. Callanan, M. R. Garcia +7
We present spectroscopic observations of the X-ray transient XTE J1118+480 acquired during different epochs following the 2000 March outburst. We find that the emission line profil…
The LX-sigma Relation for Galaxies and Clusters of Galaxies
Andisheh Mahdavi, Margaret J. Geller
We demonstrate that individual elliptical galaxies and clusters of galaxies form a continuous X-ray luminosity---velocity dispersion (LX-sigma) relation. Our samples of 280 cluster…
X-ray Emitting Groups in the Infall Region of Abell 2199
K. Rines, A. Mahdavi, M. J. Geller +3
Using a large redshift survey covering 95 square degrees, we demonstrate that the infall region of Abell 2199 contains Abell 2197, one or two X-ray emitting groups, and up to five…
The Orbital Structure of Dark Matter Halos with Gas
Andisheh Mahdavi
With the success of the Chandra and XMM missions and the maturation of gravitational lensing techniques, powerful constraints on the orbital structure of cluster dark matter halos…
The RASSCALS: An X-ray and Optical Study of 260 Galaxy Groups
A. Mahdavi, H. Boehringer, M. J. Geller +1
We describe the ROSAT All-Sky Survey-Center for Astrophysics Loose Systems (RASSCALS), the largest X-ray and optical survey of low mass galaxy groups to date. We draw 260 groups fr…
The Cluster LX-sigma Relation Has Implications for Scale-Free Cosmologies
Andisheh Mahdavi
I show that the cluster LX-sigma relation should be sensitive to cosmologies with a scale-free power spectrum of initial density fluctuations, P(k) ~ k^n. I derive the dependence,…
The Dynamics of Poor Systems of Galaxies
A. Mahdavi, M. J. Geller, H. Boehringer +2
We assemble and observe a sample of poor galaxy systems that is suitable for testing N-body simulations of hierarchical clustering (Navarro, Frenk, & White 1997; NFW) and other dyn…