Exploring short gamma-ray bursts as gravitational-wave standard sirens (2009)
Nissanke, Samaya, Hughes, Scott A., Holz, Daniel E., Dalal, Neal, Sievers, Jonathan L.
Recent observations support the hypothesis that a large fraction of "short-hard" gamma-ray bursts (SHBs) are associated with compact binary inspiral. Since gravitational-wave (GW) measurements of...
Strong gravitational lensing probes of the particle nature of dark matter (2009)
Moustakas, Leonidas A., Abazajian, Kevork, Benson, Andrew, Bolton, Adam S., Bullock, James S., Chen, Jacqueline, ...
There is a vast menagerie of plausible candidates for the constituents of dark matter, both within and beyond extensions of the Standard Model of particle physics. Each of these candidates may have...
Oguri, Masamune, Hennawi, Joseph F., Gladders, Michael D., Dahle, Haakon, Natarajan, Priyamvada, Dalal, Neal, ...
We derive radial mass profiles of four strong lensing selected clusters which show prominent giant arcs (Abell 1703, SDSS J1446+3032, SDSS J1531+3414, and SDSS J2111-0115), by combining detailed...
Halo Assembly Bias in Hierarchical Structure Formation (2008)
Dalal, Neal, White, Martin, Bond, J. Richard, Shirokov, Alexander
We investigate the origin of halo assembly bias, the dependence of halo clustering on assembly history. We relate halo assembly to peak properties measured in the Lagrangian space of the initial...
A new survey for giant arcs (2008)
Hennawi, Joseph F., Gladders, Michael D., Oguri, Masamune, Dalal, Neal, Koester, Benjamin, Natarajan, Priyamvada, ...
We report on the first results of an imaging survey to detect strong gravitational lensing targeting the richest clusters selected from the photometric data of the Sloan Digital Sky Survey (SDSS)...
Dalal, Neal, Doré, Olivier, Huterer, Dragan, Shirokov, Alexander
We study the effect of primordial nongaussianity on large-scale structure, focusing upon the most massive virialized objects. Using analytic arguments and N-body simulations, we calculate the mass...
A New Survey for Giant Arcs (2006)
Hennawi, Joseph F., Gladders, Michael D., Oguri, Masamune, Dalal, Neal, Koester, Benjamin, Natarajan, Priyamvada, ...
We report on the first results of an imaging survey to detect strong gravitational lensing targeting the richest clusters selected from the photometric data of the Sloan Digital Sky Survey (SDSS)...
Astrometric Perturbations in Substructure Lensing (2006)
Chen, Jacqueline, Rozo, Eduardo, Dalal, Neal, Taylor, James E.
In recent years, gravitational lensing has been used as a means to detect substructure in galaxy-sized halos, via anomalous flux ratios in quadruply-imaged lenses. In addition to causing anomalous...
Short GRB and binary black hole standard sirens as a probe of dark energy (2006)
Dalal, Neal, Holz, Daniel E., Hughes, Scott A., Jain, Bhuvnesh
Observations of the gravitational radiation from well-localized, inspiraling compact object binaries can measure absolute source distances with high accuracy. When coupled with an independent...
The impact of lens galaxy environments on the image separation distribution (2005)
Oguri, Masamune, Keeton, Charles R., Dalal, Neal
We study the impact of lens galaxy environments on the image separation distribution of lensed quasars. We account for both environmental convergence and shear, using a joint distribution derived...
Characterizing the Cluster Lens Population (2005)
Hennawi, Joseph F., Dalal, Neal, Bode, Paul, Ostriker, Jeremiah P.
We present a detailed investigation into which properties of CDM halos make them effective strong gravitational lenses. Strong lensing cross sections of 878 clusters from an N-body simulation are...
Statistics of Quasars Multiply Imaged by Galaxy Clusters (2005)
Hennawi, Joseph F., Dalal, Neal, Bode, Paul
We compute the expected number of quasars multiply imaged by cluster size dark halos for current wide field quasar surveys by carrying out a large ensemble of ray tracing simulations through clusters...
What are the environments of lens galaxies? (2004)
Using measured tangential shear profiles and number counts of massive elliptical galaxies, the halo occupation distribution of strong lensing galaxies is constrained. The resulting HOD is then used...
Noise in strong lensing cosmography (2004)
Dalal, Neal, Hennawi, Joseph, Bode, Paul
Giant arcs in strong lensing galaxy clusters can provide a purely geometric determination of cosmological parameters, such as the dark energy density and equation of state. We investigate sources of...
Revisiting the Magnification of Type Ia Supernovae with SDSS (2004)
We cross-correlate the sample of Type Ia supernovae from Riess et al. (2004) with the SDSS DR2 photometric galaxy catalogue. In contrast to recent work, we find no detectable correlation between...
(Lack of) lensing constraints on cluster dark matter profiles (2003)
Dalal, Neal, Keeton, Charles R.
Using stellar dynamics and strong gravitational lensing as complementary probes, Sand et al. (2002, 2003) have recently claimed strong evidence for shallow dark matter density profiles in several...
Statistics of Giant Arcs in Galaxy Clusters (2003)
Dalal, Neal, Holder, Gilbert, Hennawi, Joseph
We study the expected properties and statistics of giant arcs produced by galaxy clusters in a LambdaCDM universe and investigate how the characteristics of CDM clusters determine the properties of...
Bringing closure to microlensing mass measurement (2002)
Dalal, Neal, Lane, Benjamin F.
Interferometers offer multiple methods for studying microlensing events and determining the properties of the lenses. We investigate the study of microlensing events with optical interferometers,...
Corrective lenses for high redshift supernovae (2002)
Dalal, Neal, Holz, Daniel E., Chen, Xuelei, Frieman, Joshua A.
Weak lensing of high-redshift Type Ia supernovae induces an external dispersion in their observed standard candle brightnesses, comparable in magnitude to the intrinsic dispersion for redshifts z>1....
Strong Lensing Constraints on Small-Scale Linear Power (2002)
Dalal, Neal, Kochanek, Christopher S.
We place limits on the linear power spectrum on small scales (k > 50 h/Mpc) using measurements of substructure in gravitational lens galaxies. We find excellent agreement with the simplest LambdaCDM...
Implications of Neutron Decoupling in Short Gamma Ray Bursts (2001)
Roughly half of the observed gamma-ray bursts (GRBs) may arise from the shocking of an ultra-relativistic shell of protons with the interstellar medium (ISM). Any neutrons originally present in the...
Testing the Cosmic Coincidence Problem and the Nature of Dark Energy (2001)
Dalal, Neal, Abazajian, Kevork, Jenkins, Elizabeth, Manohar, Aneesh V.
Dark energy models which alter the relative scaling behavior of dark energy and matter could provide a natural solution to the cosmic coincidence problem - why the densities of dark energy and dark...
The difficulty in using orphan afterglows to measure gamma-ray burst beaming (2001)
Dalal, Neal, Griest, Kim, Pruet, Jason
If gamma-ray burst (GRB) emission is strongly collimated then GRBs occur throughout the Universe at a rate much higher than is detected. Since the emission from the optical afterglow is thought to be...
Astrometric imaging of crowded stellar fields with only two SIM pointings (2001)
The Space Interferometry Mission (SIM) will observe sources in crowded fields. Recent work has shown that source crowding can induce significant positional errors in SIM's astrometric measurements,...
Testing the Cosmic Coincidence Problem and the Nature of Dark Energy (2001)
Abazajian, Kevork, Dalal, Neal, Jenkins, Elizabeth, Manohar, Aneesh V.
Magnification relations in gravitational lensing via multidimensional residue integrals (2000)
Dalal, Neal, Rabin, Jeffrey M.
We investigate the so-called magnification relations of gravitational lensing models. We show that multidimensional residue integrals provide a simple explanation for the existence of these...
In light of recent evidence suggesting a nonzero present-day cosmological constant, Adams, Mbonye, & Laughlin (1999) have considered the evolution of black holes in the presence of vacuum energy....
Astrometric Microlensing as a Method of Discovering and Characterizing Extra-Solar Planets (1998)
Safizadeh, Neda, Dalal, Neal, Griest, Kim
We introduce a new method of searching for and characterizing extra-solar planets. We show that by monitoring the center-of-light motion of microlensing alerts using the next generation of high...