The GMRT EoR experiment: limits on polarized sky brightness at 150 MHz (2009)
Pen, Ue-Li, Chang, Tzu-Ching, Hirata, Christopher M., Peterson, Jeffrey B., Roy, Jayanta, Gupta, Yashwant, ...
The Giant Metrewave Radio Telescope (GMRT) reionization effort aims to map out the large-scale structure of the Universe during the epoch of reionization (EoR). Removal of polarized Galactic emission...
Can we discover multi-component WIMP dark matter? (2009)
Profumo, Stefano, Sigurdson, Kris, Ubaldi, Lorenzo
We address the question of whether the upcoming generation of dark matter search experiments and colliders will be able to discover if the dark matter in the Universe has more than one weakly...
Protohalo Constraints to the Resonant Annihilation of Dark Matter (2009)
Cyr-Racine, Francis-Yan, Profumo, Stefano, Sigurdson, Kris
It has recently been argued that the PAMELA, ATIC and PPB-BETS data showing an anomalous excess of high-energy cosmic ray positrons and electrons might be explained by dark matter annihilating in the...
Observing the Evolution of the Universe (2009)
Aguirre, James, Amblard, Alexandre, Ashoorioon, Amjad, Baccigalupi, Carlo, Balbi, Amedeo, Bartlett, James, ...
How did the universe evolve? The fine angular scale (l>1000) temperature and polarization anisotropies in the CMB are a Rosetta stone for understanding the evolution of the universe. Through detailed...
21 cm Intensity Mapping (2009)
Peterson, Jeffrey B., Aleksan, Roy, Ansari, Reza, Bandura, Kevin, Bond, Dick, Bunton, John, ...
Using the 21 cm line, observed all-sky and across the redshift range from 0 to 5, the large scale structure of the Universe can be mapped in three dimensions. This can be accomplished by studying...
Eternal Inflation, Bubble Collisions, and the Disintegration of the Persistence of Memory (2009)
Freivogel, Ben, Kleban, Matthew, Nicolis, Alberto, Sigurdson, Kris
We compute the probability distribution for bubble collisions in an inflating false vacuum which decays by bubble nucleation. Our analysis generalizes previous work of Guth, Garriga, and Vilenkin to...
The GMRT EoR Experiment: Limits on Polarized Sky Brightness at 150 MHz (2008)
Pen, Ue-Li, Chang, Tzu-Ching, Peterson, Jeffrey B., Roy, Jayanta, Gupta, Yashwant, Hirata, Christopher M., ...
The GMRT reionization effort aims to map out the large scale structure of the Universe during the epoch of reionization (EoR). Removal of polarized Galactic emission is a difficult part of any 21 cm...
Cosmic 21-cm Fluctuations as a Probe of Fundamental Physics (2007)
Kleban, Matthew, Sigurdson, Kris, Swanson, Ian
Fluctuations in high-redshift cosmic 21-cm radiation provide a new window for observing unconventional effects of high-energy physics in the primordial spectrum of density perturbations. In scenarios...
Profumo, Stefano, Sigurdson, Kris
We carry out a model independent study of resonant photon scattering off dark matter (DM) particles. The DM particle chi1 can feature an electric or magnetic transition dipole moment which couples it...
The Shadow of Dark Matter (2006)
Profumo, Stefano, Sigurdson, Kris
We carry out a model independent study of resonant photon scattering off dark matter (DM) particles. The DM particle chi_1 can feature an electric or magnetic transition dipole moment which couples...
Measuring the Primordial Deuterium Abundance during the Cosmic Dark Ages (2006)
Sigurdson, Kris, Furlanetto, Steven R.
We discuss how measurements of fluctuations in the absorption of cosmic microwave background photons by neutral gas at redshifts z[approximate]7–200 could reveal the primordial deuterium abundance...
What Mass Are the Smallest Protohalos? (2006)
Profumo, Stefano, Sigurdson, Kris, Kamionkowski, Marc
We calculate the kinetic-decoupling temperature for weakly interacting massive particles (WIMPs) in supersymmetric (SUSY) and extra dimensional models that can account for the cold-dark-matter...
The Spin-Resolved Atomic Velocity Distribution and 21-cm Line Profile of Dark-Age Gas (2006)
Hirata, Christopher M., Sigurdson, Kris
The 21-cm hyperfine line of atomic hydrogen (HI) is a promising probe of the cosmic dark ages. In past treatments of 21-cm radiation it was assumed the hyperfine level populations of HI could be...
Cosmological signatures of interacting neutrinos (2006)
Bell, Nicole F., Pierpaoli, Elena, Sigurdson, Kris
We investigate signatures of neutrino scattering in the cosmic microwave background (CMB) and matter power spectra, and the extent to which present cosmological data can distinguish between a...
What mass are the smallest protohalos? (2006)
Profumo, Stefano, Sigurdson, Kris, Kamionkowski, Marc
We calculate the kinetic-decoupling temperature for weakly interacting massive particles (WIMPs) in supersymmetric (SUSY) and universal-extra-dimension (UED) models that can account for the...
Variations on the standard model of the universe [microform]. (2006)
University Microfilms order no. 31-97324.
Sigurdson, Kris, Cooray, Asantha
We propose a new method for removing gravitational lensing from maps of cosmic microwave background (CMB) polarization anisotropies. Using observations of anisotropies or structures in the cosmic 21...
Cosmological Signatures of Interacting Neutrinos (2005)
Bell, Nicole F., Pierpaoli, Elena, Sigurdson, Kris
We investigate signatures of neutrino scattering in the Cosmic Microwave Background (CMB) and matter power spectra, and the extent to which present cosmological data can distinguish between a free...
Photon Regeneration from Pseudoscalars at X-ray Laser Facilities (2005)
Rabadan, Raul, Ringwald, Andreas, Sigurdson, Kris
Recently, the PVLAS collaboration has reported an anomalously large rotation of the polarization of light in the presence of a magnetic field. As a possible explanation they consider the existence of...
Variations on the standard model of the universe (2005)
In the past decade, due to compelling measurements of the angular power spectrum of the cosmic microwave background (CMB) radiation, the large-scale matter distribution, the recent acceleration of...
Variations on the standard model of the universe (2005)
In the past decade, due to compelling measurements of the angular power spectrum of the cosmic microwave background (CMB) radiation, the large-scale matter distribution, the recent acceleration of...
Measuring the Primordial Deuterium Abundance During the Cosmic Dark Ages (2005)
Sigurdson, Kris, Furlanetto, Steven R.
We discuss how measurements of fluctuations in the absorption of cosmic microwave background (CMB) photons by neutral gas during the cosmic dark ages, at redshifts z ~ 7--200, could reveal the...
Sigurdson, Kris, Cooray, Asantha
The curl (B) modes of cosmic microwave background (CMB) polarization anisotropies are a unique probe of the primordial background of inflationary gravitational waves (IGWs). Unfortunately, the B-mode...
Profumo, Stefano, Sigurdson, Kris, Ullio, Piero, Kamionkowski, Marc
We show that charged particles decaying in the early Universe can induce a scale-dependent or running spectral index in the small-scale linear and nonlinear matter power spectrum and discuss examples...
How Dark is 'Dark'? Electromagnetic Interactions in the Dark Sector (2004)
We review the physical and cosmological consequences of two possible electromagnetic couplings to the dark sector: (i) a neutral lightest dark-matter particle (LDP) with nonzero electric and/or...
Profumo, Stefano, Sigurdson, Kris, Ullio, Piero, Kamionkowski, Marc
We show that charged-particles decaying in the early Universe can induce a scale-dependent or `running' spectral index in the small-scale linear and nonlinear matter power spectrum and discuss...
Dark-matter electric and magnetic dipole moments (2004)
Sigurdson, Kris, Doran, Michael, Kurylov, Andriy, Caldwell, Robert R., Kamionkowski, Marc
We consider the consequences of a neutral dark-matter particle with a nonzero electric and/or magnetic dipole moment. Theoretical constraints, as well as constraints from direct searches, precision...
Statistical Imprints of SZ Effects in the Cosmic Microwave Background (2004)
Cooray, Asantha, Baumann, Daniel, Sigurdson, Kris
We review several aspects of the Sunyaev-Zel'dovich (SZ) effect associated with the large scale baryon distribution and its characteristic signatures in the statistics of cosmic microwave background...
Dark-Matter Electric and Magnetic Dipole Moments (2004)
Sigurdson, Kris, Doran, Michael, Kurylov, Andriy, Caldwell, Robert R., Kamionkowski, Marc
We consider the consequences of a neutral dark-matter particle with a nonzero electric and/or magnetic dipole moment. Theoretical constraints, as well as constraints from direct searches, precision...
Charged-particle decay and suppression of primordial power on small scales (2004)
Sigurdson, Kris, Kamionkowski, Marc
We study the suppression of the small-scale power spectrum due to the decay of charged matter to dark matter prior to recombination. Prior to decay, the charged particles couple to the photon-baryon...
Charged-particle decay and suppression of small-scale power (2003)
Sigurdson, Kris, Kamionkowski, Marc
We study the suppression of the small-scale power spectrum due to the decay of charged matter to dark matter prior to recombination. Prior to decay, the charged particles couple to the photon-baryon...
Spatial variation of the fine-structure parameter and the cosmic microwave background (2003)
Sigurdson, Kris, Kurylov, Andriy, Kamionkowski, Marc
We study the effects on cosmic microwave background (CMB) temperature and polarization anisotropies of spatial fluctuations of the fine-structure parameter between causally disconnected regions of...
Spatial Variation of the Fine-Structure Parameter and the Cosmic Microwave Background (2003)
Sigurdson, Kris, Kurylov, Andriy, Kamionkowski, Marc
We study the effects on cosmic microwave background (CMB) temperature and polarization anisotropies of spatial fluctuations of the fine-structure parameter between causally disconnected regions of...
The shapes of dark matter dominated dwarf spheroidal stellar density profiles (2001)
A Bayesian likelihood analysis of the stellar density profile shapes of several dark matter dominated Galactic dwarf spheroidal galaxies (dSphs) has been completed. This analysis indicates that the...
Morphing the CMB: a technique for interpolating power spectra (1999)
Sigurdson, Kris, Scott, Douglas
The confrontation of the Cosmic Microwave Background (CMB) theoretical angular power spectrum with available data often requires the calculation of large numbers of power spectra. The standard...