Kavli Affiliate: John Belcher | Summary:We consider the problem of a rotating charged spherical shell of radius a carrying an axially symmetric distribution of charge. We give the interior and exterior solutions to this problem for arbitrary zonal dependence of the surface charge distribution and for arbitrary time dependence of the rotation rate. Surprisingly, these […]
Kavli Affiliate: Edmund Bertschinger | Summary:We present the results of a systematic search in approximately 14 years of Rossi X-ray Timing Explorer All-Sky Monitor data for evidence of periodicities not reported by Wen et al. (2006). Two variations of the commonly used Fourier analysis search method have been employed to achieve significant improvements in sensitivity. […]
Kavli Affiliate: Edmund Bertschinger | Summary:Using a generalized self-similar secondary infall model, which accounts for tidal torques acting on the halo, we analyze the velocity profiles of halos in order to gain intuition for N-body simulation results. We analytically calculate the asymptotic behavior of the internal radial and tangential kinetic energy profiles in different radial […]
Kavli Affiliate: Edmund Bertschinger | Summary:N-body simulations have revealed a wealth of information about dark matter halos however their results are largely empirical. Using analytic means, we attempt to shed light on simulation results by generalizing the self-similar secondary infall model to include tidal torque. In this first of two papers, we describe our halo […]
Kavli Affiliate: Kiyoshi Wesley Masui | Summary:A new effect is described by which primordial gravity waves leave a permanent signature in the large scale structure of the Universe. The effect occurs at second order in perturbation theory and is sensitive to the order in which perturbations on different scales are generated. We derive general forecasts […]
Kavli Affiliate: Edmund Bertschinger | Summary:Indirect detection of high-energy particles from dark matter interactions is a promising avenue for learning more about dark matter, but is hampered by the frequent coincidence of high-energy astrophysical sources of such particles with putative high-density regions of dark matter. We calculate the boost factor and gamma-ray flux from dark […]
Kavli Affiliate: Kiyoshi Wesley Masui | Summary:It is shown that 21 cm intensity mapping could be used in the near term to make cosmologically useful measurements. Large scale structure could be detected using existing radio telescopes, or using prototypes for dedicated redshift survey telescopes. This would provide a measure of the mean neutral hydrogen density, […]
Kavli Affiliate: Kiyoshi Wesley Masui | Summary:We present projected constraints on modified gravity models from the observational technique known as 21 cm intensity mapping, where cosmic structure is detected without resolving individual galaxies. The resulting map is sensitive to both BAO and weak lensing, two of the most powerful cosmological probes. It is found that […]
Kavli Affiliate: Mark Schattenburg | Summary:Low-mass pre-main sequence (PMS) stars are strong and variable X-ray emitters, as has been well established by EINSTEIN and ROSAT observatories. It was originally believed that this emission was of thermal nature and primarily originated from coronal activity (magnetically confined loops, in analogy with Solar activity) on contracting young stars. […]
Kavli Affiliate: John Belcher | Summary:Animated textures can be used to visualize the spatial structure and temporal evolution of vector fields at high spatial resolution. The animation requires two time-dependent vector fields. The first of these vector fields determines the spatial structure to be displayed. The second is a velocity field that determines the time […]