12 papers
Did Zhao & Qin Solve the Apparant Conflict Beween Gravitational Lens Time Delays, Dark Matter and the Hubble Constant?
C. S. Kochanek
The solution proposed by Zhao & Qin to the apparent conflict between gravitational lens time delays, local estimates of the Hubble constant and current expectations for the structu…
Strong Lensing Constraints on Small-Scale Linear Power
Neal Dalal, Christopher S. Kochanek
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…
Detection of CDM Substructure
C. S. Kochanek, N. Dalal
The properties of multiple image gravitational lenses require a fractional surface mass density in satellites of f=0.02 (0.006 < f < 0.07 at 90% confidence) that is consistent with…
Rapid Calculation of Equatorial Rotation Curves
C. S. Kochanek
We derive a simple, fast one-dimensional integral for the equatorial rotation curve of a thin disk with surface density Sigma(R) modeled as a spheroid with axis ratio q. The result…
Dynamical Probes of The Halo Mass Function
C. S. Kochanek
We explore the relationship between the mass function of CDM halos and dynamical probes of the mass function such as the distribution of gravitational lens separations and the loca…
Evidence for Inconsistencies in Galaxy Luminosity Functions Defined by Spectral Type
C. S. Kochanek, M. A. Pahre, E. E. Falco
Galaxy morphological and spectroscopic types should be nearly independent of apparent magnitude in a local, magnitude-limited sample. Recent luminosity function surveys based on mo…