Strong Lensing Constraints on Small-Scale Linear Power

Abstract

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 models, and in conjunction with other cosmological probes, place constraints on the neutrino mass m_nu, tilt of the primordial power spectrum n, and mass of the dark matter particle m. We find n>0.94, and for a Harrison-Zeldovich spectrum, find m_nu<0.74 eV and m>5.2 keV, at 95% confidence.

Figures (2)

• Figure 1: Variance $\sigma$ on mass scale $M$. Contours depict the 68%, 90% and 95% confidence regions from lensing. The curves depict predictions for the cosmologies denoted which, unless labeled otherwise, are flat $\Lambda$CDM universes with $h=0.66$, $\Omega_{\rm M}h^2=0.15$, $\Omega_\nu=0$ and $n=1$. For the WDM models, $m$ denots the WDM mass.
• Figure 2: Likelihood of (a) tilt of primordial power spectrum, (b) neutrino mass, (c) dark matter particle mass.