We measure the cross-correlation of cosmic microwave background (CMB) lensing convergence maps derived from Atacama Cosmology Telescope data with galaxy lensing convergence maps as measured by the Canada-France-Hawaii Telescope Stripe 82 Survey. The CMB-galaxy lensing cross power spectrum is measured for the first time with a significance of 4.2 σ , which corresponds to a 12% constraint on the amplitude of density fluctuations at redshifts ∼0.9 . With upcoming improved lensing data, this novel type of measurement will become a powerful cosmological probe, providing a precise measurement of the mass distribution at intermediate redshifts and serving as a calibrator for systematic biases in weak lensing measurements.
Physical Review D
- Pub Date:
- March 2015
- Gravitational lenses and luminous arcs;
- Background radiations;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- 11 pages, 7 figures. Submitted to PRD. Updates to lensing maps and analysis pipeline, with revised results, increased significance