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Updated: Apr 13, 2026

Digital Inline Holographic Microscopy DIHM of Weakly-scattering Subjects
Published on: February 8, 2014
Evidence of lensing of the cosmic microwave background by dark matter halos
Mathew Madhavacheril1, Neelima Sehgal1, Rupert Allison2
1Physics and Astronomy Department, Stony Brook University, Stony Brook, New York 11794, USA.
Abstract:
We present evidence of the gravitational lensing of the cosmic microwave background by 10(13) solar mass dark matter halos. Lensing convergence maps from the Atacama Cosmology Telescope Polarimeter (ACTPol) are stacked at the positions of around 12 000 optically selected CMASS galaxies from the SDSS-III/BOSS survey. The mean lensing signal is consistent with simulated dark matter halo profiles and is favored over a null signal at 3.2σ significance. This result demonstrates the potential of microwave background lensing to probe the dark matter distribution in galaxy group and galaxy cluster halos.
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