Measurement of a Cosmographic Distance Ratio with Galaxy and CMB Lensing

Kavli Affiliate: Blake Sherwin

| First 5 Authors: Hironao Miyatake, Mathew S. Madhavacheril, Neelima Sehgal, An┼że Slosar, David N. Spergel

| Summary:

We measure the gravitational lensing shear signal around dark matter halos
hosting CMASS galaxies using light sources at $zsim 1$ (background galaxies)
and at the surface of last scattering at $zsim 1100$ (the cosmic microwave
background). The galaxy shear measurement uses data from the CFHTLenS survey,
and the microwave background shear measurement uses data from the {it Planck}
satellite. The ratio of shears from these cross-correlations provides a purely
geometric distance measurement across the longest possible cosmological lever
arm. This is because the matter distribution around the halos, including
uncertainties in galaxy bias and systematic errors such as miscentering,
cancels in the ratio for halos in thin redshift slices. We measure this
distance ratio in three different redshift slices of the CMASS sample, and
combine them to obtain a $17%$ measurement of the distance ratio,
$r=0.390^{+0.070}_{-0.062}$ at an effective redshift of $z=0.53$. This is
consistent with the predicted ratio from the {it Planck} best-fit $Lambda$CDM
cosmology of $r=0.419$.

| Search Query: ArXiv Query: search_query=au:”Blake Sherwin”&id_list=&start=0&max_results=10

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