Speaker
Tobias Marriage
(Johns Hopkins)
Description
We are beginning a survey to provide a robust detection and characterization of the imprint of inflationary gravitational radiation in the CMB polarization (the so-called "B modes"). The same polarization measurement will provide the ultimate CMB-based cosmic-variance-limited measurement of the optical depth to reionization. When combined with CMB temperature, lensing and Baryon Acoustic Oscillation data, the optical depth measurement will yield twofold improvements on cosmology-based estimates of the sum of the neutrino masses. To carry out the survey we have built the Cosmology Large Angular Scale Surveyor (CLASS), which is an array of millimeter-wave polarimeters sited at 5200 m in the Atacama Desert. Unique in the field of CMB polarization measurements, CLASS is especially designed to survey 70% of the sky at four frequencies and recover the CMB polarization on all angular scales relevant to inflation and reionization. In this talk I will give an overview of CLASS and discuss progress to date.
Primary author
Tobias Marriage
(Johns Hopkins)