Sudeep Das
(UC Berkeley / LBNL)
Abstract:
Over the coming decade, tiny fluctuations in temperature and
polarization of the Cosmic Microwave Background (CMB) will be mapped
with unprecedented resolution. The Planck Surveyor, the Atacama
Cosmology Telescope (ACT), and the South Pole Telescope (SPT) are
already making great advances. In a few years, high resolution
polarization experiments, such as PolarBear, ACTPol, and SPTPol will
be in full swing. While these new arc-minute resolution observations
will continue to help constrain the physics of the early universe,
they will also be unique in a new way - they will allow us to measure
the gravitational lensing of the CMB, i.e., the deflection of CMB
photons by intervening large scale structure. CMB lensing will probe
the growth of structure over cosmic time, helping constrain the total
mass of neutrinos and the behavior of dark energy. In the first part
of the talk, I will review the recent progress made with ACT, a
powerful tool with new capabilities. In the second part, I will
discuss the scientific potential of the CMB lensing signal, its first
detection, and its various applications in cross-correlation with
other datasets. Finally, I will discuss the upcoming polarized
counterpart of ACT --- the ACTPol project, which will have sixteen
times better mapping speed than ACT, and will be a premier CMB lensing
experiment. I will describe our plans to extract different flavors of
science from the ACTPol data, including the cross-correlations with
optical lensing and galaxy surveys, such as SDSS, BOSS, DES and LSST.