POLARBEAR: results of the first season and future prospects for CMB polarisation measurements
Over the last two decades cosmology has been transformed from a data-starved to a data-driven, high precision science. This transformation happened thanks to improved observational techniques, allowing to collect progressively bigger and more powerful data sets. Studies of the Cosmic Microwave Background (CMB) anisotropies have played, and continue on doing so, a particularly important and impactful role in this process. The huge data sets produced by recent CMB experiments pose new challenges for the field due to their volumes and complexity. Its successful resolution requires combining mathematical, statistical and computational methods all of which form a keystone of the modern CMB data analysis.
As the sensitivity of the instruments has approached the level of the B-modes signal, its measurements have become of major interest in cosmology. At the forefront in this quest, POLARBEAR is a ground-based telescope located in the Atacama desert (Chile), at nearly 5200 m of altitude. Using 1274 polarization sensitive bolometers in combination with a relatively high resolution (3.5 arcmin), POLARBEAR has been observing small CMB patches (3x3 deg2) at 150 GHz since 2012.
In this talk, after introducing the POLARBEAR instrument, I will detail the data analysis of its first year data set, as well as the first round of the scientific results, highlighting my own contributions to various stages of the project.
I will then describe how the POLARBEAR program will be upgraded very quickly with two forthcoming reincarnations of the current instrument, which are referred to as POLARBEAR-2 and SIMONS ARRAY.