Speaker
Ivan Padilla
(University of Toronto)
Description
SPIDER is a balloon-borne polarimeter designed to detect B-modes in the CMB at degree angular scales. Such a signal is a characteristic of early universe gravitational waves, a cornerstone prediction of inflationary theory. Hanging from a balloon at an altitude of 36 km allows the instrument to bypass 99% of the atmosphere and get an unobstructed view of the sky at 90 and 150 GHz. The multi-band nature of the experiment will help characterize galactic foregrounds, which need to be well understood before a primordial polarization signal can be extracted from the data.
During its first flight from Antarctica in January 2015, SPIDER probed 8% of the sky with 2000 polarization-sensitive bolometers. These were distributed amongst six cryogenically cooled telescopes housed in a 1300 liter liquid-helium cryostat. This massive cryostat was supported and steered by a light-weight carbon fibre structure, equipped with two sets of motors that controlled its pointing on the sky through real-time position feedback from a variety of sensors.
I will discuss the performance of the instrument over the 16 day flight and what we might learn from the dataset. I will also give a glimpse into the capabilities of the upgraded instrument, scheduled to fly in 2018.
Author
Ivan Padilla
(University of Toronto)
