O.M. Stewart Colloquium Series

Thursday, February 16, 2017 4:00pm

Room 126, Physics Bldg.


Prof. Daniel Jacobs, Arizona State University, presents, "HERA: the Next Generation 21cm Reionization Array," Thursday, Feb. 16, Room 126, Physics Building. Refreshments will be served at 3:30 p.m. in 223A Physics Library,

Prof. Daniel Jacobs, ASU

The first 500 million years after the big bang is one of the last unexplored periods of cosmic history. During that time Hydrogen combined from the primordial plasma and condensed into the first stars and black holes which soon ionized the remaining hydrogen.  This rich history is accessible via the hydrogen 21cm line which can theoretically trace out structure in three dimensions before, during, and after reionization.  Observations by new low frequency radio telescopes like the Hydrogen Epoch of Reionization Array will provide a unique view of the first stars and galaxies complementary to deep observations of the most distant galaxies; there is also the opportunity to tighten constraints on cosmological parameters. HERA is a second generation 21cm reionization telescope currently under construction in South Africa. The experimental challenge is in discriminating faint background from bright foreground; to meet this challenge we are developing new methods for precision instrument calibration and analysis. In this talk we’ll learn about some of the early 21cm results, the HERA science goals, some instrumental and analysis challenges, and look briefly to the future.