Marsfield Lecture Theatre

Kiyoshi Masui

21 cm Intensity Mapping: Large scale structure with the Green Bank Telescope -- Kiyoshi Masui Colloquium

The 21cm radio line, from the hyperfine energy splitting in neutral hydrogen, has long been a useful tool in radio astronomy for studying the local universe. More recently it has been proposed that the line might be used to study a wide range of problems at high redshift, including reionization around z=8, large scale structure and galaxy
formation around z=1, and even the initial conditions of the universe at z>10. I will describe the first attempts to use the line to study large scale structure using a method referred to as intensity mapping. Our collaboration uses the Green Bank Telescope to observe the 21cm line at
low resolution in the redshift range 0.6<z<1. With promising early results from cross correlating with the WiggleZ galaxy survey, we arenow pushing toward a completely autonomous detection.