Department of Astronomy Center for Radiophysics & Space Research

Michael was an Astronomy graduate student at Cornell from 2011 to 2016. He worked with Professors Martha Haynes and Riccardo Giovanelli on the ALFALFA survey. This was a blind survey covering 1/6th of the sky with the 305 m Arecibo radio-telescope in Puerto Rico that detected approximately 30,000 galaxies in the nearby Universe through the 21 cm radio emission of their neutral hydrogen gas. Neutral hydrogen is a key component of the Universe and of galaxies. When gas is accreted onto a galaxy it must pass through the neutral phase before condensing to form molecular gas and the dense clouds from which stars can eventually form. In this way the neutral hydrogen content of a galaxy gives a measure of the available gas reservoir that the galaxy has to form stars in the long term.

Michael's PhD research primarily focused on the statistical aspects of the survey. In particular he used the properties of the galaxy population detected by ALFALFA to make predictions of how the systematic effects of source confusion (the blurring together of adjacent sources) will impact future, much deeper, surveys of neutral hydrogen with the Square Kilometre Array and its precursor facilities. He also investigated the effects of galaxy environment on the neutral hydrogen content of the ALFALFA galaxies by calculating the mass function (the relative abundance of galaxies of different masses) in an array of environments defined by the density of their neighbouring galaxies in the Sloan Digital Sky Survey and the 2MASS Redshift Survey. In June 2016 Michael moved to Granada, Spain for a post-doctoral research position with Lourdes Verdes-Montenegro at the Instituto de Astrofísica de Andalucía.