Associate Professor of Astronomy
Professor Cohen has particular expertise in X-ray spectroscopy and modeling of hot stars and laboratory plasmas, radiation-driven stellar winds, and stellar X-ray emission. He offers courses in modern astrophysics, stellar astrophysics, and the interstellar medium.
Cohen led a team of astronomers and student researchers at Swarthmore College that discovered a new star, a previously unknown binary companion to the bright star beta Crucis, in the Southern Cross. Their discovery was announced in January 2007 at the American Astronomical Society meeting in Seattle. The companion star was discovered accidentally while the research team was using the orbiting Chandra X-ray Observatory to study the x-rays emitted by beta Crucis itself.
In 2012, Cohen and Associate Professor of Astronomy Eric Jensen contributed to the discovery of two planets dubbed KELT-1b and KELT-2Ab using the campus' observatory.
Professor Cohen received his B.A. from Harvard University and his Ph.D. from the University of Wisconsin.