Benjamin McCall elected APS Fellow

Siv Schwink
11/14/2012 12:00 AM

Associate Professor Benjamin McCall has been elected a Fellow of the American Physical Society “for integrative studies of the simplest polyatomic molecule (H3+), including its dissociative recombination, proton-swapping reaction with H2, and astronomical observations and modeling; and for the development of high-sensitivity, high-precision methods for molecular ion spectroscopy."

McCall has built an exciting research program in the emerging field of astrochemistry. His team’s work probes the network of chemical reactions responsible for the formation of most molecules in the universe and so has profound implications for our understanding of the origins of the universe and life.
 
McCall’s research group has developed new highly sensitive techniques in high-resolution laser spectroscopy to study astronomically important molecular ions in the gas phase. This laboratory work generates spectroscopic “fingerprints” of the highly reactive (and therefore short-lived) ions at low temperatures.
 
McCall and his team are then able to use powerful ground-based and space-based telescopes to search for these spectra to determine the concentration of these molecular ions in the interstellar medium and in interstellar clouds, where low densities and ultracold temperatures slow the unfolding of chemical reactions. Finally, McCall and his team interpret the concentrations using models based on chemical kinetics to characterize the chemical and physical conditions in the interstellar clouds.
 
The McCall research group’s studies of the chemical reaction of H3+ with H2 (which interchanges identical protons subject to the conservation of nuclear spin angular momentum) and the recombination of H3+ with electrons (a key process in interstellar chemistry) has shed new light on the composition of interstellar environments.
 
Department Head and Professor of Physics Dale Van Harlingen said, “Ben is an exceptional scholar whose pioneering work is truly interdisciplinary—at the intersection of chemistry, astronomy, and physics. We are happy to have him as an affiliate in the Department of Physics—the research by his group in observational molecular astronomy, the chemistry of fundamental reactive ion species, and laboratory detection of molecules of astronomical importance couples well to our growing interest in the emerging fields of astrobiology and astrochemistry."
 
McCall earned a bachelor of science in chemistry from the California Institute of Technology in 1995 and a joint Ph.D. in chemistry and astronomy & astrophysics from the University of Chicago in 2001. He then worked as a postdoctoral fellow at the University of California at Berkeley before joining the University of Illinois faculty as an assistant professor in 2004. He holds appointments in the Departments of Chemistry, Astronomy, and Physics.
 
McCall is the recipient of many honors. Among these, he was named University Scholar (2011), received the Sloan Research Fellowship from the Alfred P. Sloan Foundation (2009), the Coblentz Award from the Coblentz Society (2009), the Cottrell Scholar Award from the Research Corporation (2007), the David and Lucile Packard Fellowship (2006), the Presidential Early Career Award for Scientists and Engineers (2005), and a National Science Foundation CAREER award (2005).
 
Election to fellowship in the American Physical Society is limited to no more than one-half of one percent of the Society's membership and is conferred following a rigorous, peer-reviewed selection process.  Fellows are recognized internationally for their outstanding contributions to physics.
 
See McCall’s extensive list of publications here.

 

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