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.


Recent News

Mason says, “there are so few of us, people get the impression that we are like unicorns – either non-existent or magical.” We are far from non-existent, but I find women of color to be quite magical. However, as Jesse Williams says, “Just because we’re magic, doesn’t mean we’re not real.”

  • Outreach

It’s up to you and your team to save the free world from evil forces plotting its destruction, and you have precisely 60 minutes to do it. You must find out what happened to Professor Schrödenberg, a University of Illinois physicist who disappeared after developing a top-secret quantum computer that can crack any digital-security encryption code in the world.  Unfortunately, the previous groups of special agents assigned to the case disappeared while investigating the very room in which you now find yourself locked up, Schrödenberg’s secret lab.

LabEscape is a new science-themed escape room now open at Lincoln Square Mall in Urbana, testing the puzzle-solving skills of groups of up to six participants at a time. Escape rooms, a new form of entertainment cropping up in cities across the U.S. and around the globe, provide in-person mystery-adventure experiences that have been compared to living out a video-game or movie script. A team of participants is presented with a storyline and locked into a room with only one hour to find and decipher a sequence of interactive puzzles that will unlock the door and complete the mission. Two escape room businesses are already in operation in the area, C-U Adventures in Time and Space in Urbana and Brainstorm Escapes in Champaign.


  • Research
  • AMO/Quantum Physics
  • Condensed Matter Physics

Topological insulators, an exciting, relatively new class of materials, are capable of carrying electricity along the edge of the surface, while the bulk of the material acts as an electrical insulator. Practical applications for these materials are still mostly a matter of theory, as scientists probe their microscopic properties to better understand the fundamental physics that govern their peculiar behavior.

Using atomic quantum-simulation, an experimental technique involving finely tuned lasers and ultracold atoms about a billion times colder than room temperature, to replicate the properties of a topological insulator, a team of researchers at the University of Illinois at Urbana-Champaign has directly observed for the first time the protected boundary state (the topological soliton state) of the topological insulator trans-polyacetylene. The transport properties of this organic polymer are typical of topological insulators and of the Su-Schrieffer-Heeger (SSH) model.

Physics graduate students Eric Meier and Fangzhao Alex An, working with Professor Bryce Gadway, developed a new experimental method, an engineered approach that allows the team to probe quantum transport phenomena.

  • Research
  • Astrophysics/Cosmology

In its search for extrasolar planets, the Kepler space telescope looks for stars whose light flux periodically dims, signaling the passing of an orbiting planet in front of the star. But the timing and duration of diminished light flux episodes Kepler detected coming from KIC 846852, known as Tabby’s star, are a mystery. These dimming events vary in magnitude and don’t occur at regular intervals, making an orbiting planet an unlikely explanation. The source of these unusual dimming events is the subject of intense speculation. Suggestions from astronomers, astrophysicists, and amateur stargazers have ranged from asteroid belts to alien activity.  

Now a team of scientists at the University of Illinois at Urbana-Champaign—physics graduate student Mohammed Sheikh, working with Professors Karin Dahmen and Richard Weaver—proffer an entirely novel solution to the Tabby’s star puzzle. They suggest the luminosity variations may be intrinsic to the star itself.