PSD scientist named co-spokesperson for international science collaboration mapping remnant light from the Big Bang

April 18, 2022

This fall, the National Academy of Sciences set priorities for the field of astronomy and astrophysics in its Astro2020 decadal survey and endorsed CMB-S4—an experiment in the planning stages to map the remnant light from the Big Bang that will provide insight into the most energetic processes in the universe and reveal what drives galaxy growth. 

Jeff McMahon
Jeff McMahon, Associate Professor, Department of Astronomy & Astrophysics

CMB-S4, which comprises an ambitious set of observatories in Chile and the South Pole, has named two new co-spokespeople: Jeff McMahon, Associate Professor of Astronomy and Astrophysics at the University of Chicago, and Kevin Huffenberger, Associate Professor of Physics at Florida State University.

"CMB-S4 will transform our understanding of our universe from the absolute beginning of time through structure formation and could even discover new objects in our solar system," said McMahon, an experimentalist who has played key roles on CMB projects in Chile and at the South Pole. "I'm thrilled the collaboration entrusted me with this role, and I look forward to working with Kevin to ensure that the collaboration accomplishes all the groundbreaking science that we have spent nearly a decade planning."

CMB-S4 plans to employ 21 telescopes in the South Pole and Chilean Atacama desert to survey the sky for seven years, mapping the cosmic microwave background—light leftover from the Big Bang—to unprecedented precision. This project will enable scientists to search for signatures of gravitational waves from the dawn of time, examine the nature of dark matter and energy, map matter throughout the universe, and capture astronomical events, such as gamma-ray bursts or tidal disruption events—stars pulled apart by a black hole's gravity.

"One thing that excites me the most is that we might be able to see the signature of primordial gravitational waves, which will provide a window into the first fractions of a second after the universe began and be the highest energy physics that have ever been probed," said McMahon. "This will be a revolutionary physics measurement and provide fundamental information about how the universe began."

Formerly established in 2018, the CMB-S4 Science Collaboration now includes 390 members at 118 institutions in 19 countries and 27 U.S. States, with 23 members at UChicago. As co-spokespeople, McMahon and Huffenberger will be responsible for leading the collaboration and advancing the interests of all members of the community.

"This is a critical juncture for CMB-S4," McMahon said. "With the decadal survey, we're at this point where over the course of the next two years, we'll transition from planning a project to actually executing it."

McMahon and Huffenberger will assume their duties as co-spokespeople in July and serve a two-year term, with possible renewal up to four years. They will succeed John Carlstrom, UChicago's Subramanyan Chandrasekhar Distinguished Service Professor, and Julian Borrill, Senior Scientist at the Computational Cosmology Center at Lawrence Berkeley National Laboratory and Senior Research Physicist at Space Sciences Laboratory at UC Berkeley. 

“The science promised by CMB-S4 is simply spectacular, including unique insights into the origin of our Universe and its evolution to the present day.  We are thrilled for McMahon and Huffenberger, who have already contributed so much to the project, to lead the collaboration," said Carlstrom.