Bradford A. Benson

Associate Professor

Bradford A. Benson
ERC 589
(773) 702-6452


PhD, Stanford University, 2004

Research Fields

  • Cosmology
  • Extragalactic Astronomy and Astrophysics
  • Particle and High Energy Astronomy and Astrophysics

Research Groups

  • Joint Dark Energy Survey-South Pole Telescope Group
  • South Pole Telescope Group

Scientific Projects


  • Daniel Dutcher (graduate/Physics)
  • Zhoadi Pan (graduate/Physics)
  • Joshua Sobrin (graduate/Physics)



I am an experimental cosmologist, who uses measurements of the cosmic microwave background (CMB) and clusters of galaxies to constrain cosmology, including the physics of the Big Bang, dark energy, and neutrinos. I work on mm-wavelength detectors and instrumentation, and have had a leading role in the development of multiple cameras for the South Pole Telescope (SPT), including the currently operating SPT-3G camera. In 2018, SPT-3G began a 5-year, 1500 sq. deg. survey that is poised to make important contributions to fundamental physics, including world-leading constraints on inflationary gravitational waves from a joint analysis of data from SPT-3G and BICEP/Keck, and two independent measurements of the sum of neutrino masses from CMB lensing and galaxy clusters, which will be further improved with joint analyses with the Dark Energy Survey (DES). I am co-lead of the SPT galaxy cluster working group, which is currently focused on combining SPT and DES measurements to place new constraints on dark energy via the growth of structure. Finally, I am working on the development of the next-generation CMB-S4 project, which will have ~20x more detectors than SPT-3G and is expected to improve CMB-based constraints by over an order of magnitude compared to current constraints.

News & Highlights