Physics & Astronomy Colloquium: Dr. Andre Frankenthal, Princeton University

Squeezing the proverbial lemon: How to probe “new” physics with “old” particle accelerators

Despite the remarkable evolution in accelerator technology over the past century, culminating with the start of Large Hadron Collider (LHC) operations at CERN in 2009, direct experimental evidence for physics beyond the Standard Model remains elusive. In this talk, I will demonstrate that existing particle accelerators can be used in creative ways to probe an important area of particle physics, namely that of low-mass and rare phenomena. I will first show how the intense beam of protons created by the LHC can be leveraged to observe ultra-rare processes like the suppressed decays of light particles. I will then argue how this newfound access to such rare decays constitutes a valuable tool in the search for low-mass dark matter (DM) production at the LHC. Models of DM with sub-GeV masses are compelling because of their connection to astronomical and cosmological observations, and thus facilitating their study with accelerator-based experiments is an important milestone. Finally, I will present prospects for improving the experimental sensitivity to such DM models featuring even lower masses, in part by relying on an entirely separate 90s-era Italian accelerator facility called DAFNE.