3:30–4:30 am ERC 161
Eric Dahl, Northwestern University
"Scintillating Bubble Chambers"
Host: Erik Shirokoff
Moderately superheated bubble chambers have proven to be an excellent method for WIMP hunting thanks to their world-leading electron-recoil discrimination, easy scalability, and diversity of potential WIMP targets. While the PICO Collaboration continues to increase the size and sensitivity of these devices, the successes of the past decade have also enabled a new bubble chamber variant where the superheated target is also a liquid scintillator. In these Scintillating Bubble Chambers, the nuclear recoil from a WIMP interaction simultaneously nucleates a bubble and creates a flash of scintillation light. On paper, this technique combines the electron recoil discrimination of a bubble chamber with the event-by-event energy reconstruction of a scintillator. In practice, these two signals conspire to allow scintillating bubble chambers to run at much lower thresholds than can be achieved in a standard PICO chamber. Superheated noble liquids, in particular, may be completely insensitive to electron recoils even when running at thresholds as low as 100 eV. I will describe our current understanding of why scintillating bubble chambers can reach these low thresholds, review the unique dark matter and neutrino physics open to a detector capable of electron/nuclear recoil discrimination at sub-keV energies, and update our progress on the first physics-scale scintillating bubble chamber, a 10-kg argon detector now under construction at Fermilab.