Particle and Astroparticle Physics Seminar

Dark Matter Searches with PICO Bubble Chambers

Ubi Wichoski

Université de Montréal

There is plenty of evidence for the existence of dark matter. In fact, observations indicate that there is approximately 5 times more dark matter than regular matter in the Universe. However, the nature of dark matter is still unknown as all the evidence is purely gravitational. Notwithstanding, there is strong theoretical motivation towards dark matter being made of weakly interacting massive particles (WIMPs). Spiral galaxies like the Milky-Way are believed to be immersed in a halo of dark matter. The PICO Collaboration searches for dark matter through the direct detection of WIMPs in our Galaxy via dark matter spin-dependent and spin independent interactions with ordinary matter (specifically 19F nuclei). In this talk, I will briefly review the evidence for dark matter; discuss the motivation for the direct detection; give an overview of the PICO experiment; discuss the superheated liquid technique and report on the status of the experiment and on future plans.