Speaker
Description
The PICO collaboration operates bubble chambers to search for WIMP dark matter, leveraging the excellent gamma rejection and long live fractions enabled by operating at a lower degree of superheat than the bubble chambers of the 1960s. This advancement allows for significantly improved background rejection while maintaining sensitivity to nuclear recoils. Located at the SNOLAB underground laboratory, these detectors use fluorinated target fluids optimized for probing spin-dependent WIMP-proton interactions. Previous experiments, PICO-2L and PICO-60, set the world’s strongest constraints on spin-dependent WIMP-proton scattering. The next-generation detector, PICO-40L, is now fully operational and actively collecting physics data. Its superheated C3F8 target provides an ideal medium to achieve world-leading sensitivity in this search. This talk will provide an overview of the detector design, analysis strategy, and initial physics results. Looking ahead, PICO-500, a 250-liter chamber currently in development, is expected to begin commissioning in 2026, further advancing the search for dark matter.