2026/09/24(Thu) 14:00 -15:30 七樓研討室 7F, P7A Seminar Room
Title
The PICO Bubble Chamber Search for WIMP Dark Matter
Speaker
Dr. William Woodley (University of Alberta, Canada)Abstract
Despite an abundance of cosmological evidence for its existence from the past century, the nature of dark matter remains one of the outstanding questions in modern physics. Direct-detection experiments seek to understand this nature by observing interactions of dark matter particles with ordinary matter. The PICO experiment is a direct detection experiment that searches for Weakly-Interacting Massive Particles (WIMPs) using bubble chambers.
PICO detectors are filled with superheated C3F8, making them particularly sensitive to spin-dependent interactions between WIMPs and protons, a region of parameter space where PICO has achieved some of the world's strongest constraints. The thermodynamic threshold of the bubble chamber can also be tuned to efficiently detect nuclear recoils while remaining largely insensitive to electron recoil backgrounds from gammas. The PICO-40L bubble chamber is currently operating 2 km underground at SNOLAB in Sudbury, Ontario, Canada. Its design acts as a proof-of-concept for the next generation PICO-500 detector, a 260-L bubble chamber with a projected ton-year exposure currently in the assembly phase.
This talk will introduce the principles behind PICO's bubble chamber technology and its approach to controlling backgrounds, and will present preliminary data from the PICO-40L experiment as well as the status of the PICO-500 detector.
Language
演講語言 (Language): in Mandarin