Calibration of the PICO-0.1 bubble chamber and development of coated inner vessels for dark matter search

Abstract

The detection of dark matter is one of the biggest challenges in modern physics. The PICO experiment aims for the direct detection of Weakly Interacting Massive Particles (WIMPs) with bubble chambers. In this thesis, results from calibrations of the PICO-0.1 test chamber is presented. Calibrations were performed at the Tandem Van de Graaff facility of the Université de Montréal. Monoenergetic neutrons were produced from the 51V(p,n)51Cr reaction with a 1.6 MeV proton beam. Two 3He neutron counters used during calibrations for neutron flux normalization were also calibrated. This result is contributing in improving Monte Carlo simulations of PICO-0.1. Finally, preliminary work was done toward the use of new inner vessel materials with coated surfaces for bubble chambers. A Condensation Bubble Chambers (CBCs) was used as a test-bench. Progress has been made toward the usability of Poly-methyl-methacrylate vessels, but more work is needed to solve spontaneous wall nucleation problems.