COUPP (The Chicagoland Observatory for Underground Particle Physics) employs room temperature bubble chambers to search for dark matter particle candidates. Following continuous 2011 operation of a chamber containing 4 kg of trifluoromethyl iodide (CF_3I) at the underground depth of SNOLAB at Sudbury, Canada, COUPP presently offers the best sensitivity to spin-dependent WIMP (Weakly Interacting Massive Particles)-nucleus couplings from any dark matter search. Dramatic progress in acoustic discrimination against alpha particles and the abatement of backgrounds has recently been made. With these new developments, COUPP should also lead the field in sensitivity to spin-independent couplings, following the installation of an already-commissioned 60 kg chamber at SNOLAB.
The level of maturity reached by this technique has prompted this collaboration to initiate the conceptual design of a 500 kg module. Detailed Monte Carlo simulations indicate that this chamber will have the ability to perform an exhaustive exploration of the vast supersymmetric WIMP parameter space. The design is to be based on a modest extrapolation of the systems already developed and tested for the 60 kg chamber. This award provides support to complete the design and development of COUPP-500.
Broader Impacts: The effort described will generate substantial broader impacts in the areas of education and mentoring. COUPP has a long history of commitment to providing undergraduates with laboratory research opportunities, through UC, IUSB and FNAL programs, and to the mentoring and promotion of graduate students and postdocs.