WIDG Seminar: Sumita Ghosh, Yale, “Searching for Millicharged Particles Using Optically Levitated Microspheres”

Event time: 
Thursday, September 20, 2018 - 12:00pm to 1:00pm
Wright Lab - Connector (EAL), WLC-245 See map
270 Whitney Avenue
New Haven, CT 06511
Event description: 

Standard searches for dark matter attempt to identify interactions of dark matter particles in terrestrial detectors; a complementary search would involve looking for “dark forces,” i.e. new forces under which dark matter particles interact. In certain models of such forces, dark matter particles can obtain a tiny electric charges. Such stable “millicharged” particles can then be searched for bound in matter. We use an optical trap to measure the response to an applied electric field on a charge-neutral object that may contain such particles. This experiment has a fractional electron number sensitivity of down to 10^−4 electrons/ √ Hz regardless of the mass of the millicharged particle, allowing exploration of uncharted regions of parameter space for such dark matter candidates.