Description:

An abundance of evidence suggests that most of the Universe is composed of matter that cannot be seen, called dark matter. Experiments around the world are attempting to directly detect rare dark matter collisions, such as the Super Cryogenic Dark Matter Search (SuperCDMS) that operated germanium crystals at tens of mK to measure ionization and phonon energy. The Low Ionization Threshold Experiment (CDMSlite) was a unique mode of operating the SuperCDMS detectors that utilized Neganov-Trofimov-Luke gain to amplify the ionization signal. This amplification lead to improved energy resolution and lower threshold, but at the expense of background rejection. Since the properties of dark matter are unknown, efforts have been made to explore a wide range of possible masses and interaction cross-sections. For the latter, experiments can increase exposure by scaling up the detector mass and running longer, but to search for low-mass dark matter (<1 GeV), new technologies and analysis techniques need to be developed. Typically, direct detection experiments assume dark matter scatters elastically off the nuclei in the detector. However, recent theories about the inelastic collision of dark matter with a nucleus have emerged. I will explain how inelastic dark matter collisions can manifest in the detector and will present a re-analysis of the most recent CDMSlite data using a profile likelihood to search for low-mass dark matter via inelastic scattering channels.

Seminar Speaker: Dan Jardin, Southern Methodist University

Keywords: Physics, Astronomy, HEP