A host of astrophysical and cosmological measurements have conclusively established that over 85% of all matter in the Universe is dark matter. Understanding the nature of dark matter is one of the greatest challenges of modern physics and is of paramount importance in understanding the origin and structure of the universe. A theoretically well-motivated possibility is that the dark matter consists of ultralight fields, corresponding to particles of very low mass. The mass-energy associated with dark matter is then primarily stored in oscillations of the dark matter field or in localized defects. If the dark matter takes this form, then instead of being bathed in a uniform dark matter flux, terrestrial detectors will witness transient events when the Earth passes through a dark matter clump or a kind of domain wall such as is found in a magnetized material such as nickel. This award provides support to operate, expand, and significantly upgrade a network of geographically separated, time-synchronized atomic magnetometers to search for correlated transient signals heralding new physics.
Both institutions have a strong history of diversity, with CSU - East Bay being the most diverse university in the continental United States and Oberlin College being the first college to admit African American students and women in a co-educational setting on a regular basis. The proposed research programs are at the vanguard of attracting and retaining women and underrepresented minority physicists.
The Global Network of Optical Magnetometers to search for Exotic physics (GNOME) is sensitive to nuclear and electron spin couplings to various exotic particles and fields. To date, no such search for transient spin-dependent interactions has ever been carried out, making the proposed research a completely novel experimental window on new physics. In addition to carrying out a dedicated long-term search using the existing GNOME during the first year of the grant, the GNOME will be upgraded in order to dramatically improve its sensitivity.
