Sc.B., Brown University; A.M., Ph.D., Harvard University
Office: S260 Science Center; Lab: E222 Science Center
James BattatAssociate Professor of Physics
Experimental particle astrophysics including dark matter detection and precision tests of gravity with lunar laser ranging (lab website).
My research addresses two deep mysteries in physics: dark matter and dark energy. I work with the APOLLO collaboration (Apache Point Observatory Lunar Laser-ranging Operation) on tests of gravity using the Lunar Laser Ranging technique. We transmit to the Moon 100-picosecond-long pulses of green laser light from the Apache Point Observatory 3.5m telescope in New Mexico. This light reflects off of Apollo-era corner cubes on the lunar surface. With our accurate clock and single-photon detectors, we are able to determine the Earth-Moon range with millimeter precision (a part in 1012 of the total distance). These measurements provide some of the most stringent empirical constraints on gravitational physics, including tests of the strong equivalence principle, the time-evolution of Newton's Constant G, the Newtonian 1/r2 force law, and gravitomagnetism.
I also collaborate with the DRIFT experiment (Directional Recoil Information From Tracks) to search for dark matter particles using underground detectors. Astrophysical observations have revealed that the majority (~80%) of matter in the Universe falls outside of the Standard Model of particle physics. Theoretical candidates for this so-called dark matter abound, yet dark matter has not yet been directly detected in the laboratory. DRIFT seeks to measure the interaction of dark matter particles with a gas-based detector, in order to reconstruct the expected head-wind of dark matter created by the solar system's motion through the Milky Way galaxy.
I teach courses across the physics curriculum, including lecture and lab sections of PHYS107 (Principles and Applications of Mechanics), and PHYS207 (Intermediate Mechanics). As an experimentalist, I enjoy working with students in PHYS310 (Experimental Physics), and often incorporate demos and small experiments into lecture. I developed a new First-Year Seminar course called Einstein and the Dark Universe (PHYS100/ASTR110) in which students uncover the astrophysical evidence for dark matter and dark energy through analyses of archival data sets as well as their own radio telescope observations.
I find it hard to resist watching World Cup soccer games. I've done a rail slide on skis, but my wife kills me on bump runs. I named my dog after my favorite stout. I prefer crepes to pancakes, and use the batter to teach my kids algebra. I made a super-sized Jenga game for which hard-hats are recommended. I may have sung "Let it Go!" from Frozen at the top of my lungs one too many times...