Productive Sabbatical
for Dr. Cominsky

Dr. Lynn Cominsky has been on sabbatical leave during this past school year. Her leave was partially funded by a grant from the National Science Foundation’s Career Advancement Award program. The program gives funds to under-represented scientists to help them change their career directions.

For the past twenty years, Dr. Cominsky has been doing research in high-energy astrophysics, mostly studying X-ray binary stars. About five years ago she started working with particle physicists at the Stanford Linear Accelerator Center (SLAC) who were interested in building a new type of high-energy gamma-ray telescope. This telescope, called GLAST (Gamma-ray Large Area Space Telescope) will study active galaxies, pulsars and supernovae in the energy range 10 MeV 300 GeV. However, it is also the first space observatory with the potential to do particle physics experiments. Exploring the capability of GLAST to study several important problems in particle physics was the subject of Dr. Cominsky’s NSF proposal. The work has required her to learn some particle physics, which is a significantly different area of research than her previous interests.

One problem, on which she is working with local high school student Daniel Mazeau, involves the ability of GLAST to detect high energy line emission from the self-annihilation of supersymmetric particles (WIMPs), whose existence is hypothesized by particle physicists in some Grand Unified Theories. The existence of WIMPs (Weakly Interacting Massive Particles) would also provide a possible solution to the dark matter problem in cosmology. Mazeau’s work on this subject with Dr. Cominsky enabled him to become a semi-finalist in the 1997 Westinghouse Science Talent Search.

Dr. Cominsky has also continued her activities as the press officer for the High Energy Astrophysics Division (HEAD) of the American Astronomical Society (AAS). In November 1997 she organized two successful press conferences for the AAS/HEAD meeting which was held in Estes Park, Colorado. Coverage of the two stories was excellent, with front page articles appearing in the Los Angeles Times, and many other dailies, as well as radio coverage and a spot on CNN. The first story reported the discovery of a diffuse halo of high-energy gamma-rays around our Galaxy, while the second provided evidence for “frame-dragging” in binaries containing neutron stars and black holes. Frame-dragging is an effect that is a prediction of Einstein’s theory of General Relativity, and refers to the phenomenon where a massive rotating body will drag space-time along with it, as it spins, much like a top stuck in gooey molasses.

Her press activities continued at the January 1998 meeting of the American Astronomical Society in Washington, DC, where she was named one of two new deputy press officers for the AAS. She conducted a press conference on new evidence which indicates that the universe is not only expanding, but that expansion is occurring at an increasing rate. She also organized a press conference on new X-ray and infrared observations of a rapidly spinning black hole in our Galaxy, which shows the first connection between the accretion disk around the compact object and the formation of jets emanating from its vicinity. It appears that the relativistic jets are somehow turned on by the sudden infall of the swirling disk of material that usually surrounds the black hole. The actual mechanism for forming the jets (which must start outside the black hole’s event horizon) remains unclear. The week in Washington was topped off by an appearance on National Public Radio’s Science Friday interview show with Ira Flatow, in which she and a scientist from the Cosmic Background Explorer mission discussed the astronomical highlights of the meeting.

In addition to Dr. Cominsky’s work on the GLAST project, she has also been involved in preparing for the launch of the Unconventional Stellar Aspect X-ray astronomy experiment, which is on board the Argos spacecraft. With luck, Argos should finally be launched by the end of 1998. Dr. Cominsky has been leading the effort to ensure that all the calibration data needed to interpret the data are in place and integrated into the software used for scientific analysis. Her collaborators in this project are from the US Naval Research Laboratory in Washington, DC, and from SLAC.