Penn State is a major center of activity on the theory of gamma-ray bursts, as well as on developing instrumentation for detecting GRB. The GRB theory group as of 2003 includes, besides Peter Meszaros, postdoctoral fellows Dr. Bing Zhang, Dr. Shiho Kobayashi, Dr. Soeb Razzaque, graduate student Lijun Gou, and undergraduate student Joe Flasher. Short-term visitors are Dr. Zigao Dai (summer 02). Other Penn State faculty partly involved in GRB theory are Profs. Steinn Sigurdsson and Pablo Laguna. Previous members of the GRB theory group include Dr. Maddalena Spada (now Florence, Italy), Mr. Chriss Weth (now U. Tuebingen, Germany); Dr. Alin Panaitescu (Princeton, now Texas); Dr. Hara Papathanassiou (U. Portsmouth, UK); Dr. Jorg Rachen (U. Utrecht, Netherlands); Prof. Istvan Horvath (Budapest); and Prof. Dan Reichart (U. North Carolina). Among current research topics being investigated are the formation of X-ray lines in massive GRB progenitor models, the radiation and pehenomenology of jets in GRB, the propagation and dynamics of relativistic jets inside progenitors, the GeV-TeV photon signatures of bursts and afterglows, and the ultra-high energy (TeV to ZeV) neutrino signals from GRB and AGN jets. On the photo, L to R: Soeb Razzaque, Shiho Kobayashi, Doug Cowen, Peter Meszaros, Bing Zhang, Lijun Gou.
On the experimental side, Penn State and NASA/Goddard are the main partners in Swift, a GRB Afterglow Midex mission proposal which is currently under construction, and scheduled for launch in 2003 December. Swift will be equipped with gamma-ray, x-ray and optical detectors for on-board follow-up, and capable of relaying to the ground arc-second quality burst coordinates within less than a minute from the burst trigger, allowing even mid-size ground-based telescopes to obtain prompt spectra and redshifts. This will permit much more detailed studies of the burst environment, the host galaxy, and the intergalactic medium between galaxies. The Penn State Swift activities (involving Drs. John Nousek, Dave Burrows, Marg Chester, Peter Roming and others) include developing and running the Ground Control Center for the satellite, to be housed at Penn State; building the X-ray CCD detectors and camera; and assembling and testing of the Optical Monitor to be flown on Swift. The Gamma-ray monitor is being built by the NASA Swift team, and other teams providing significant efforts include Mullard Space Science Lab, London; Brera Observatory, Milano; and Leicester University, UK. GRB optical afterglow work is also being carried out with the Hobby-Eberly 10-meter telescope, in operation in west Texas, led by Prof. Michael Eracleous from Penn State. Other Penn State GRB activities include participation in the development of the AMANDA and ICECUBE ultra-high energy neutrino detectors in Antartica, involving Profs. James Beatty, Douglas Cowen and Stephane Coutu from Penn State. Another GRB experimental effort is aimed at detection of gravitational wave signals from compact sources and GRB with LIGO , carried out through the Center for Gravitational Wave Physics, an NSF Physics Frontier Center at Penn State, involving Profs. E. Sam Finn, Pablo Laguna, Peter Meszaros, Steinn Sigurdsson.