Laurence E. Peterson
Research ProfessorPh.D. Minnesota, 1960
The High Energy Astronomy group, which I lead, studies the nature of objects in the Universe which emit X-rays and gamma-rays. Such objects include solar flares, neutron stars, white dwarfs, black holes, supernovae remnants and active galactic nuclei. Detectable diffuse emissions occur from the galaxy as well as from cosmological distances. Radiation at these high energies is produced by plasmas at extreme temperatures, by relativistic particles in high magnetic fields and by Compton scattering on ambient radiation fields. Particles producing X-rays may also be energized in strong gravitational fields.
My group has pioneered the development of low background collimated detectors operating in the 10 keV to 10 MeV range. These detector systems are flown on high altitude balloons and on various NASA space missions, including the Compton Gamma-Ray Observatory launched in 1991, and the X-Ray Timing Explorer, scheduled for launch in 1995. Under development are instruments using cooled Ge detectors to accomplish high resolution gamma-ray spectroscopy. These will observe nucleosynthetic gamma-rays and positron annihilation processes in supernova, compact objects, the galactic center and disk, and in active galactic nuclei.
Our program includes, besides instrumental developments, observations from balloons and satellites, data analysis, and in conjunction with associates, theoretical studies and modelling of the emitting sources.
Selected publication:
Instrumental Technique in X-Ray Astronomy. Annual Reviews of Astronomy and Astrophysics 13, 423 (1975).
2-165 keV Observations of Active Galaxies and the Diffuse Background. With R.E. Rothschild, et al. Astrophys. J. 269, 423 (1982).
A Scanning Modulation Collimator Observation of the High Energy X-Ray Source in the Crab Nebula. With R.M. Pelling et al. Astrophys. J. 319, 416 (1987).
Observation of SN 1987A with the Gamma-Ray Spectrometer HEXAGONE. With C.G.L. Chapuis, et al. Astrophys. J. 403, 332 (1993).
Compton-Backscattered Annihilation Radiation from the Galactic Center Region. With D.M. Smith et al. Astrophys. J, 414, 165 (1993).
©University of California, San Diego - Department of Physics 1998
Creation / Modification Date: February 1, 1999
