SONOMA STATE UNIVERSITY

Observatory Report 1995-96

reprinted from the Bulletin of the American Astronomical Society 29, 1, 580-81 (1997).

This report, the Department's twentieth, covers the period September 1995 through August 1996. More up-to-date information may be found at the Department of Physics and Astronomy pages. Reports from other years are also available.

I. PERSONNEL

The faculty consisted of professors Lynn R. Cominsky, John R. Dunning, Samuel L. Greene, Duncan E. Poland (Chair), Saeid Rahimi, Gordon G. Spear (Observatory Director), and Joseph S. Tenn. Spear spent a second year on leave to SSU's Information Technology department.

II. INSTRUCTION

A total of 490 students took Descriptive Astronomy, Introductory Observational Astronomy, Extraterrestrial Intelligence and Interstellar Travel, Frontiers in Astronomy, Cosmology, and Astrophysics: Stars.

The Department awarded 2 B.A. degrees and 6 B.S. degrees. (All degrees are in physics.) There were 39 physics majors in Spring 1996.

III. EQUIPMENT

Optical telescopes are mounted in a sliding-roof observatory on campus. Auxiliary instrumentation for the 0.36-m Schmidt-Cassegrain telescope includes a CCD camera, an f/10 guide scope, a 0.2-m f/3 Baker-Schmidt camera, wide field cameras, a slitless prism spectrograph, a dispersion grating spectrograph with a Hg-Ne comparison source, and a 0.5 Å H alpha

filter.

The Epoch Instruments 0.25-m f/5 Newtonian telescope is computer-controlled. The system points reliably to within 1-2 arcminutes on the sky. When used with the AstroLink CCD camera, the resulting images have a 20 arcminute field of view and a 2 arcsecond/pixel image scale. Reliable photometry is feasible for objects as faint as 16th magnitude.

IV. RESEARCH

Cominsky continued working part-time in the Particle Astrophysics Group at the Stanford Linear Accelerator Center on projects involving X-rays and high-energy gamma-rays. She is helping to develop a ground data system for the Unconventional Stellar Aspect Experiment, which will be launched on the ARGOS satellite in 1997. She is also working on science simulation for high-energy gamma-ray detectors using silicon strip technology as part of a NASA approved mission concept study. Student Rachel Hansen has been assisting with this work.

Cominsky has continued to study the X-ray emission from the radio pulsar-Be binary PSR 1259-63, that she originally discovered in 1993. Guest observer observations to obtain additional data on this object near apastron were made with the ASCA, OSSE and RXTE experiments. In addition, she has been collaborating with SSU graduate Mallory Roberts (now at Stanford University) on analyzing observations of the black hole candidate 4U1755-33 (RXTE), the Be-star transient binary 4U0115+63 (BATSE) which underwent a new outburst in 1995 and the high-mass neutron star binary 4U1907+09 (ASCA). Using new data from RXTE, work continues with Paul Hertz and Kent Wood from the Naval Research Laboratory on understanding the eclipses and orbital timing of the transient system EXO 0748-676.

Cominsky was appointed Press Officer for the April 1996 meeting of the High Energy Astrophysics Division of the American Astronomical Society, which was held in San Diego, CA. She organized two press conferences, featuring new results from RXTE and from active galaxies, which received considerable attention from the press. This was the first time that the HEAD/AAS had organized its results for the media. Due to the success of the effort, Cominsky was appointed Press Officer for the 1997 HEAD/AAS meeting to be held in Colorado.

V. MISCELLANEOUS

The optical observatory was used 12 times for public viewing nights, classes, and tours. There were 447 visitors.

The Department presented its "What Physicists Do" public lecture series, under Tenn's and Cominsky's direction, for the 50th and 51st semesters. Visiting speakers on astronomical topics were Ben Owen (Caltech), Joel Primack (U of California, Santa Cruz), Kevin Hurley (U of California at Berkeley), Virginia Trimble (U of California, Irvine), Halton C. Arp (Max Planck Institute for Astrophysics), and Richard E. Young (NASA Ames Research Center).

Tenn was appointed to a second three-year term as chair of the Astronomical Society of the Pacific history committee. He arranged a history session devoted primarily to the history of astronomy in California for the ASP annual meeting, held in Santa Clara in June.

VI. PUBLICATIONS

Bender, P., Bloom, E., Cominsky, L., Ford, H., Harmon, A., Michelson, P., Novikov, I., Postnov, K., Scargle, J., Swank, J., Wheeler, J. C., and Wood, K., 1995 "Black Hole Astrophysics", in the Proceedings of the 1994 Snowmass Summer Study on High Energy Physics: Particle and Nuclear Astrophysics and Cosmology in the Next Millennium, eds. E. W. Kolb and R. D. Peccei, World Scientific: Singapore, p. 377.

Cominsky, L., Roberts, M., and Finger, M., 1995, "The 1994 Large Outburst from 4U0115+63 Observed by BATSE," B. A. A. S., 27, 1434.

Rubin, B. C., Finger, M. H., Harmon, B.A., Paciesas, W. S., Fishman, G. J., Wilson, R. B., Wilson, C. A., Brock, M. N., Briggs, M. S., Pendleton, G., N., Cominsky, L. R., and Roberts, M. S., 1996, "Observations of 4U1700-37 with BATSE," Astrophysical Journal, 459, 259.

Tenn, Joseph S. 1995, "Bruce Medalist Profile: Alfred Fowler," Mercury 24, 5, 36.

Joseph S. Tenn
submitted October 1996