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Pennsylvania State University Astronomy and Astrophysics University Park, Pennsylvania 16802-6305 550 Pennsylvania State University Astronomy and Astrophysics University Park, Pennsylvania 16802-6305 This report covers the period from September 1, 1994 to presented the 1994 Marker Lecture Series in September. Sir August 31, 1995. Martin Rees from Cambridge University, England, presented the 1995 Marker Lecture Series in April. 1. PERSONNEL 1.1 Faculty 2. ACADEMIC PROGRAM The regular members of the faculty during the academic 2.1 Graduate and Undergraduate Majors year 1994-1995 were Professors Peter Me´sza´ros ~Department Twenty-nine graduate and sixty-three undergraduate as- Head!, France Co´rdova ~on leave as NASA Chief Scientist!, tronomy majors were enrolled during the academic year Eric Feigelson, Gordon Garmire ~Evan Pugh Professor!, Lawrence Ramsey, Douglas Sampson, Peter Usher, Daniel 1994-95. During that time, seven B.S. degrees and three Ph.D. degrees were awarded in Astronomy and Astrophysics. Weedman ~on leave as NASA Director of Astrophysics Di- Doctoral recipients were Windsor Morgan, Ralph Kraft, and vision! and Aleksander Wolszczan; Visiting Professor George Pavlov; Associate Professors Donald Schneider and Zhiyu Guo. Richard Wade; Assistant Professors Matthew Bershady, Jane Charlton, Robin Ciardullo, Pablo Laguna and Louis Winkler; and Senior Research Associate/Associate Professors David 2.2 Educational Initiative Burrows and John Nousek. The Department continues as a Site for NSF’s Research Research Associates in the program were Stuart Ander- Experiences for Undergraduate program Chester, PI and son, Margaret Chester, Robin Corbet, Audrey Garmire, Scott ~ Ramsey, Co-PI . The Site grant provides stipend and travel Horner, Ron Kollgaard, Chi-Wai Lee, David Lumb, James ! support for undergraduates to participate in research with Neff, Mark Skinner, Guy Stringfellow, Leisa Townsley, faculty members. Six undergraduates from other colleges and Robin Tuluie, Kim Weaver, and Alan Welty. Chester was universities were fully supported by the Site Grant, and three appointed Visiting Assistant Professor of Physics at Bucknell Penn State students received partial support. These nine stu- University for the 1994-5 academic year. Neff was appointed dents and additional Penn State students supported under to the Graduate Faculty. Joining the department as Research ~ individual faculty research grants! participated in a variety of Associates are Marcos Diaz ~formerly of the University of group activities. These included a colloquium series given by Sao Paulo, Brazil!, Philippos Papadopoulos ~formerly of Ar- faculty and visiting scientists, a workshop on Modern Detec- istotle University, Greece!, George Chartas ~formerly of Har- tors and Observational Techniques, an observing trip to the vard Smithsonian Center for Astrophysics!, Oleg Goldshmidt NRAO at Green Bank, and an introduction to optical observ- ~formerly of Tel Aviv University, Israel! and Zhiyu Guo ing at Penn State’s Black Moshannon Observatory. ~former graduate student at Penn State!. Adjunct Associate Professors include Richard Griffiths at the Space Telescope Science Institute and Hans Kraus at the Technischen Universitat, Munchen, Germany. 2.3 Astronomy Club The Astronomy Club completed 22 years of service to the 1.2 Visitors to the Department University and the local community. It continued to hold Open Houses about once a month during each semester, and Visitors to the department included Ute Kraus, postdoc- during the summer semester. These events attract hundreds toral fellow from the University of Tuebingen, Germany, of visitors to the roof of Davey Laboratory, where the won- Istva´n Horva´th from the Central Research Institute for Phys- ders of the night sky are shown. The Club also organized ics, Budapest, Hungary, and T. Padmanabhan from the Inter- various activities for members, such as star parties, observing University Center for Astronomy and Astrophysics, Pune, trips, and picnics. Their newsletter, The Nittany Observer, India, all working with Peter Me´sza´ros; Honglin Zhang from continued to carry informative and well-written articles and Ohio State University, working with Douglas Sampson; items of news. Members also participate in outreach pro- Randy McKee from Ithaca College, as a summer instructor; grams for school children, making use of the Department’s Katsuji Koyama from Kyoto University, working with Eric planetarium. Officers for 1994-1995 were: President, Maggie Feigelson; Ronald Polidan from NASA/Goddard, working Masetti; Vice President, Melissa Pantaleo; Secretary/ Trea- with Richard Wade; and Richard Kron from the University of surer, Chris Burns; Newsletter Editor, Doug Schwer; Fund Chicago, Fermi Lab, and Dario Trevese from the Universita Raiser/Sales, Eric Hilbert; and Student Advisors, Doug degli Studi, La Sapienza, Rome, both working with Matthew O’Neal and Darren Williams. Usher is the Club’s faculty Bershady. Vera Rubin from Carnegie Institute of Washington advisor. PENNSYLVANIA STATE UNIVERSITY 551 3. RESEARCH ACTIVITIES While some detailed design work has started on these instru- ments, none is fully funded. The high resolution spec- 3.1 Instrumentation for Observing trograph is furthest along with initial procurement of long 3.1.1 Optical lead items in progress at HET partner UT Austin. Detailed design work on the medium resolution spectrograph has be- The Hobby-Eberly Telescope: The year since we last re- gun at Penn State. ported has seen dramatic progress in the construction of the The design and construction of the telescope is managed Hobby-Eberly Telescope HET . The initial construction ~ ! by Thomas A. Sebring, HET project manager. For more in- phase of the building has been completed with only interior formation on the HET, its science programs or partnership finishing remaining. In addition, all major structural elements contact L. Ramsey, HET project scientist, at of the telescope have been completed, delivered and installed [email protected]. at the McDonald Observatory site near Fort Davis, Texas. Black Moshannon Observatory: Ramsey and Matus con- This includes the telescope structure, mirror support truss tinued work on the implementation of a near-IR array system and dome. July 1995 was a particularly busy month with the during this last year. Matus completed the electronic and telescope structure azimuth rotation system undergoing its control software for the system and carried out extensive initial tests, the dome being lifted into place and the first two testing and characterization during spring of 1995. Ramsey primary mirror segments, out of 91, being accepted from designed a simple fiber spectrograph which was imple- Kodak. From this time the external appearance of the facility mented by Matus and Ramsey. May 1995 saw first light of will hardly change. However substantial effort remains on this system with initial observations in the H band of Arctu- the installation of the myriad electrical and electronic control rus at a resolution of l/Dl;5000. This coming year we systems. hope to conduct initial observations testing the utility of this The final procurements for the tracker, mirror supports system and spectral region for precision radial velocity mea- and actuators are well underway. Delivery of the tracker late surements. in the first quarter of 1996 will allow us to accurately project first light, now expected in summer of 1996. This will take place with a simple diamond-turned surrogate spherical ab- 3.1.2 X-ray erration corrector system. This surrogate will allow the vital CCD Imaging Spectrometer on AXAF: The AXAF CCD test and de-bug of the novel HET tracking system without Imaging Spectrometer ~ACIS! passed its critical design re- simultaneously having to test the optically complex final view in June. The flight CCDs are being delivered to MIT spherical aberration corrector system. The final aberration and will be calibrated with X-rays during the winter of 1995/ corrector system along with the acquisition and guide sys- 96. A number of CCDs, both frontside and backside illumi- tems and instrument interface is currently in final design. At nated have been calibrated at BESSY in Berlin by our col- this time we see no threat to our plan to implement regular laborators at the MIT Center for Space Research. These science operations in mid-1997. CCDs form the standard by which the flight CCDs are com- With the construction of the telescope well along, the em- pared for absolute quantum efficiency. Backside illuminated phasis is turning to the science operations phase. The Hobby- CCDs have been made at Lincoln Laboratory based on a Eberly Telescope Consortium, which consists of University process developed for the High Energy Transient Explorer of Texas at Austin, Penn State, Stanford University and the (HETE). These CCDs have proven to be very stable under Universities of Goettingen and Munich in Germany, held a conditions expected in the AXAF orbit and on the ground science workshop at Penn State in June of 1995. Several prior to launch. The quantum efficiency is high below 0.5 representatives from other private and national projects were keV, but the energy resolution is substantially worse than the also present. The focus of this workshop was to coordinate frontside illuminated CCDs yet sufficient to separate orders and optimize those scientific programs that the HET partners from the objective grating spectrometers. Low energy events will likely execute within the first year of science operation show considerable splitting of charge between pixels. with particular attention paid to seeking efficiencies in
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