A Supernova Search Telescope (Abstract)

Volume 23 number 2 (1995)

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Mark T. Adams

Fort David, TX

William R. Wren

Fort Davis, TX

Abstract

(Abstract only) Despite progress in the management and operation of professional, low redshift CCD-based supernova (SN) search programs, many nearby supernovae continue to be discovered byvisual searches (e.g., SN 1995ad). Since September 1990, Wren has conducted a visual supernova search using his personal 18-inch, f/4.5 Dobsonian telescope, and for approximately3 nights a month near full moon, the McDonald Observatory 36-inch telescope. These effortshave led to Wren's visual discovery of SNe 1992H and 1994Y. For experienced visual observers, the supernova discovery rate is limited primarily by the search rate. With the above equipment, Wren's average search rate is approximately 1.4 minutes per galaxy. Increasing the supernova discovery rate requires optimization of the observing environment.To this end, an innovative supernova search telescope has been constructed at theMcDonald Observatory. This telescope will at least halve the observing time per galaxy, fromapproximately 1.4 minutes per galaxy to less than 0.7 minutes per galaxy, yielding a higher discovery rate per unit observing interval. This new Supernova Search Telescope (SNST) was dedicated in May 1995 as the George B. Wren II SNST. Its construction incorporates the innovative "Fundyscope: optical design (Sky & Telescope 1992, 84, 212). Built with a DudleyObservatory Fullham Award for Innovation, a grant from the Pipeline Inspection Company(Houston, TX), and a National Science Foundation grant, the George B. Wren II SNST incorporates the key Fundyscope design features; a rigid mount, low diffraction optics, and a fixed viewing position. In addition to increased search rate, this SNST will reduce observer fatigue, a critical factor in visual SN search, allowing longer observing sessions.As constructed, the SNST uses an 18-inch, f/4.5 primary mirror and a 24-inch diametercontrol mirror. Under the dark McDonald Obvseratory West Texas skies, the SNST will becapable of SN search to visual magnitude +16. Routine operations are expected to begin in January 1996. A sample of 1300+ galaxies will be surveyed. Future plans for this SNST include the acquisition and use of a large-format CCD camera.Numerous individuals have contributed to this project's realization. Their contribuitons aregratefully acknowledge: J. Craig Wheeler (Professor of Astronomy, UT-Austin McDonaldObservatory), Michael Marcario (High Lonesome Optics; Fort Davis, TX), Steve Watkins (Homestead Construction Co.; Houston, TX), John Hudek (Galaxy Optics; Buena Vista, CO), George Grubb (McDonald Observatory Physical Plant), Earl Green (McDonald Observatory Observing Support), and Wayne Rosing (The Robotic Telescope Company; Los Gatos, CA).