A Rapid-Response Gamma-Ray Burst Afterglow Observing Program at Etelman Observatory in the US Virgin Islands

摘要

The College of Charleston (CofC) is one of three institutions that belong to a consortium led by the Division of Science and Mathematics at the University of the Virgin Islands (UVI) to maintain and operate a research grade telescope at Etelman Observatory on the island of St. Thomas (18deg, 21 N, 65deg W at an elevation ~ 1325 ft with 1 seeing). The location provides 80% sky coverage of the southern celestial hemisphere and, on average, ~ 6 hours of clear sky per night, except during the peak of hurricane season. This makes the observatory an ideal facility for observing Gamma-Ray Bursts (GRBs). The observatory will serve a variety of needs to the consortium members that include research, teaching, and public outreach. The primary research function of this facility will be to perform rapid, automated followup observations of Gamma-Ray Bursts (GRBs) observed with NASA's Swift spacecraft, to be launched in June 2004, via the GCN. The newly renovated observatory houses a new robotic 0.5 m Cassegrain telescope with a back-illuminated Marconi 2024 × 2024 CCD42-40 imaging array and 12-position UBVRI filter wheel. Assuming 1.5 seeing and a S/N=5, we can obtain a limiting (unfiltered) magnitude of ~ 19 with a 10 s integration time. The slew rate is 10deg per second.With the exceptional sky coverage at Etelman Observatory, we anticipate a detection rate of about 10–15% of the Swift detection rate, and we anticipate making a significant contribution to the global network of small telescopes dedicated to GRB observations.