A long-standing and profound problem in astronomy is the difficulty in obtaining deep near-infrared observations from the ground due to the extreme brightness and variability of the night sky at these wavelengths. The atmospheric emission at 1.0 - 1.7 um arises almost entirely from a forest of extremely bright, very narrow OH emission lines that vary on timescales of minutes. Using an approach known as a fiber Bragg grating (FBG), these emission lines can now be selectively removed, while retaining high throughput between the lines.
Dr. S. Veilleux of the University of Maryland College Park and his international team have carefully refined the application of this technique by incorporating an Integral Field Unit (IFU) FBG input, and have thoroughly demonstrated the efficacy of the approach through in situ tests with existing telescopes and instrumentation. The requested NSF funds are highly leveraged through FBG development at the University of Sydney and spectrograph construction being provided by the NASA Goddard Space Flight Center as well as the University of Maryland. Science applications will initially focus on low-resolution spectroscopy of very faint, transient gamma-ray burst (GRB) sources, which are now known to originate in supernovae located in very distant galaxies, as well as on studies of the galaxies that host these cataclysms. Teaming with Discovery Communications provides an unusual outreach component to the project that will involve students at a variety of levels as well as the general public.
Funding this component of the near-infrared OH emission-line suppression spectrograph is being provided by NSF's Division of Astronomical Sciences through its Advanced Technologies and Instrumentation program.
