MRI: Development of the Next Generation Palomar Spectrograph

California Institute Of Technology, Pasadena CA

Investigators

Abstract

The Next Generation Palomar Spectrograph (NGPS) will be an instrument for the Palomar Observatory. Its efficient design will record up to 70 percent of the light, compared to the 25 percent efficiency of typical spectrographs. This advance will lead to new discoveries in many different areas of astronomy such as asteroids, stars, black holes, and cosmic explosions. This project will also serve U.S. veterans through the Warrior-Scholar Project, which aids veterans in attaining four year college degrees. NGPS will be one of the most efficient single-object astronomical spectrographs. Located at the Cassegrain focus of the 200 inch Hale telescope, it will provide all-optical wavelength coverage (320-1040 nm). When used in a typical configuration (0.5 arcsec slice width), it will provide a resolving power of R = 4500. NGPS has been designed to maximize both optical and operational efficiency. Technical innovations, such as a slit-slicer and volume phase holographic diffraction gratings, yield an instrument optical efficiency of 70 percent. The adjustable slit-slicer allows for minimization of slit losses while increasing the spectral resolution. Operational innovations include an acquisition-and-guide camera with a 4.4 arcmin field of view. This area is large enough for instant, automated recognition of the field for an arbitrary pointing anywhere on the sky. This means that the target can be centered on the slit without human intervention, enabling a minimal acquisition time of just 7.5 seconds after slewing to the field. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.