Share Email Print

Proceedings Paper

Adaptive optics high-resolution IR spectroscopy with silicon grisms and immersion gratings
Author(s): Jian Ge; Daniel Ludlow McDavitt; Abhijit Chakraborty; John Luther Bernecker; Shane Miller
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The breakthrough of silicon immersion grating technology at Penn State has the ability to revolutionize high-resolution infrared spectroscopy when it is coupled with adaptive optics at large ground-based telescopes. Fabrication of high quality silicon grism and immersion gratings up to 2 inches in dimension, less than 1% integrated scattered light, and diffraction-limited performance becomes a routine process thanks to newly developed techniques. Silicon immersion gratings with etched dimensions of ~ 4 inches are being developed at Penn State. These immersion gratings will be able to provide a diffraction-limited spectral resolution of R = 300,000 at 2.2 micron, or 130,000 at 4.6 micron. Prototype silicon grisms have been successfully used in initial scientific observations at the Lick 3m telescope with adaptive optics. Complete K band spectra of a total of 6 T Tauri and Ae/Be stars and their close companions at a spectral resolution of R ~ 3000 were obtained. This resolving power was achieved by using a silicon echelle grism with a 5 mm pupil diameter in an IR camera. These results represent the first scientific observations conducted by the high-resolution silicon grisms, and demonstrate the extremely high dispersing power of silicon-based gratings. New discoveries from this high spatial and spectral resolution IR spectroscopy will be reported. The future of silicon-based grating applications in ground-based AO IR instruments is promising. Silicon immersion gratings will make very high-resolution spectroscopy (R > 100,000) feasible with compact instruments for implementation on large telescopes. Silicon grisms will offer an efficient way to implement low-cost medium to high resolution IR spectroscopy (R ~ 1000-50000) through the conversion of existing cameras into spectrometers by locating a grism in the instrument's pupil location.

Paper Details

Date Published: 7 February 2003
PDF: 8 pages
Proc. SPIE 4839, Adaptive Optical System Technologies II, (7 February 2003); doi: 10.1117/12.459156
Show Author Affiliations
Jian Ge, The Pennsylvania State Univ. (United States)
Daniel Ludlow McDavitt, The Pennsylvania State Univ. (United States)
Abhijit Chakraborty, The Pennsylvania State Univ. (United States)
John Luther Bernecker, The Pennsylvania State Univ. (United States)
Shane Miller, The Pennsylvania State Univ. (United States)

Published in SPIE Proceedings Vol. 4839:
Adaptive Optical System Technologies II
Peter L. Wizinowich; Domenico Bonaccini, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?