| |
 |
| Paper: |
A New Multichannel Fourier Transform Spectrometer |
| Volume: |
185, Precise Stellar Radial Velocities, IAU Colloquium 170 |
| Page: |
36 |
| Authors: |
Nordgren, T. E.; Hajian, A. R. |
| Abstract: |
Stellar spectra have been obtained using a Fourier Transform Spectrometer (FTS) which incorporates components of the new Navy Prototype Optical Interferometer (NPOI). It is well known that an FTS possesses superior wavelength stability over traditional spectrometers, even those using absorption cells for wavelength calibration. Unfortunately, the FTS traditionally suffers from exceptionally poor sensitivity, which until now has limited its uses to sources with high fluxes and/or those which only emit over narrow bandwidths (e.g. the Sun, certain nebulae and laboratory samples). We present stellar observations using a new FTS design which overcomes this sensitivity limitation by using a conventional spectrometer in conjunction with the FTS system. Our test-bed observations, using an effective 12cm diameter aperture, produce spectra with velocity resolutions and signal to noise ratios consistent with the theoretical prediction. We have extrapolated our results to a system where the 32 channel NPOI spectrometer has been replaced with one of 3000 channels and the 12cm siderostat is replaced by a large aperture telescope. With this type of an instrument we expect to be able to detect and measure such exciting astrophysical phenomena as gravitational redshifts from single, main sequence stars and extrasolar planets of terrestrial mass. |
|
|
|
|
|
