Abstract:
Precision Doppler spectroscopy serves as an important tool for Radial Velocity (RV) observations of stars. High
precision spectroscopy is bound by two major challenges, first being the instrument instability which is mainly
caused by temperature and pressure variations and second, the limitations imposed by traditional wavelength
calibration methods. In this work we report our progress on the development of a passively stabilized Fabry-Perot
(FP) calibrator. We have designed and built an air-spaced etalon with 30 GHz free spectral range for accurately
tracking the short-term drift of our high resolution (R = 60,000) Echelle spectrograph on Himalayan Chandra
Telescope (HCT), Hanle. Instrument is built using off-the-shelf components, with the required temperature and
pressure stability being achieved in initial test runs. For transporting light in and out of the vacuum system
without incurring losses at fiber interconnects, we have used a simple way to insert a FC/APC connectorized
fiber into the flange. We also present the results of transmission spectra of the FP taken with high resolution
Fourier Transform Spectrometer.
