Abstract:
High precision spectroscopy is bounded by two major challenges, first being
instrument instability, mainly caused by temperature and pressure variations,
and second is due to the limitations of traditional calibration methods. Spec-
trographs require suitable calibration sources for precise Radial velocity (RV)
measurements. Emission lamps do not provide homogenous line distributions
and intensities, giving limited wavelength coverage and spectrum contami-
nation from di erent sources. A wavelength calibrator based on Fabry-Perot
interferometer can provide stable transmission lines covering full wavelength
range and can achieve 1-10 m/s RV precision. A vacuum enclosure has been
designed and constructed for the Fabry-Perot to be mounted in to minimize
pressure fluctuation effects. Enclosure temperature is being controlled using
a Proportional-Integral (PI) controller to provide thermal stability.
