Improving identification of weak spectral lines in the presence of a strong continuum

Abstract

Observing faint spectral signals from light sources in the presence of an overwhelming background is a common goal in many aspects of physics and astronomy. By using an optimized selected part of a Fourier interferogram, we demonstrate that observability of such faint signals can be much improved. We present astronomical observations, in an on-sky experiment, made on several spectral types of star using a breadboard common path scanless interferometer on the Wise Observatory 1m telescope. We obtain an improvement of signal-to-background of up to 35 for a given exposure time.