Semi-blind separation of galaxy spectra from a mixture obtained by slitless spectroscopy
Ahmed Selloum, Shahram Hosseini, T. Contini, Yannick Deville · 2015
We investigate the problem of separating galaxy spectra from their mixtures resulting from the slitless spectroscopy used in the future Euclid space mission. This can be formulated as a source separation problem where the structure of the mixture is specific and depends on a low number of parameters. We first develop a mathematical model to describe the observations generated by the near-infrared spectrograph of Euclid, then propose non-blind, semi-blind and regularized semi-blind methods to separate the spectra. The first simulation results are encouraging: even for a signal to noise ratio of 5 dB, our regularized semi-blind method succeeds in separating the considered two spectra and provides a satisfactory estimate of the emission line positions and amplitudes.