DISCO: a Spatio-Spectral Recombiner for Pupil Remapping Interferometry

Pupil-remapping is a new high-dynamic range imagingtechnique that has recently demonstrated feasibility on sky. The current prototypes present however deceiving limiting magnitude, restricting the current use to the brightest stars in the sky. We propose to combine pupil-remapping with spatio-spectral encoding, a technique first applied to the VEGA/ CHARAinterferometer. The result is an instrument proposal, called "Dividing Interferometer for Stars Characterizations and Observations" (DISCO). The idea is to take profit of wavelength multiplexing when using a spectrographin order to pack as much as possible the available information, yet providing a potential boost of 1.5 magnitude if used in existing prototypes. We detail in this paper the potential of such a concept.