EIFIS: a modular extreme integral field spectrograph for the 10.4m GTC

TL;DR

EIFIS is a modular, large field-of-view integral field spectrograph designed for the 10.4m GTC, covering optical wavelengths with medium resolution, enabling advanced astronomical observations.

Contribution

This paper introduces the conceptual design and feasibility study of EIFIS, a novel modular spectrograph with large field coverage and broad spectral range for extremely large telescopes.

Findings

Design covers 2.43 sq. arcmin with 6 modules.

Spectrograph achieves medium resolving power (~2400).

Feasibility of optical and mechanical design confirmed.

Abstract

EIFIS (Extreme Integral FIeld Spectrograph) is a modular integral field spectrograph, based on image slicers, and makes use of new, large format detectors. The concept is thought to cover the largest possible field of view while producing spectroscopy over the complete optical range (3 000 - 10 000 \r{A}) at a medium resolving power of about 2400. In the optimal concept, each module covers a field of view of 38" x 38" with 0.3" spaxels, which is fed into a double spectrograph with common collimator optics. The blue arm covers the spectral range between 3000 and 5600 \r{A} and the red arm between 5400 and 10100 \r{A}, allowing for an overlap range. The spectra are imaged onto 9.2k x 9.2k detectors using a double pseudoslit. The proposed design for the 10.4m Gran Telescopio Canarias uses a total of 6 such modules to cover a total of 2.43 square arcminutes. Here we will present the conceptual design of the instrument and a feasibility study of the optical and mechanical design of the spectrographs. We discuss the limitations and alternative designs and its potential to produce leading edge science in the era of extremely large telescopes and the James Webb Space Telescope.