Spectrograph with High dispersion Echelle grating for Terrestrial exoplanetary Atmosphere (SHETA) for the LAPYUTA mission

JAXA recently selected LAPYUTA (Life-environmentology, Astronomy, and PlanetarY Ultraviolet Telescope Assembly) as a candidate for JAXA's Small Scale Program No. 6 to be launched by Epsilon in ~2032. We will accomplish the following four objectives: #1 Solar System, #2 Exoplanets, #3 Galaxies, #4 the origin of heavy elements. To achieve these scientific objectives, LAPYUTA aims to carry out spectroscopy with a large effective area (>300 cm2) and a high spatial resolution (0.1 arc-sec) and imaging in far ultraviolet spectral range (110-190 nm). A high dispersion spectrograph with a spectral resolution of > 40000 is required, especially for observing exospheres of terrestrial (Earth-like) exoplanets. We are considering the design of the Spectrograph with High dispersion Echelle grating for the Terrestrial (exo-)planetary Atmosphere (SHETA) as an instrument. In this presentation, we introduce the scientific objective and the conceptual design of the SHETA instrument.