The next generation of space surveys in cosmology and galaxy evolution will focus on the questions that Euclid, the Roman Space Telescope and the Legacy Survey of Space and Time (LSST) will not resolve.
In fact, to understand galaxy and large-scale structure evolution, we require very large spectroscopic surveys at high redshifts. To map the cosmic web of dark matter using galaxies through most of cosmic history requires a redshift precision of ~0.0001 (i.e., slit spectroscopy), and a continuous IR wavelength coverage that is only possible from space. We would need a wide area galaxy redshift survey spanning the redshift range of 0.5<z<5, carried out using wide field multi-object slit spectroscopy from space.

This precision and redshift coverage is not attained by either Euclid or Roman grism spectroscopy, or by JWST (James Webb Space Telescope). For these reasons, the astronomical community is developing new concepts for space surveys. One of these is the concept of the ATLAS probe space mission. ATLAS (Astrophysics Telescope for Large Area Spectroscopy; https://atlas-probe.ipac.caltech.edu/) who will provide wide field multi-object slit spectroscopy with the required redshift precision of ~0.0001 in the redshift range 0.5<z<5.  

The PhD student will analyse spectroscopic observations with JWST and study the galaxy properties in clusters and groups at z>1.5. S/he will use this expertise to simulate spectroscopic observations that could be performed by a future space mission, based on the ATLAS Probe space mission proposal (https://atlas-probe.ipac.caltech.edu/). The proposal for this space mission will be submitted in the next years.