Exploring high-z galaxies with the E-ELT

TL;DR

This study uses simulations to evaluate the capabilities of the E-ELT and JWST in measuring the properties of high-redshift galaxies, demonstrating that E-ELT can achieve high accuracy in size and brightness measurements at z=2 and z=3.

Contribution

The paper provides a detailed simulation-based assessment of the E-ELT's ability to analyze high-z galaxies, highlighting its potential for precise measurements of galaxy structure and photometry.

Findings

E-ELT can measure galaxy size and magnitude with 5% accuracy at z=2 and z=3.

Effective radius of compact galaxies can be recovered with 5% accuracy if larger than 20 mas.

E-ELT's capabilities are compared with JWST's NIRCam simulations.

Abstract

In this paper we present simulated observations of galaxies at z=2 and z=3 to probe the capabilities of next-generation telescopes (E-ELT and JWST) to measure the structural and photometrical properties of high redshift galaxies. We carry out an extensive set of simulations of high redshift galaxies adopting the specifications of the E-ELT first light instrument MICADO. The main parameters (sizes, Sersic index, magnitudes) of the galaxies are measured using GALFIT and the accuracy of the determinations is assessed by comparing the input values to the measurements from many runs with different statistical noise. We also address the effects on the measurements accuracy of possible spatial variation of the PSF in the field. We find that from 3h exposure E-ELT near-IR images of galaxies at z=2 and z=3 it will be possible to measure the size, the total magnitude and the galaxy morphology with an accuracy of 5% for objects as faint as H=25 and half light size of 0.2 arcsec. The effective radius of compact, early type galaxies will also be recovered with 5% accuracy, provided that their half light size exceeds 20 mas. These results are compared with those expected from simulated observations obtained with NIRCam on board of the JWST.