Tuesday

The James Webb Space Telescope (JWST) will provide a great opportunity to explore high redshift galaxies, and understand the role of galaxies in the reionization of the Universe. I will present our observational plans for the Guaranteed Time Observations of the NIRSpec Instrument Science Team, including those co-ordinated with the NIRCam Team as part of the JWST Advanced Deep Extragalactic Survey (JADES).
We will chart galaxy evolution at z>2, and potentially out to z>10, using the rest-frame optical and near-IR though observations from 1-5microns. NIRSpec spectroscopy will measure secure spectroscopic redshifts of the photometrically-selected population, and emission lines can constrain the dust attenuation, star formation rates, metallicity, chemical abundances, ionization and excitation mechanism in high redshift galaxies. Potentially we can search for signatures of Population III stars such as He II. Determining the UV luminosity function to faint magnitudes, coupled with more accurate determinations of the escape fraction (from observations of the Balmer lines and UV continuum), will address the ionizing photon budget from galaxies. The census of the fraction of high redshift star-forming galaxies with Lyman alpha in emission will constrain the neutral fraction of the IGM at z>6, and the size of the ionized bubbles, and the study of rest-UV absorption lines and nebular emission will shed light on the outflows and the role of the circum-galactic medium. Working at between 1 and 5 microns, NIRSpec on JWST has the capability to explore the star formation rates, metallicities and IGM surroundings of galaxies within the epoch of reionization.