MOSFIRE Spectroscopy of Galaxies in Cosmic Noon

TL;DR

This paper presents the ZFIRE spectroscopic survey of galaxies at redshifts 1.5 to 2.5 using MOSFIRE, providing valuable data for understanding galaxy properties during the peak epoch of star formation.

Contribution

It introduces the ZFIRE survey, detailing its planning, data reduction, and data release, and demonstrates the importance of spectroscopy for studying galaxy properties at Cosmic Noon.

Findings

High mass-completeness of ZFIRE data at z~2.

Spectroscopic redshifts improve galaxy property measurements.

Data supports studies of star formation, metallicity, and IMF.

Abstract

The recent development of sensitive, multiplexed near infra-red instruments has presented astronomers the unique opportunity to survey mass/magnitude complete samples of galaxies at \emph{Cosmic Noon}, a time period where $\sim80\%$ of the observed baryonic mass is generated and galaxies are actively star-forming and evolving rapidly. This thesis takes advantage of the recently commissioned MOSFIRE spectrograph on Keck, to conduct a survey (ZFIRE) of galaxies at $1.5<z<2.5$ to measure accurate spectroscopic redshifts and basic galaxy properties derived from multiple emission lines. The majority of the thesis work involved survey planning, observing, data reduction, and catalogue preparation of the ZFIRE survey and is described in detail in this thesis. Using the ZFIRE spectroscopic redshifts, I show why spectroscopy is instrumental to determine fundamental galaxy properties via SED fitting techniques and to probe gravitationally bound structures in the early universe. The thesis further presents basic properties of the ZFIRE data products publicly released for the benefit of the astronomy community. The high mass-completeness of the ZFIRE spectroscopic data at $z\sim2$ makes it ideal to study fundamental galaxy properties such as, star formation rates, metallicities, inter-stellar medium properties, galaxy kinematics, and the stellar initial mass functions in unbiased star-forming galaxies. This thesis focuses on one such aspect, the IMF.