  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.
