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SCORCH (Simulations and Constructions of the Reionization of Cosmic Hydrogen) is a new project to study the Epoch of Reionization (EoR). In this first paper, we probe the connection between observed high-redshift galaxies and simulated dark matter halos to better understand the abundance and evolution of the primary source of ionizing radiation. High-resolution N-body simulations are run to quantify the abundance of dark matter halos as a function of mass $M$, accretion rate $dot{M}$, and redshift $z$. A new fit for the halo mass function $dn/dM$ is $approx 20%$ more accurate at the high-mass end where bright galaxies are expected to reside. A novel approach is used to fit the halo accretion rate function $dn/ddot{M}$ in terms of the halo mass function. Abundance matching against the observed galaxy luminosity function is used to estimate the luminosity-mass relation and the luminosity-accretion-rate relation. The inferred star formation efficiency is not monotonic with $M$ nor $dot{M}$, but reaches a maximum value at a characteristic mass $sim 2 times 10^{11} M_odot$ and a characteristic accretion rate $sim 6 times 10^2 M_odot/{rm yr}$ at $z approx 6$. We find a universal EoR luminosity-accretion-rate relation and construct a fiducial model for the galaxy luminosity function. The Schechter parameters evolve such that $phi_star$ decreases, $M_star$ is more positive (fainter), and $alpha$ is more negative (steeper) at higher redshifts. We forecast for the upcoming James Webb Space Telescope and show that with apparent magnitude limit $m_{rm AB} approx 31 (32)$, it can observe $gtrsim 11 (24)$ unlensed galaxies per square degree per unit redshift at least down to $M_star$ at $z lesssim 13 (14)$.
According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic density f
We present measurements of carbon, oxygen, silicon, and iron in quasar absorption systems existing when the universe was roughly one billion years old. We measure column densities in nine low-ionization systems at 4.7 < z < 6.3 using Keck, Magellan,
We present a robust measurement and analysis of the rest-frame ultraviolet (UV) luminosity function at z=4-8. We use deep Hubble Space Telescope imaging over the CANDELS/GOODS fields, the Hubble Ultra Deep Field and the Year 1 Hubble Frontier Field d
The intergalactic medium (IGM) is the dominant reservoir of baryons at all cosmic epochs. We investigate the evolution of the IGM from z=2-0 in 48 Mpc/h, 110-million particle cosmological hydrodynamic simulations using three prescriptions for galacti
Empirical models of galaxy formation require assumptions about the correlations between galaxy and halo properties. These may be calibrated against observations or inferred from physical models such as hydrodynamical simulations. In this Letter, we u