12 papers
The Challenge of Observing Patchy Reionization with CMB Optical-Depth Fluctuations
Nick Takoudes, Hanjue Zhu, Nickolay Y. Gnedin
Spatial fluctuations in the Thomson optical depth encode information about the inhomogeneous nature of cosmic reionization. We compute the optical-depth angular power spectrum, $C_…
Photon (Non)Conservation in the Reduced Speed of Light Approximation and How to (Almost) Fix It
Nickolay Y. Gnedin
The "Reduced Speed of Light" (RSL) approximation is commonly used to speed up radiative transfer calculations in cosmological simulations. However, it has been shown previously tha…
Second Order Closures for the Radiative Transfer Equation: Some Are Unstable
Nickolay Y. Gnedin, Harley Katz
The largest existing simulations of cosmic reionization model radiative transfer with moment methods that require a closure relation. The two most commonly used closure relations a…
Effects of Primordial Black Holes on IGM History
Emily Koivu, Nickolay Y. Gnedin, Christopher M. Hirata
Currently the asteroid mass window (mass grams) remains unconstrained for Primordial Black Holes (PBHs) to make up all of the dark matter content of the uni…
Damping Wing-Like Features in the Spectra of High Redshift Quasars: a Challenge for Fully-Coupled Simulations
Nickolay Y. Gnedin, Hanjue Zhu
Recently, several observational detections of damping-wing-like features at the edges of ``dark gaps" in the spectra of distant quasars (the ``Malloy-Lidz effect") have been report…
Do We Know How to Model Reionization?
Nickolay Y. Gnedin
I compare the power spectra of the radiation fields from two recent sets of fully coupled simulations that model cosmic reionization: "Cosmic Reionization On Computers" (CROC) and…