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Title: On Improving Analytical Models of Cosmic Reionization for Matching Numerical Simulations

Abstract

The methods for studying the epoch of cosmic reionization vary from full radiative transfer simulations to purely analytical models. While numerical approaches are computationally expensive and are not suitable for generating many mock catalogs, analytical methods are based on assumptions and approximations. We explore the interconnection between both methods. First, we ask how the analytical framework of excursion set formalism can be used for statistical analysis of numerical simulations and visual representation of the morphology of ionization fronts. Second, we explore the methods of training the analytical model on a given numerical simulation. We present a new code which emerged from this study. Its main application is to match the analytical model with a numerical simulation. Then, it allows one to generate mock reionization catalogs with volumes exceeding the original simulation quickly and computationally inexpensively, meanwhile reproducing large scale statistical properties. These mock catalogs are particularly useful for CMB polarization and 21cm experiments, where large volumes are required to simulate the observed signal.

Authors:
ORCiD logo [1]
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  1. Univ. of Chicago, IL (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1258785
Report Number(s):
FERMILAB-THESIS-2016-10
1471230
DOE Contract Number:
AC02-07CH11359
Resource Type:
Thesis/Dissertation
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Kaurov, Alexander A. On Improving Analytical Models of Cosmic Reionization for Matching Numerical Simulations. United States: N. p., 2016. Web. doi:10.2172/1258785.
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Kaurov, Alexander A. On Improving Analytical Models of Cosmic Reionization for Matching Numerical Simulations. United States. doi:10.2172/1258785.
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Kaurov, Alexander A. Fri . "On Improving Analytical Models of Cosmic Reionization for Matching Numerical Simulations". United States. doi:10.2172/1258785. https://www.osti.gov/servlets/purl/1258785.
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@article{osti_1258785,
title = {On Improving Analytical Models of Cosmic Reionization for Matching Numerical Simulations},
author = {Kaurov, Alexander A.},
abstractNote = {The methods for studying the epoch of cosmic reionization vary from full radiative transfer simulations to purely analytical models. While numerical approaches are computationally expensive and are not suitable for generating many mock catalogs, analytical methods are based on assumptions and approximations. We explore the interconnection between both methods. First, we ask how the analytical framework of excursion set formalism can be used for statistical analysis of numerical simulations and visual representation of the morphology of ionization fronts. Second, we explore the methods of training the analytical model on a given numerical simulation. We present a new code which emerged from this study. Its main application is to match the analytical model with a numerical simulation. Then, it allows one to generate mock reionization catalogs with volumes exceeding the original simulation quickly and computationally inexpensively, meanwhile reproducing large scale statistical properties. These mock catalogs are particularly useful for CMB polarization and 21cm experiments, where large volumes are required to simulate the observed signal.},
doi = {10.2172/1258785},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 2016},
month = {Fri Jan 01 00:00:00 EST 2016}
}
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Thesis/Dissertation:
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DOI:  10.2172/1258785
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