Using a Monte Carlo Simulation to Resolve Through Confusion the Radio Source Background of Weak Radio Sources Out to Z = 2.9

Grierson, Melanie, Astronomy, University of Virginia
Sarazin, Craig, Department of Astronomy, University of Virginia

This thesis details how to create a simulated universe on a 1000'' x 1000'' sky with 1'' x 1'' pixels. The simulated sky was created to provide a realistic distribution of radio sources given a specific source count and includes instrumental observing effects associated with the Karl G. Janksy Very Large Array (VLA). 1.4 GHz counts from Condon et al. (2012), which underwent a spline interpolation, were used to create ≈ 37k radio sources ranging from 10E3 to 10E-8 Jy. These realistic sources allowed for the determination of the number of galaxies per flux density bin with a spacing of 0.01 in log flux density in order to calculate the fraction of galaxies on the sky with each corresponding flux density. Each of the simulated galaxies was smeared by an 8'' FWHM point spread function (PSF) and was assigned a random galaxy location, in which the flux densities of overlapping sources are summed. In order to more closely approximate and mimic the instrumental effects obtained on a VLA observation, both the Gaussian primary attenuation pattern with a 14' FWHM and a convolution of the confusion amplitude distribution with the VLA's Gaussian instrumental noise distribution are included within the simulation. This simulation program will be used to analyze a confusion-limited VLA observation intended to study the star-formation history of the universe by counting radio sources as faint as S ~ 0.2 μJy.

BS (Bachelor of Science)
Confusion, Star Formation History of the Universe, Monte Carlo Simulation, Star Formation Rate Density
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