Document Type


Date of Degree

Spring 2014

Degree Name

MS (Master of Science)

Degree In


First Advisor

Cornelia C. Lang


Despite the Radio Arc non-thermal filaments (NTFs) being discovered 30 years ago, their origin remain poorly understood. The Radio Arc NTFs have an unusually flat spectrum in the centimeter to millimeter spectrum with a predicted, though poorly constrained, turn-over between 30-200 GHz. With the recently upgraded wide-band capabilities of the VLA, we conducted a multi-frequency polarimetric study of the Radio Arc region. With observations at a set of low radio frequencies (continuous coverage over 2-6 GHz & 10-12 GHz), we imaged both the total and polarized intensity distributions at high angular resolution (<1"). Presented here are the preliminary results from four observations spanning May 2013 to February 2014 using the DnC, CnB, B & BnA array configurations. This study has produced the deepest continuum intensity images of the Radio Arc region to date, with a sensitivity an order of magnitude greater than previous surveys, and resulted in the detection of new structure and compact emission sources. These observations will serve as a pilot polarization study for larger, more complete polarimetric surveys of the Galactic center region.


ix, 67 pages


Includes bibliographical references (pages 65-67).


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Copyright 2014 James Toomey