Radio Emission from Starburst Galaxies

  • Antonia Hawker

Student thesis: Master of Science by Research


The nearby nuclear starburst in M82 provides an ideal opportunity to study a prototypical star-forming galaxy in detail. Previous work has detected roughly 55 compact sources within the starburst region. Studying starbursts, such as that in M82, allows us to understand the environments in which stars form and evolve. The aim of this work is to produce a new catalogue of sources within M82 and to classify them as far as possible. In order to do this new images have been analysed which are deeper than previously presented. Three C-band images have been used to create a final catalogue, followed by an L-band image in order to analyse their spectral indices. A total of 90 sources have been identified above 0.02mJy, compared with a previous total of 55. The characteristics of all sources have been measured including size, flux density and, where possible, spectral indices. The majority of the sources are supernova remnants (SNRs), followed by Hii regions and several sources which remain as unclassified due to the morphological and spectral information being inconclusive. 53 of the sources have been identified to be SNRs, 27 Hii regions and 9 sources remain as unclassified. For sources classified as SNRs, their luminosity has been calculated and compared to that of Cassiopeia A. 28 of the sources were more luminous than Cassiopeia A. These have therefore been assumed to be younger and have been used to calculate the supernova rate in M82. This was found to be 0.082yr−1. The supernova rate was then used to calculate the star formation rate which was calculated as 2-2.25 M⊙ for those more massive than 5 M⊙ taking lower and upper mass limits of 0.1 and 100M⊙.
Date of Award1 Aug 2018
Original languageEnglish
Awarding Institution
  • The University of Manchester
SupervisorThomas Muxlow (Supervisor) & Rob Beswick (Supervisor)

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