STEPS TOWARDS ASTRONOMICAL COMPONENT SEPARATION WITH C-BASS

UoM administered thesis: Master of Science by Research

  • Authors:
  • Karenne Mata-Figueras

Abstract

The C-Band All Sky Survey (C-BASS) is a ground-based survey that maps the whole sky at 5 GHz via two telescopes, one in the Northern hemisphere and one in the Southern hemisphere. C-BASS was designed to provide a whole sky survey at low frequencies that maps intensity and polarisation without artefacts, without ground pick-up and without being corrupted by Faraday rotation. One of the last steps left to achieve the final maps with the data from the Northern observations is to remove the ground pick-up. The main part of this thesis is focused in the method used to remove the ground pick-up for C-BASS and the results gathered so far with respect to the performance of the method. The results indicate that the ground removal is now successful. The maps generated with the data measured with the Northern telescope are one step closer to be in its final state, especially in intensity. The results prove the ground pick-up to be almost stable with time. The results are especially good at elevation 37◦ but are more unstable at the other elevations confirming the need of improving the method. The rest of the thesis describes a first attempt for the component separation (for the intensity) using an early C-BASS map generated from 15 months of observations of the Northern C-BASS telescope. The emission maps resulted from the method are close to the expected but at the moment it is fixing the spectral index from the synchrotron emission. The method uses a parabola to model spinning dust emission. It is not clear from the results that this simplification works and it has to be improved.

Details

Original languageEnglish
Awarding Institution
Supervisors/Advisors
Award date31 Dec 2016