The dark matter haloes that surround galaxies are expected to be non-spherical. One way of investigating departures from sphericity is to study the shapes of the luminous discs of spiral galaxies. As part of the work for my master's degree, I performed -- by visual inspection -- a morphological classification of nearly 4000 galaxies using images from the Sloan Digital Sky Survey. Having obtained more than 1600 spirals suitable for our purposes, I measured the shapes of their discs. By statistical deprojection, we found that their discs display a mild intrinsic non-circularity.
For more details, see my MSc dissertation or the defense presentation. This project was supported by FAPESP.
