Table of Contents
ISRN Astronomy and Astrophysics
Volume 2011, Article ID 725697, 8 pages
Research Article

The Dark Matter Halo Density Profile, Spiral Arm Morphology, and Supermassive Black Hole Mass of M33

1Department of Physics and Astronomy, University of Arkansas at Little Rock, 2801 S. University Avenue, Little Rock, AR 72204-1099, USA
2Arkansas Center for Space and Planetary Sciences, 202 Old Museum Building, University of Arkansas, Fayetteville, AR 72701, USA

Received 28 January 2011; Accepted 3 March 2011

Academic Editor: N. Caon

Copyright © 2011 Marc S. Seigar. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We investigate the dark matter halo density profile of M33. We find that the HI rotation curve of M33 is best described by an NFW dark matter halo density profile model, with a halo concentration of 𝑐 v i r = 4 . 0 ± 1 . 0 and a virial mass of 𝑀 v i r = ( 2 . 2 ± 0 . 1 ) × 1 0 1 1 M . We go on to use the NFW concentration ( 𝑐 v i r ) of M33, along with the values derived for other galaxies (as found in the literature), to show that 𝑐 v i r correlates with both spiral arm pitch angle and supermassive black hole mass.