Uncertainties in Spiral Galaxy Projection Parameters
Abstract
We investigate the impact of nonaxisymmetric structure on estimates of galaxy inclinations and position angles. A new minimization technique is used to obtain estimates of inclination and position angle from a global fit to either photometric or kinematic data. We discuss possible systematic uncertainties that are much larger than statistical uncertainties. Our investigation reveals that systematic uncertainties associated with fitting photometric data dominate the formal statistical uncertainties. For our sample of inclined galaxies, we estimate that nonaxisymmetric features introduce inclination and position angle uncertainties of ~5°, on average. The magnitudes of these uncertainties weaken the arguments for intrinsically elliptical galaxy disks.
- Publication:
-
The Astronomical Journal
- Pub Date:
- March 2003
- DOI:
- 10.1086/346142
- arXiv:
- arXiv:astro-ph/0211225
- Bibcode:
- 2003AJ....125.1164B
- Keywords:
-
- Galaxies: Fundamental Parameters;
- Galaxies: Kinematics and Dynamics;
- Galaxies: Photometry;
- Astrophysics
- E-Print:
- submitted to AJ, Rutgers Preprint #365