Gaia capabilities to determine the length and angle of the Galactic bar
Abstract
We use a test particle simulation evolved under a 3D potential that includes a Galactic bar to analyse the Gaia capabilities to determine the length and the angle of the Galactic bar. Using the pre-commissioning Gaia science performance models, we generate two realistic mock catalogues of Red Clump K giants. The first includes all stars up to Gaia magnitude, G, 20. The second requires good radial velocities from the Gaia RVS, so we allow a specific maximum error in radial velocity. Once the data from the commissioning phase have been analysed, we will be able to update the performance models and to generate and analyse new catalogues using more realistic input. For the catalogues available at the moment, we plot, for the first time, the stellar surface density in the space of Gaia observables (parallax, galactic longitude). In this space we study the Gaia capabilities to recover the bar characteristics imposed in the analytical potential. If we combine the Gaia data with photometric IR distances, we can recover the bar length and the angle with respect to the Sun - Galactic Centre line.
- Publication:
-
Highlights of Spanish Astrophysics VIII
- Pub Date:
- May 2015
- Bibcode:
- 2015hsa8.conf..564R