Target Selection for the SDSS-III MARVELS Survey
Abstract
We present the target selection process for the Multi-object APO Radial Velocity Exoplanets Large-area Survey (MARVELS), which is part of the Sloan Digital Sky Survey (SDSS) III. MARVELS is a medium-resolution (R ∼ 11,000) multi-fiber spectrograph capable of obtaining radial velocities for 60 objects at a time in order to find brown dwarfs and giant planets. The survey was configured to target dwarf stars with effective temperatures approximately between 4500 and 6250 K. For the first 2 years MARVELS relied on low-resolution spectroscopic pre-observations to estimate the effective temperature and log (g) for candidate stars and then selected suitable dwarf stars from this pool. Ultimately, the pre-observation spectra proved ineffective at filtering out giant stars; many giants were incorrectly classified as dwarfs, resulting in a giant contamination rate of ∼30% for the first phase of the MARVELS survey. Thereafter, the survey instead applied a reduced proper motion cut to eliminate giants and used the Infrared Flux Method to estimate effective temperatures, using only extant photmetric and proper-motion catalog information. The target selection method introduced here may be useful for other surveys that need to rely on extant catalog data for selection of specific stellar populations.
- Publication:
-
The Astronomical Journal
- Pub Date:
- June 2015
- DOI:
- 10.1088/0004-6256/149/6/186
- arXiv:
- arXiv:1505.04708
- Bibcode:
- 2015AJ....149..186P
- Keywords:
-
- catalogs;
- planets and satellites: detection;
- stars: general;
- surveys;
- techniques: radial velocities;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Accepted by AJ