Research articles

search articles

My Pages

Stat

Members: 3645
Articles: 2'501'711
Articles rated: 2609

20 April 2024

» arxiv » 1910.3076

Article overview

Dwarfs or giants? Stellar metallicities and distances from $ugrizG$ multi-band photometry
Guillaume F. Thomas ; Nicholaas Annau ; Alan McConnachie ; Sebastien Fabbro ; Hossen Teimoorinia ; Patrick Côté ; Jean-Charles Cuillandre ; Stephen Gwyn ; Rodrigo A. Ibata ; Else Starkenburg ; Raymond Carlberg ; Benoit Famaey ; Nicholas Fantin ; Laura Ferrarese ; Vincent Hénault-Brunnet ; Jaclyn Jenssen ; Ariane Lancon ; Geraint F. Lewis ; Nicolas F. Martin ; Julio F. Navarro ; Céline Reylé ; Rubén Sánchez-Janssen ;
Date:	7 Oct 2019
Abstract:	We present a new fully data-driven algorithm that uses photometric data from the Canada-France-Imaging-Survey (CFIS; $u$), Pan-STARRS 1 (PS1; $griz$), and Gaia ($G$) to discriminate between dwarf and giant stars and to estimate their distances and metallicities. The algorithm is trained and tested using the SDSS/SEGUE spectroscopic dataset and Gaia photometric/astrometric dataset. At [Fe/H]$<-1.2$, the algorithm succeeds in identifying more than 70\% of the giants in the training/test set, with a dwarf contamination fraction below 30\% (with respect to the SDSS/SEGUE dataset). The photometric metallicity estimates have uncertainties better than 0.2 dex when compared with the spectroscopic measurements. The distances estimated by the algorithm are valid out to a distance of at least $sim 80$ kpc without requiring any prior on the stellar distribution, and have fully independent uncertainities that take into account both random and systematic errors. These advances allow us to estimate these stellar parameters for approximately 12 million stars in the photometric dataset. This will enable studies involving the chemical mapping of the distant outer disc and the stellar halo, including their kinematics using the Gaia proper motions. This type of algorithm can be applied in the Southern hemisphere to the first release of LSST data, thus providing an almost complete view of the external components of our Galaxy out to at least $sim 80$ kpc. Critical to the success of these efforts will be ensuring well-defined spectroscopic training sets that sample a broad range of stellar parameters with minimal biases. A catalogue containing the training/test set and all relevant parameters within the public footprint of CFIS is available online.
Source:	arXiv, 1910.3076
Services:	Forum \| Review \| PDF \| Favorites

No review found.

Did you like this article?

This article or document is ...
important:
of broad interest:
readable:
new:
correct:
Global appreciation:

Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.

browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)

ScienXe.org
» my Online CV
» Free

News, job offers and information for researchers and scientists:

home

contact

sitemap