Poster abstract
Search and spectroscopic characterization of ultracool subdwarfs.
Abstract
Ultracool subdwarfs are important tracers of the chemical enrichment of the Galaxy and likely belong to the first generation of stars.
We have cross-matched several large database, including UKIDSS, SDSS, and 2MASS, to look for ultracool subdwarf candidates i.e. metal-poor dwarfs with spectral types later than M5. We have obtained optical spectra of a large sample of candidates with VLT/FORS2 and GTC/OSIRIS to confirm (or otherwise) their low-metallicity status. In this poster, we present the photometric selection and preliminary results of the spectroscopic follow-up.
We have cross-matched several large database, including UKIDSS, SDSS, and 2MASS, to look for ultracool subdwarf candidates i.e. metal-poor dwarfs with spectral types later than M5. We have obtained optical spectra of a large sample of candidates with VLT/FORS2 and GTC/OSIRIS to confirm (or otherwise) their low-metallicity status. In this poster, we present the photometric selection and preliminary results of the spectroscopic follow-up.