New ultracool subdwarfs identified in large-scale surveys using Virtual Observatory tools.

Subdwarfs are metal-poor low-mass stars located in the halo or thick disk of our Galaxy. They appear less luminous than their solar counterparts, show high proper motions, and strong metal-hydride absorption bands and metal lines in their optical spectra. We conducted a photometric and astrometric search for subdwarfs with Virtual Observatory tools. We obtained low-resolution optical spectra for 77 of 100 candidates and classified them using two methods: spectral indices and templates. We report 72 new ultracool subdwarfs, including 2 new L subdwarfs. We checked WISE photometry of known and new subdwarfs and present some preliminary results.