Grupo de Sistemas Estelares

Lorenzo-Gutiérrez, A.; Alfaro, E. J.; Maíz Apellániz, J.; Barbá, R. H.; Marín-Franch, A.; Ederoclite, A.; Cristóbal-Hornillos, D.; Varela, J.; Vázquez Ramió, H.; Cenarro, J.; Lennon, D. J.; García-Lario, P.
Monthly Notices of the Royal Astronomical Society, Volume 486, Issue 1, p.966-980 (2019).
06/2019

ABSTRACT

This paper describes the characterization of the GALANTE photometric system, a seven intermediate- and narrow-band filter system with a wavelength coverage from 3000 Å to 9000 Å. We describe the photometric system presenting the full sensitivity curve as a product of the filter sensitivity, CCD, telescope mirror, and atmospheric transmission curves, as well as some first- and second-order moments of this sensitivity function. The GALANTE photometric system is composed of four filters from the J-PLUS photometric system, a twelve broad-to-narrow filter system, and three exclusive filters, specifically designed to measure the physical parameters of stars such as effective temperature T_eff, log (g), metallicity, colour excess E(4405 - 5495), and extinction type R₅₄₉₅. Two libraries, the Next Generation Spectral Library (NGSL) and the one presented in Maíz Apellániz & Weiler (2018), have been used to determine the transformation equations between the Sloan Digital Sky Survey (SDSS) ugriz photometry and the GALANTE photometric system. We will use this transformation to calibrate the zero-points of GALANTE images. To this end, a preliminary photometric calibration of GALANTE has been made based on two different griz libraries (SDSS DR12 and ATLAS All-Sky Stellar Reference Catalog, hereinafter RefCat2). A comparison between both zero-points is performed leading us to the choice of RefCat2 as the base catalogue for this calibration, and applied to a field in the Cyg OB2 association.