NICS-TNG low-resolution 0.85-2.45um spectra of L-Dwarfs: a near-infrared spectral classification scheme for faint dwarfs


L. Testi (1), F. D'Antona (2), F. Ghinassi (3), et al.

(1) Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, I-50125 Firenze, Italy

(2) Osservatorio Astronomico di Roma, Frascati, Italy

(3) Centro Galileo Galilei and Telescopio Nazionale Galileo


We present complete near-infrared (0.85-2.45 um), low-resolution (~100) spectra of a sample of 26 disk L-dwarfs with reliable optical spectral type classification. The observations have been obtained with NICS at the TNG using a prism-based optical element (the Amici device) that provides a complete spectrum of the source on the detector. Our observations show that low-resolution near-infrared spectroscopy can be used to determine the spectral classification of L-dwarfs in a fast but accurate way. We present a library of spectra that can be used as templates for spectral classification of faint dwarfs. We also discuss a set of near-infrared spectral indices well correlated with the optical spectral types that can be used to accurately classify L-dwarfs earlier than L6.

Mantained by: Leonardo Testi