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

L. Testi·F. D'Antona·F. Ghinassi·J. Licandro·A. Magazzu'·R. Maiolino·F. Mannucci·A. Marconi·N. Nagar·A. Natta·E. Oliva
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Abstract

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.

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L. Testi, F. D'Antona, F. Ghinassi, J. Licandro, A. Magazzu', R. Maiolino, F. Mannucci, A. Marconi, N. Nagar, A. Natta, E. Oliva. 2001-04-08. NICS-TNG low-resolution 0.85-2.45um spectra of L-Dwarfs: a near-infrared spectral classification scheme for faint dwarfs. https://doi.org/10.1086/320348

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