The first spectroscopically identified L dwarf in Praesepe

We have obtained a low-resolution optical spectrum for one of the faintest cluster member candidates in Praesepe with the Optical System for Imaging and low Resolution Integrated Spectroscopy mounted on the 10.4 m Gran Telescopio de Canarias. We confirm spectroscopically the first L dwarf member in...

Full description

Saved in:
Bibliographic Details
Published in:Monthly notices of the Royal Astronomical Society 2013-09, Vol.434 (1), p.142-147
Main Authors: Boudreault, S., Lodieu, N.
Format: Article
Language:English
Subjects:
Constellations
Double stars
Dwarf stars
Probability
Space telescopes
Spectrum analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We have obtained a low-resolution optical spectrum for one of the faintest cluster member candidates in Praesepe with the Optical System for Imaging and low Resolution Integrated Spectroscopy mounted on the 10.4 m Gran Telescopio de Canarias. We confirm spectroscopically the first L dwarf member in Praesepe, UGCS J084510.66+214817.1. We derived an optical spectral type of L0.3±0.4 and estimated its effective temperature to T eff = 2279 ± 371 K and a mass of 71.1 ± 23.0 M Jup, according to state-of-the-art models, placing it at the hydrogen-burning boundary. We measured the equivalent width of the gravity-sensitive sodium doublet at 8182/8194 Å, which adds credit to the membership of this new L dwarf to Praesepe. We also derived a probability of ∼20.5 per cent that our candidate would be a field L0 dwarf. We conclude that this object is likely to be a true member of Praesepe, with evidence of being a binary system.
ISSN:0035-8711
1365-2966
DOI:10.1093/mnras/stt1009