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arXiv · astro-ph/0301155

Time resolved spectroscopy of the variable brown dwarf Kelu-1

F. J. Clarke·C. G. Tinney·S. T. Hodgkin
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Abstract

We report the results of observations designed to investigate the spectroscopic signatures of dust clouds on the L2 brown dwarf Kelu-1. Time resolved medium resolution spectra show no significant evidence of variability in the dust sensitive TiO, CrH and FeH bandheads on the timescale of 1--24 hours. We do however report periodic variability in the psuedo-equivelent width of H-alpha consistent with the 1.8 hour rotation period previously reported for this object Clarke, Tinney & Tolley (2002). Near-contemporaneous I-band photometry shows evidence for non-periodic variability at the level of 2%.

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F. J. Clarke, C. G. Tinney, S. T. Hodgkin. 2003-01-09. Time resolved spectroscopy of the variable brown dwarf Kelu-1. https://doi.org/10.1046/j.1365-8711.2003.06405.x

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