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A Flaring L5 Dwarf: The Nature of HαEmission in Very Low Mass (Sub)Stellar Objects

James Liebert·J. Davy Kirkpatrick·K. L. Cruz·I. Neill Reid·Adam Burgasser·C. G. Tinney·John E. Gizis
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Abstract

Time series spectrophotometry of the L5 dwarf 2MASS 01443536-0716142 showed strong Hαemission which declined by nearly 75% in four consecutive exposures. The line was not detected in emission on a spectrum obtained eleven months later. This behavior constrasts with that of 2MASSI J1315309-264951, an L5 dwarf which has shown even stronger Hαemission on four separate occasions. The observational database suggests that L dwarfs can be found in such strong flares only occasionally, with a duty cycle of order 1%. In contrast, the few, continuously-strong Hαemitters, including PC 0025+0447 and 2MASSI J1237392+652615, must either be (1) objects no older than 10-100 Myrs with continuously-active accretion and/or chromospheres, but which apparently formed in isolation from known young stellar clusters and associations, or (2) objects empowered by a different and unknown mechanism for the Hαenergy.

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James Liebert, J. Davy Kirkpatrick, K. L. Cruz, I. Neill Reid, Adam Burgasser, C. G. Tinney, John E. Gizis. 2002-10-16. A Flaring L5 Dwarf: The Nature of HαEmission in Very Low Mass (Sub)Stellar Objects. https://doi.org/10.1086/345514

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