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A Deep Look at the T-Type Brown Dwarf Binary $ε$ Indi Bab with Chandra and ATCA

M. Audard·A. Brown·K. R. Briggs·M. Guedel·A. Telleschi·J. E. Gizis
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Abstract

We present deep observations of the nearby T-type brown dwarf binary $ε$ Indi Bab in radio with the Australia Telescope Compact Array and in X-rays with the Chandra X-ray Observatory. Despite long integration times, the binary (composed of T1 and T6 dwarfs) was not detected in either wavelength regime. We reached $3σ$ upper limits of $1.23 \times 10^{12}$ and $1.74 \times 10^{12}$ erg/s/Hz for the radio luminosity at 4.8 GHz and 8.64 GHz, respectively; in the X-rays, the upper limit in the $0.1-10$ keV band was $3.16 \times 10^{23}$ erg/s. We discuss the above results in the framework of magnetic activity in ultracool, low-mass dwarfs.

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M. Audard, A. Brown, K. R. Briggs, M. Guedel, A. Telleschi, J. E. Gizis. 2005-04-19. A Deep Look at the T-Type Brown Dwarf Binary $ε$ Indi Bab with Chandra and ATCA. https://doi.org/10.1086/430881

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