Abstract
We have observed the nearest known brown dwarfs, the binary system Ã"°Ã¢â‚¬Âº Indi Bab (d= 3.626 pc), for 8.6- and 4.8-GHz radio emission with the Australia Telescope Compact Array. If either brown dwarf emits radio flares, then they are respectively at least 5.5 and 1.2 times weaker than LP 944-20, the nearest brown dwarf with detected radio emission. We associate the ROSAT source 1WGA J2203.9 - 5647 with Ã"°Ã¢â‚¬Âº Indi Bab since the separation was about 30 arcsec at the time of the ROSAT observation. Assuming the association, then Ã"°Ã¢â‚¬Âº Indi Bab has an L0.4-2.4keV X-ray luminosity of 5.6 ÃÆ'Ã"šÃ†'ÂÃ"šÃ¢â‚¬" 1025 erg s-1 which makes it roughly a factor of 2 less luminous than LP 944-20. The radio non-detections imply that Ã"°Ã¢â‚¬Âº Indi Bab does not violate, or at least does not violate as strongly as LP 944-20, the GÃÆ'Ã"šÃ†'ÂÃ"šÃ‚¼del-Benz relationship of X-ray and radio emission.
Original language | English |
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Number of pages | 2 |
Journal | Monthly Notices of the Royal Astronomical Society |
Publication status | Published - 2004 |
Keywords
- brown dwarf stars
- double stars
- low mass stars
- solar radio emission
- É› Indi Bab