1RXS 1609B: a Brown Dwarf Orbiting its Parent Star at 350 AU and has an Inclined Dusty Circum Brown Dwarf Disk

New Extinction and Mass Estimates of the Low-mass Companion 1RXS 1609 B with the Magellan AO System: Evidence of an Inclined Dust Disk

Authors:

Wu et al

Abstract:

We used the Magellan adaptive optics system to image the 11 Myr substellar companion 1RXS 1609 B at the bluest wavelengths to date (z' and Ys). Comparison with synthetic spectra yields a higher temperature than previous studies of Teff=2000±100K and significant dust extinction of AV=4.5+0.5−0.7 mag. Mass estimates based on the DUSTY tracks gives 0.012-0.015 Msun, making the companion likely a low-mass brown dwarf surrounded by a dusty disk. Our study suggests that 1RXS 1609 B is one of the 25% of Upper Scorpius low-mass members harboring disks, and it may have formed like a star and not a planet out at 320 AU.