Skip to main content
SearchLoginLogin or Signup

A FUV to NIR Accounting of the Accretion Luminosity of the Young Brown Dwarf 2M1207A

Presentation #305.26 in the session Stars, Cool Dwarfs, Brown Dwarfs — iPoster Session.

Published onJun 29, 2022
A FUV to NIR Accounting of the Accretion Luminosity of the Young Brown Dwarf 2M1207A

It is unclear whether young brown dwarfs have similar magnetic field geometries or undergo the same magnetospheric accretion processes as young stars. The material surrounding an accreting brown dwarf may have lower infall velocities and a larger filling factor, akin to the planetary accretion paradigm. Different formation scenarios would also yield different initial conditions, affecting the amount of gas and dust that can accrete onto brown dwarfs. Over the past 20 years, the young brown dwarf 2MASSW J1207-3932 (2M1207), a member of the TW Hya association, has been observed at FUV, NUV, optical, and infrared wavelengths and confirmed to be accreting material from its surrounding disk. In fact, 2M1207 is the only accreting brown dwarf that has been observed across such an expansive wavelength range. In this work, I combine multiple archival datasets to measure and provide a multi-wavelength, comprehensive accretion luminosity and line emission analysis for 2M1207. Meanwhile, I investigate the consistency of stellar and planetary accretion relationships in the substellar regime. This study will provide an unprecedented accounting of accretion luminosity across multiple accretion tracers for a substellar object, which will allow us to more accurately estimate mass accretion rate and ultimately inform the formation and accretion mechanisms of brown dwarfs. We find that the secondary accretion line tracers used for estimating accretion rate yield a dramatic range of accretion rates for brown dwarfs(spanning 2-4 dex for Hα, Hβ, and Paβ), which depend on which empirical scaling relationships are adopted.

No comments here