Zakhozhay, O. V., Osorio, M. R. Z., Bejar, V. J. S., Boehler, Y. 2017. Spectral energy distribution simulations of a possible ring structure around the young, red brown dwarf G 196-3 B. Monthly Notices of the Royal Astronomical Society 464, 1, 1108-1118, DOI: 10.1093/mnras/stw2308
The origin of the very red optical and infrared colours of intermediate-age (similar to 10-500 Myr) Ltype dwarfs remains unknown. It has been suggested that low-gravity atmospheres containing large amounts of dust may account for the observed reddish nature. We explored an alternative scenario by simulating debris disc around G 196-3 B, which is an L3 young brown dwarf with amass of similar to 15M(Jup) and an age in the interval 20-300 Myr. The best-fit solution to G 196-3 B’s photometric spectral energy distribution from optical wavelengths through 24 mu m corresponds to the combination of an unreddened L3 atmosphere (T-eff approximate to 1870 K) and a warm (approximate to 1280 K), narrow(approximate to 0.07-0.11 R-circle dot) debris disc located at very close distances (approximate to 0.12-0.20 R-circle dot) from the central brown dwarf. This putative, optically thick, dusty belt, whose presence is compatible with the relatively young system age, would have a mass >= 7 x 10(-10) M-circle plus comprised of submicron/micron characteristic dusty particles with temperatures close to the sublimation threshold of silicates. Considering the derived global properties of the belt and the disc-tobrown dwarf mass ratio, the dusty ring around G 196-3 B may resemble the rings of Neptune and Jupiter, except for its high temperature and thick vertical height (approximate to 6 x 10(3) km). Our inferred debris disc model is able to reproduce G 196-3 B’s spectral energy distribution to a satisfactory level of achievement.
