70 citations · 302 across the 10 of their papers we have counts for
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Carbon-to-Oxygen Ratios in M dwarfs and Solar-type stars
Tadashi Nakajima, Satoko Sorahana
Initial C/O ratios of circumstellar disks have been obtained in solar-type stars by differential photospheric abundance analysis with respect to the Sun. We present C/O ratios of M…
AKARI Observations of Brown Dwarfs. IV. Effect of Elemental Abundances to Near-Infrared Spectra between 1.0 and 5.0 μm
Satoko Sorahana, Issei Yamamura
The detection of the CO_2 absorption band at 4.2 μm in brown dwarf spectra by AKARI has made it possible to discuss CO_2 molecular abundance in brown dwarf atmospheres. In our prev…
An Approach for Retrieving Temperatures and Abundances in Brown Dwarf Atmospheres
Michael R. Line, Jonathan J. Fortney, Mark S. Marley +1
Brown dwarf spectra contain a wealth of information about their molecular abundances, temperature structure, and gravity. We present a new data driven retrieval approach, previousl…
A Signature of Chromospheric Activity in Brown Dwarfs Revealed by 2.5-5.0 Micron AKARI Spectra
Satoko Sorahana, Takeru K. Suzuki, Issei Yamamura
We propose that the 2.7 micron H_2O, 3.3 micron CH_4 and 4.6 micron CO absorption bands can be good tracers of chromospheric activity in brown dwarfs. In our previous study, we fou…
On the Radii of Brown Dwarfs Measured with AKARI Near-Infrared Spectroscopy
Satoko Sorahana, Issei Yamamura, Hiroshi Murakami
We derive the radii of 16 brown dwarfs observed by AKARI using their parallaxes and the ratios of observed to model fluxes. We find that the brown dwarf radius ranges between 0.64-…
Akari Observations of Brown Dwarfs. II CO2 as Probe of Carbon and Oxygen Abundances in Brown Dwarfs
Takashi Tsuji, Issei Yamamura, Satoko Sorahana
Recent observations with the infrared astronomical satellite AKARI have shown that the CO2 bands at 4.2 micron in three brown dwarfs are much stronger than expected from the unifie…