PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 69(1) 2017年2月 [査読有り]
We present a general surface brightness correction method for compact extended sources imaged in the slow-scan pointed observation mode of the Far-Infrared Surveyor (FIS) aboard the AKARI infrared astronomical satellite. Our method recovers correc...
The detection of the CO2 absorption band at 4.2 mu(m) in brown dwarf spectra by AKARI has made it possible to discuss CO2 molecular abundance in brown dwarf atmospheres. In our previous studies, we found an excess in the 4.2 mu m CO2 absorption ba...
S. Sorahana   I. Yamamura   H. Murakami   
Astrophysical Journal 767(1) 2013年4月 [査読有り]
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 0.64-1.13 RJ with an average radius of 0.83 RJ . We find a trend in the ...
We investigate variations in the strengths of three molecular bands, CH4 at 3.3 mu m, CO at 4.6 mu m, and CO2 at 4.2 mu m, in 16 brown dwarf spectra obtained by AKARI. Spectral features are examined along the sequence of source classes from L1 to ...
We present the discovery of a source with broadband infrared photometric characteristics similar to Sakurai's object. WISE J180956.27-330500.2 (hereafter J1810-3305) shows very red WISE colors, but a very blue 2MASS [K] versus WISE [W1 (3.4 mu m)]...
T Onaka   T de Jong   Yamamura, I   
ASTRONOMY & ASTROPHYSICS 388(2) 573-586 2002年6月
The M-type Mira variable star, Z Cyg, was observed with the Short-Wavelength Spectrometer (SWS) on board the Infrared Space Observatory (ISO) 7 times at roughly 60 day intervals over one and a half period. The infrared spectrum (2.38-45.2 mum) of ...
M Matsuura   Yamamura, I   J Cami   T Onaka   H Murakami   
ASTRONOMY & ASTROPHYSICS 383(3) 972-986 2002年3月
The time variation in the water-vapour bands in oxygen-rich Mira variables has been investigated using multi-epoch ISO/SWS spectra of four Mira variables in the 2.5-4.0 mum region. All four stars show H2O bands in absorption around minimum in the ...
M Matsuura   Yamamura, I   J Cami   T Onaka   H Murakami   
ASTRONOMY & ASTROPHYSICS 383(3) 972-986 2002年3月
The time variation in the water-vapour bands in oxygen-rich Mira variables has been investigated using multi-epoch ISO/SWS spectra of four Mira variables in the 2.5-4.0 mum region. All four stars show H2O bands in absorption around minimum in the ...
We report the discovery in the ISO/SWS spectrum of the post-AGE star HR 4049 of emission bands due to O-17 and O-18 isotopes locked up in CO2 molecules. It is the first time these isotopomers are detected outside the solar system. Isotopic ratios ...