サガワ ヒデオ   SAGAWA HIDEO
  佐川 英夫
   所属   京都産業大学  理学部 宇宙物理・気象学科
   職種   教授
言語種別 英語
発行・発表の年月 2010/07
形態種別 研究論文
査読 査読あり
標題 The Herschel-SPIRE submillimetre spectrum of Mars
執筆形態 その他
掲載誌名 Astronomy & Astrophysics
出版社・発行元 EDP SCIENCES S A
巻・号・頁 518,pp.L151
著者・共著者 Swinyard, B. M,al,incl,Sagawa
概要 We have obtained the first continuous disk averaged spectrum of Mars from 450 to 1550 Ghz using the Herschel-SPIRE Fourier-transform spectrometer. The spectrum was obtained at a constant resolution of 1.4 GHz across the whole band. The flux from the planet is such that the instrument was operated in "bright source" mode to prevent saturation of the detectors. This was the first successful use of this mode and in this work we describe the method used for observing Mars together with a detailed discussion of the data reduction techniques required to calibrate the spectrum. We discuss the calibration accuracy obtained and describe the first comparison with surface and atmospheric models. In addition to a direct photometric measurement of the planet the spectrum contains the characteristic transitions of (12)CO from J 5-4 to J 13-12 as well as numerous H(2)O transitions. Together these allow the comparison to global atmospheric models allowing the mean mixing ratios of water and (12)CO to be investigated. We find that it is possible to match the observed depth of the absorption features in the spectrum with a fixed water mixing ratio of 1 x 10(-4) and a (12)CO mixing ratio of 9 x 10(-4).
DOI 10.1051/0004-6361/201014717
ISSN 0004-6361