|
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 |
|
| 発行・発表の年月 | 2020/12 |
| 形態種別 | 研究論文 |
| 査読 | 査読あり |
| 標題 | Evaluation of a method to retrieve temperature and wind velocity profiles of the Venusian nightside mesosphere from mid-infrared CO<inf>2</inf> absorption line observed by heterodyne spectroscopy |
| 執筆形態 | その他 |
| 掲載誌名 | Earth, Planets and Space |
| 巻・号・頁 | 72(1) |
| 著者・共著者 | Kosuke Takami,Hiromu Nakagawa,Hideo Sagawa,Pia Krause,Isao Murata,Yasumasa Kasaba,Takeshi Kuroda,Shohei Aoki,Toru Kouyama,Theodor Kostiuk,Timothy A. Livengood,Gabriella Gilli |
| 概要 | © 2020, The Author(s). We evaluated a method for retrieving vertical temperature and Doppler wind velocity profiles of the Venusian nightside mesosphere from the CO2 absorption line resolved by mid-infrared heterodyne spectroscopy. The achievable sensitive altitude and retrieval accuracy were derived with multiple model spectra generated from various temperature and wind velocity profiles with several noise levels. The temperature profiles were retrieved at altitudes of 70–100 km with a vertical resolution of 5 km and a retrieval accuracy of ± 15 K. The wind velocity was also retrieved at an altitude of approximately 85 km with a vertical resolution of 10 km and a retrieval accuracy of ± 25–50 m/s. In addition, we studied an event and applied our method to spectra obtained by the HIPWAC instrument attached to the NASA/IRTF 3-m telescope on May 19–22, 2012. Retrieved wind velocities in a latitude of 33° S at 3:00 LT were interpreted as subsolar-to-antisolar (SS-AS) flows at altitudes of 84 ± 6 km and 94 ± 7 km, and they were stronger than expected. This result suggested that the transition between the retrograde superrotational zonal (RSZ) wind and SS-AS flow may occur at altitudes below 90 km which previously was predicted to be the transition region. This work provides a basis for our analysis of further observations obtained by a mid-infrared heterodyne spectrometer MILAHI attached to the Tohoku University 60-cm telescope at Haleakalā, Hawaii.[Figure not available: see fulltext.]. |
| DOI | 10.1186/s40623-020-01188-0 |
| ISSN | 1343-8832/1880-5981 |