10ケルビンで氷から吸収された水の統計的オーソ対パラ比
Tetsuya Hama1, Akira Kouchi2, Naoki Watanabe2
1Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan. hama@lowtem.hokudai.ac.jp.
まとめ
ガスの水
科学分野:
- 天体化学
- 星間媒体の物理
- 惑星科学
背景:
- 水のオーソ対パラ比 (OPR) は,空間の氷形成温度を推測するために使用されます.
- この方法では,水のOPRは,その氷形成温度を塵粒に反映すると仮定します.
研究 の 目的:
- 水のオーソ対パラ比 (OPR) と氷の形成温度との関係を調査する.
- 恒星間氷の形成温度を決定するためにOPRの使用を再評価する.
主な方法:
- 10 ケルビンで O2 を水素化することによって,氷の形成です.
- 脱吸収された水分子のOPRの測定
主要な成果:
- 10ケルビンの氷から吸収した水は,低形成温度と矛盾する高OPR3を示した.
- この発見は,水のOPRが氷の形成温度と直接相関しているという仮定に異議を唱えます.
結論:
- 水のOPRと氷の形成温度との推定関係は無効である.
- 低OPRの再解釈は,彗星形成を含む恒星間水の化学史と初期の太陽系プロセスを理解するために不可欠です.
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