近赤外線吸収による水ダイマーの大気検出
K Pfeilsticker1, A Lotter, C Peters
1Institut für Umweltphysik, INF 229, University of Heidelberg, D-69120 Heidelberg, Germany.
まとめ
研究者らは,長経路スペクトロスコーピーを用いて水ダイマー (WDs) を検出した. この発見は,大気光化学と気候研究におけるWDの理解を前進させます.
科学分野:
- 大気化学 大気化学
- スペクトル顕微鏡検査です.
- 分子物理学 分子物理学
背景:
- 水ダイマー (Water dimer,WD) は,水分子の弱い結合のペアである.
- WDは,光化学と気候に影響を与える可能性があります.
- 水モノマー (WM) とのスペクトルの重なり合いは,WDの検出を妨げています.
研究 の 目的:
- 水の吸収を測定するために,ダイマー.
- WDs.のOHストレッチモードオーバートーン移行を検出するには.
主な方法:
- 大気圏の長経路微分光学吸収スペクトロスコーピー (18.34 km).
- 近赤外線OHのストレッチモードのオーバートーン移行の測定.
主要な成果:
- 749.5 nmで観測されたWD吸収帯.
- 半最大全幅 (FWHM) は約19.4cm−1.4cmである.
- バンド強度は,1.23 x 10−22 と 5.25 x 10−22 cm/molecule.の間で推定されています.
結論:
- 観測されたスペクトルの特徴は,既知のWD特性と一致しています.
- この検出は,大気と気候モデルのための重要なデータを提供します.
- 大気中のプロセスにおける水ダイマーの役割に関する理解を深める.
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