Istituto Nazionale di Ottica (INO)-Consiglio Nazionale Delle Ricerche (CNR), Comprensorio A. Olivetti, Via Campi Flegrei, Pozzuoli, Napoli 34-80078, Italy.
J Chem Phys. 2010 Oct 21;133(15):154317. doi: 10.1063/1.3493393.
The electric quadrupole fundamental (v=1←0) band of molecular deuterium around 3 μm is accessed by cavity ring-down spectroscopy using a difference-frequency-generation source linked to the Cs-clock primary standard via an optical frequency comb synthesizer. An absolute determination of the line position and strength is reported for the first two transitions (J=2←0 and J=3←1) of the S branch. An accuracy of 6×10(-8) is achieved for the line-center frequencies, which improves by a factor 20 previous experimental results [A. R. W. McKellar and T. Oka, Can. J. Phys. 56, 1315 (1978)]. The line strength values, measured with 1% accuracy, are used to retrieve the quadrupole moment matrix elements which are found in good agreement with previous theoretical calculations [A. Birnbaum and J. D. Poll, J. Atmos. Sci. 26, 943 (1969); J. L. Hunt, J. D. Poll, and L. Wolniewicz, Can. J. Phys. 62, 1719 (1984)].
采用腔衰荡光谱技术，利用与 Cs 钟主标准通过光频梳合成器相连接的差频产生源，研究了 3μm 左右的分子氘的电四极基（v=1←0）带。首次报道了 S 支的前两个跃迁（J=2←0 和 J=3←1）的线位置和强度的绝对确定。线中心频率的精度达到 6×10(-8)，比以前的实验结果提高了 20 倍[A. R. W. McKellar 和 T. Oka，Can. J. Phys. 56, 1315 (1978)]。用 1%的精度测量的线强值用于检索四极矩矩阵元素，这些元素与以前的理论计算吻合得很好[A. Birnbaum 和 J. D. Poll，J. Atmos. Sci. 26, 943 (1969)；J. L. Hunt、J. D. Poll 和 L. Wolniewicz，Can. J. Phys. 62, 1719 (1984)]。
