Meyer C, Becker A, Blaum K, Breitenfeldt C, George S, Göck J, Grieser M, Grussie F, Guerin E A, von Hahn R, Herwig P, Krantz C, Kreckel H, Lion J, Lohmann S, Mishra P M, Novotný O, O'Connor A P, Repnow R, Saurabh S, Schwalm D, Schweikhard L, Spruck K, Sunil Kumar S, Vogel S, Wolf A
Max-Planck-Institut für Kernphysik, D-69117 Heidelberg, Germany.
Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, D-17487 Greifswald, Germany.
Phys Rev Lett. 2017 Jul 14;119(2):023202. doi: 10.1103/PhysRevLett.119.023202.
Photodetachment thermometry on a beam of OH^{-} in a cryogenic storage ring cooled to below 10 K is carried out using two-dimensional frequency- and time-dependent photodetachment spectroscopy over 20 min of ion storage. In equilibrium with the low-level blackbody field, we find an effective radiative temperature near 15 K with about 90% of all ions in the rotational ground state. We measure the J=1 natural lifetime (about 193 s) and determine the OH^{-} rotational transition dipole moment with 1.5% uncertainty. We also measure rotationally dependent relative near-threshold photodetachment cross sections for photodetachment thermometry.
在冷却至10 K以下的低温存储环中，利用二维频率和时间相关的光剥离光谱，在20分钟的离子存储时间内，对一束OH⁻进行了光剥离测温。在与低水平黑体场达到平衡时，我们发现有效辐射温度接近15 K，约90%的离子处于转动基态。我们测量了J = 1的自然寿命（约193秒），并以1.5%的不确定度确定了OH⁻的转动跃迁偶极矩。我们还测量了用于光剥离测温的与转动相关的相对近阈值光剥离截面。
