Producing long-lived $2^3\text{S}$ Ps via $3^3\text{P}$ laser excitation in magnetic and electric fields
S. Aghion, C. Amsler, M. Antonello, A. Belov, G. Bonomi, R. S. Brusa, M. Caccia, A. Camper, R. Caravita, F. Castelli, G. Cerchiari, D. Comparat, G. Consolati, A… 展开作者
S. Aghion, C. Amsler, M. Antonello, A. Belov, G. Bonomi, R. S. Brusa, M. Caccia, A. Camper, R. Caravita, F. Castelli, G. Cerchiari, D. Comparat, G. Consolati, A. Demetrio, L. Di Noto, M. Doser, C. Evans, M. Fani, R. Ferragut, J. Fesel, A. Fontana, S. Gerber, M. Giammarchi, A. Gligorova, F. Guatieri, P. Hackstock, S. Haider, A. Hinterberger, H. Holmestad, A. Kellerbauer, O. Khalidova, D. Krasnicky, V. Lagormarsino, P. Lansonneur, P. Lebrun, C. Malbrunot, S. Mariazzi, J. Marton, V. Matveev, Z. Mazzotta, S. R. Muller, G. Nebbia, P. Nedelec, M. Oberthaler, D. Pagano, L. Penasa, V. Petracek, F. Prelz, M. Prevedelli, B. Rienaecker, J. Robert, O. M. Rohne, A. Rotondi, H. Sandacker, R. Santoro, L. Smestad, F. Sorrentino, G. Testera, I. C. Tietje, M. Vujanovic, E. Widmann, P. Yzombard, C. Zimmer, J. Zmeskal, N. Zurlo
Producing positronium (Ps) in the metastable $2^3\text{S}$ state is of interest for various applications in fundamental physics. We report here about an experiment in which Ps atoms are produced in this long-lived state by spontaneous radiative decay of Ps excited to the $3^3\text{P}$ level manifold. The Ps cloud excitation is obtained with a UV laser pulse in an experimental vacuum chamber in presence of guiding magnetic field of 25 mT and an average electric field of 300 V/cm. The indication of the $2^3\text{S}$ state production is obtained from a novel analysis technique of single-shot positronium annihilation lifetime spectra. Its production efficiency relative to the total amount of formed Ps is evaluated by fitting a simple rate equations model to the experimental data and found to be $ (2.1 \pm 1.3) \, \% $.
On-line Excited-State Laser Spectroscopy of Trapped Short-Lived Ra$^+$ Ions
作为一个单一的捕获Ra $^+$离子的原子宇称破坏实验的重要一步，激光光谱实验进行了与在线产生的短寿命$^{212,213,214}$ Ra $^+$离子。测量了$^{213}$ Ra $^+$中$6\,^2$ D $_{3/2}$ \，-\，$7\,^2$ P $_{1/2}$和$6\,^2$ D $_{3/2}$ \，-\，$7\,^2$ P $_{3/2}$跃迁的同位素位移和$7\,^2$ S $_{1/2}$和$6\,^2$ D $_{3/2}$态的超精细结构常数。这些值为所需的原子理论提供了基准。通过光学搁置测量亚稳态$6\,^2$ D $_{5/2}$状态的寿命的下限$232(4)$ ms。
Isotope Shifts of the $6d\,^2$D$_{3/2}\,$ - $7p\,^2$P$_{1/2}\,$ Transition in Trapped Short-Lived $^{209-214}$Ra$^+$
在线性Paul阱中进行了短寿命镭同位素的激光光谱学研究。测量了$^{209-214}$ Ra $^+$中$6d\,^2$ D $_{3/2}\,$-$7p\,^2$ P $_{1/2}\,$跃迁的同位素位移，它对原子波函数的短程部分很敏感。这些结果为提高原子结构计算的精度提供了必要的实验依据。这是必不可少的宇称破坏Ra $^+$旨在确定弱混合角。
DEVCOM Army Research Laboratory South（美国陆军研发司令部南实验室）；Department of Physics, The American University（美国大学物理系）；General Technical Services（通用技术服务公司）；Department of Physics, Center for Complex Quantum Systems, The University of Texas at Austin（德克萨斯大学奥斯汀分校复杂量子系统中心物理系）；DEVCOM Army Research Laboratory（美国陆军研发司令部实验室）
Towards Collinear Laser Spectroscopy of Radioactive Molecules Utilizing In-trap Produced Molecular Ion Beam
School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University（北京大学物理学院与核物理与技术国家重点实验室）；Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所）
Study of the magnetic octupole moment of $^{173}$Yb using collinear laser spectroscopy
用三种不同的偶极跃迁测量了中性Yb中$^3$ P $^{\circ}_2$态的超精细常数。这个状态最近被证明有一个比较大的超精细磁八极分裂，因此一个令人困惑的大磁八极矩。该测量是使用共线激光光谱学在快速原子束上进行的，这提供了一种直接的途径来探测具有高分辨率的长寿命亚稳态原子态。从所有三条线的综合分析中，我们没有发现$^{173}$ Yb的非零八极矩的显著证据。
