Related papers: Precision study of 6p 2Pj - 8s 2S1/2 relative tran…
The linear polarization signals produced by scattering processes in strong resonance lines are rich in information on the magnetic and thermal structure of the chromosphere and transition region of the Sun and of other stars. A correct…
We report on measurements on the 5S-6P rubidium transition frequencies for rubidium isotopes with an absolute uncertainty of better than \SI{450}{kHz} for the 5S $\rightarrow$ 6P$_{1/2}$ transition and \SI{20}{kHz} for the 5S $\rightarrow$…
Energy levels, radiative rates and lifetimes are reported for 19 F-like ions with 55 $\le$ Z $\le$ 73, among 113 levels of the 2s$^2$2p$^5$, 2s2p$^6$, 2s$^2$2p$^4$3$\ell$, 2s2p$^5$3$\ell$, and 2p$^6$3$\ell$ configurations. The…
A new data set for the helicity-dependent differential cross section of the single-meson photoproduction reaction $\gamma p \to p \pi^{0}$ was obtained for the photon energy interval 150-400 MeV. The experiment was performed at the A2…
The hyperfine constants of the levels 2p2(3P)3s 4P_J, 2p2(3P)3p 4Po_J and 2p2(3P)3p 4Do_J, deduced by Jennerich et al. [Eur. Phys. J. D 40 (2006) 81] from the observed hyperfine structures of the transitions 2p2(3P)3s 4P_J - 2p2(3P)3p…
Using first-principles calculations, we identify magic wavelengths for the 2s-2p and 2s-3p transitions in lithium. The ns and np atomic levels have the same ac Stark shifts at the corresponding magic wavelength, which facilitates…
We exploit the process of asymmetry amplification by stimulated emission which provides an original method for parity violation (PV) measurements in a highly forbidden atomic transition. The method involves measurements of a chiral,…
Energies for the lowest 56 levels, belonging to the 3s$^2$3p, 3s3p$^2$, 3p$^3$, 3s$^2$3d, 3s3p3d, 3s$^2$4$\ell$ and 3s$^2$5$\ell$ configurations of Si II, are calculated using the {\sc grasp} (General-purpose Relativistic Atomic Structure…
The measurement by Pohl et al. [1] of the 2S_1/2^F=1 to 2P_3/2^F=2 transition in muonic hydrogen and the subsequent analysis has led to a conclusion that the rms charge radius of the proton differs from the accepted (CODATA [2]) value by…
A multi-detector array has been designed and constructed for the simultaneous measurement of energy- and angular correlations of electron-positron pairs. Experimental results are obtained over a wide angular range for high-energy…
We investigate the excitation of the 5D_{5/2} level in Rb atoms using counter-propagating laser beams, which are nearly resonant to the one-photon 5S_{1/2} - 5P_{3/2} and 5P_{3/2} - 5D_{5/2} transitions, ensuring that a sum of the optical…
Stimulated by the proton radius conundrum, measurements of the Lamb shift in various light muonic atoms are planned at PSI. The aim is to extract the rms charge radius with high precision, limited by the uncertainty in the nuclear…
We estimate the nuclear polarizability correction to atomic transition frequencies in various helium isotopes. This effect is non-negligible for high precision tests of quantum electrodynamics or accurate determination of the nuclear charge…
We report on hyperfine-resolved spectroscopic measurements of the electric-dipole forbidden 5$p_{3/2} \to 8p_{1/2}$ transition in a sample of ultracold $^{87}$Rb atoms. The hyperfine selection rules enable the weak magnetic-dipole (M1)…
We performed a reference-free measurement of the transition energies of the $1s 2p\,^1P\_1\to 1s^2 \,^1S\_0$ line in He-like argon, and of the $1s 2s^2 2p\,^1P\_1\to 1s^2 2s^2\,^1S\_0$ line in Be-like argon ions. The highly-charged ions…
We investigate nonresonant contributions to resonant Rayleigh scattering cross sections of atoms. The problematic nonresonant contributions set a limit to the accuracy to which atomic spectra determine energy levels. We discuss the…
We have completed measurements of two low-lying excited-state electric-dipole (E1) transition amplitudes in lead. Our measured reduced matrix elements of the $(6s^2 6p^2)^3P_1 \to (6s^2 6p7s)^3P_0$ transition at 368.3 nm and the 405.8 nm…
Magic wavelengthsfor the $7S_{1/2}-7P_{1/2,3/2}$ transitions in Fr were reported by Dammalapati \textit{et al.} in [Phys. Rev. A 93, 043407 (2016)]. These $\lambda_{\rm{magic}}$ were determined by plotting dynamic polarizabilities…
High-precision quasi-simultaneous collinear/anticollinear laser spectroscopy was performed to measure the $5s$ $^2S_{1/2}\rightarrow 5p$ $^2P_{1/2}$ (D1), the $5s$ $^2S_{1/2}\rightarrow 5p$ $^2P_{3/2}$ (D2), and the three $4d\rightarrow 5p$…
Accurate measurements of different transition frequencies between atomic levels of the electronic and hyperfine structure over time are used to investigate temporal variations of the fine structure constant $\alpha$ and the…