Related papers: Critically Evaluated Atomic Data for Au IV Spectru…
We report on a precision measurement of the $(5\mathrm{p})^{5}6\mathrm{p} \, [1/2]_{0}\leftarrow (5\mathrm{p})^{6} \, ^{1}\mathrm{S}_{0}$ transition wavenumber of Xe by Doppler-free two-photon spectroscopy using…
Level energies, wavelengths, electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transition rates, oscillator strengths, and line strengths from combined relativistic configuration interaction and many-body…
Numerous accidental near-degeneracies exist between the $2\nu_2$ and $\nu_4$ rotation-vibration energy levels of ammonia. Transitions between these two states possess significantly enhanced sensitivity to a possible variation of the…
The identifications of Fe VII emission lines in the wavelength range 193-197 {\AA} are discussed in the light of new measurements of laboratory spectra and atomic data calculations. This region is of importance to studies of solar spectra…
This comment points out errors in the analysis of 61 magnetic hyperfine structure ($A$) constants of Co II energy levels by Fu et al. [JQSRT 2021, 107590]. The paper was published without full awareness of the extensive literature already…
We report a precise measurement of the isotope shifts in the $4^2$S$_{1/2} \rightarrow 3^2$D$_{3/2}$ electric quadrupole transition at 732~nm in $^{40 - 42,44,48}$Ca$^+$ via high-resolution laser spectroscopy of co-trapped ions, finding…
We report on the first experimental results for microwave spectroscopy of the hyperfine structure of antiprotonic He-3. Due to the helium nuclear spin, antiprotonic He-3 has a more complex hyperfine structure than antiprotonic He-4 which…
Energy levels and radiative rates are reported for transitions in Br-like W XL, calculated with the general-purpose relativistic atomic structure package ({\sc grasp}). Configuration interaction (CI) has been included among 46…
Rotationally resolved spectra of the C$^2\Sigma^+$-X$^2\Pi$ electronic system of the CH radical were measured using cavity ring-down spectroscopy in supersonically expanding, planar hydrocarbon plasma. The experimental conditions allowed…
Metastable levels in rhodium-like ions with the ground configuration $4p^{6}4d^{9}$ and the excited configurations $4p^{6}4d^{8}4f$ and $4p^{5}4d^{10}$ are investigated. The {\sl ab initio} calculations of the level energies, radiative…
A strong effort has been devoted to understand the physical origin of radio emission from low-luminosity AGN (LLAGN), but a comprehensive picture is still missing. We used high-resolution ($\le$1 arcsec), multi-frequency (1.5, 5.5, 9 and 14…
We characterize spectroscopic and coherence properties of the 1451.37 nm excited-state zero-phonon line (ZPL) between the $^{3}F_{4}$ and the $^{3}H_{4}$ manifolds of a thulium-doped yttrium aluminum perovskite (Tm$^{3+}$:YAlO$_3$) crystal…
Transition frequencies between low-lying energy levels in a single trapped $^{138}$Ba$^{+}$ ion have been measured with laser spectroscopy referenced to an optical frequency comb. By extracting the frequencies of one-photon and two-photon…
We describe experimental investigations on an optical frequency standard based on a laser cooled 171Yb+ ion confined in a radiofrequency Paul trap. The electric-quadrupole transition from the 2S1/2(F=0) ground state to the 2D3/2(F=2) state…
For the spectral analysis of high-resolution and high-signal-to-noise spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model-atmospheres are mandatory. These are strongly dependent on the reliability of the…
We measure the absolute frequency of seven out of the nine allowed transitions between the 2$^3${\it S} and 2$^3${\it P} hyperfine manifolds in a metastable $^3$He beam by using an optical frequency comb synthesizer-assisted spectrometer.…
We present new calculations for transition probabilities of Fe IV, with much more extensive datasets than heretofore available. The large-scale close coupling R-matrix calculations yield 1,798 LS bound states with n $\leq$ 11 and $l \leq$…
The rotational spectrum of the molecular ion HCNH+ is revisited using double-resonance spectroscopy in an ion trap apparatus, with six transitions measured between 74 and 445 GHz. Due to the cryogenic temperature of the trap, the hyperfine…
Collisions of Au on Au at incident energies of 150, 250 and 400 A MeV were studied with the FOPI-facility at GSI Darmstadt. Nuclear charge (Z < 16) and velocity of the products were detected with full azimuthal acceptance at laboratory…
The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity $|y_{ee}|<1$ in minimum-bias Au+Au…