Related papers: High-Resolution Laser Spectroscopy of Long-Lived P…
Laser spectroscopy of the low lying $^1$P and $^3$D states in atomic barium has been performed. This work contributes substantially to the development of an effective laser cooling and trapping for heavy alkaline earth elements and aims in…
Laser spectroscopic studies on minute samples of exotic radioactive nuclei require very efficient experimental techniques. In addition, high resolving powers are required to allow extraction of nu- clear structure information. Here we…
The recent observation and measurement of the decay $Z_c(3900) \to \rho \eta_c$ provides the data on the relative strength of the pion and $\rho$ coupling in the corresponding transitions between exotic resonances and pure heavy quarkonium.…
Spectral lines belonging to the short-lifetime heavy radioactive elements up to Es ($Z$=99) have been found in the spectra of the Przybylski's star. We suggest that these unstable elements may be decay products of a "magic" metastable…
A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2015-2018 at $\sqrt{s}$ = 13 TeV from $pp$ collisions corresponding to an integrated luminosity of 139 fb$^{-1}$ are…
Laser spectroscopy of the Lamb shift (2S-2P energy difference) in light muonic atoms or ions, in which one negative muon $\mu^-$ is bound to a nucleus, has been performed. The measurements yield significantly improved values of the…
Hydrogen-like light muonic ions, in which one negative muon replaces all the electrons, are extremely sensitive probes of nuclear structure, because the large muon mass increases tremendously the wave function overlap with the nucleus.…
We report on the measurement of the isotope shifts of the $3d^74s \,\, a \, {}^5\!F_5 - 3d^74p \,\, z \, {}^5\!G^o_6$ Fe~I line at 358~nm between all four stable isotopes ${}^{54}$Fe, ${}^{56}$Fe, ${}^{57}$Fe and ${}^{58}$Fe, as well as the…
We report a precise measurement of hyperfine constants in the $\rm{D_1} $ line ($ \rm {5\,P_{1/2}} $ state) of the two stable isotopes of Rb. The motivation for the work is to try and resolve discrepant values that exists in the literature.…
Longstanding problems in the comparison of very accurate hyperfine-shift measurements to theory were partly overcome by precise measurements on few-electron highly-charged ions. Still the agreement between theory and experiment is…
This paper presents a search for massive charged long-lived particles produced in pp collisions at $\sqrt{s}=$ 13 TeV at the LHC using the ATLAS experiment. The dataset used corresponds to an integrated luminosity of 3.2 fb$^{-1}$. Many…
We report on improved isotope shift measurements of the isotopes $^{40,42,44,48}$Ca in the $4s\,^2 \rm{S}_{\frac{1}{2}} \rightarrow 4p\,^2\rm{P}_{\frac{3}{2}}$ (D2) transition using collinear laser spectroscopy. Accurately known isotope…
A new method for measuring a possible time dependence of the fine-structure constant ($\alpha$) is proposed. The method is based on the level-crossing in two-electron highly-charged ions facilitating resonance laser measurements of the…
We report on the absolute frequency determination of the 5s5p $^1P_1$ - 5s5d $^1D_2$ transition in atomic strontium, achieved through frequency comb-referenced laser-induced-fluorescence (LIF) spectroscopy. We excite the 5s$^2$ $^1S_0$ -…
The neutron-rich 6He and 8He isotopes exhibit an exotic nuclear structure that consists of a tightly bound 4He-like core with additional neutrons orbiting at a relatively large distance, forming a halo. Recent experimental efforts have…
We report laser-induced-fluorescence spectroscopy of the \({}^{1}S_{0}\rightarrow{}^{3}P_{1}\) intercombination transition in neutral zinc at \(307.6~\mathrm{nm}\). Isotope shifts are measured for all stable isotopes with kHz-level…
The result of a search for heavy long-lived charged particles produced in pp collisions at sqrt(s) = 7 TeV at the LHC is described. The data sample has been collected using the CMS detector and corresponds to an integrated luminosity of 5.0…
We demonstrate a technique for frequency measurements of UV transitions with sub-MHz precision. The frequency is measured using a ring-cavity resonator whose length is calibrated against a reference laser locked to the $D_2$ line of…
This talk gives an overview of the recent results on the precision spectroscopy of antiprotonic helium which was performed by the ASACUSA collaboration at the Antiproton Decelerator of CERN. The laser spectroscopy of energy levels of the…
We report measurements and theoretical calculations of the fine-structure splittings in all three $1s2s\,^3\!S_1\rightarrow\,1s2p\,^3\!P_{0,1,2}$ transitions in the heliumlike systems of the isotopes $^{12,13,14}$C. The metastable triplet…