相关论文: Internal conversion of the low energy $^{229m}$Th …
It is now well established that atomic nuclei composed of certain combinations of protons and neutrons can adopt reflection-asymmetric, or octupole-deformed, shapes at low excitation energy. These nuclei show promise in the search for a…
Latest experimental data on the properties of the 229Th nuclide isomer are analyzed. Deduced are the lifetime and the E2-fraction in its electromagnetic deexcitation, based on the latest experimental data concerning the isomer: its energy…
We report multiconfiguration Dirac-Hartree-Fock and relativistic configuration interaction calculations on the Thallium (Tl) electron affinity, as well as on the excited energy levels arising from the ground configuration of Tl$^-$. The…
A new approach to observe the radiative decay of the $^{229}$Th nuclear isomer, and to determine its energy and radiative lifetime, is presented. Situated at a uniquely low excitation energy, this nuclear state might be a key ingredient for…
An alternative method to determine the excitation energy of the $~^{229\rm{m}}\rm{Th}$ isomer via the laser-induced electronic bridge is investigated theoretically. In the presence of an optical or ultra-violet laser at energies that…
A low-energy nuclear transition in the isotope thorium-229 has been excited in thorium-doped crystals with laser light. This opens the perspective towards a highly stable and robust solid-state optical nuclear clock. The required laser…
The $^6$He beta decay and $^7$Be electron capture processes are studied using variational Monte Carlo wave functions, derived from a realistic Hamiltonian consisting of the Argonne $v_{18}$ two-nucleon and Urbana-IX three-nucleon…
We explore an unusual nature of chemical bonding of the thorium atom with a ring of six carbon atoms (hexagon) in novel carbon materials. Our ab initio calculations of Th-based metallofullerenes (Th@C60, Th@C20) and Th bound to benzene or…
We investigate the 1140 nm magnetic dipole transition of thulium atoms trapped in solid argon and neon. These solids can be straightforwardly grown on any substrate at cryogenic temperatures, making them prime targets for surface sensing…
Isomers with three- and five-nucleon-hole configurations have been established in $^{203}$Tl. These include newly identified levels with a three-nucleon structure: {\it I}$^{\pi }$ = (15/2$^{-}$) with {\it T}$_{1/2}$ = 7.9(5) ns, and {\it…
The energy interval between the ground and the P-wave excited states of the recently discovered positronium molecule Ps_2 is evaluated, including the relativistic and the leading logarithmic radiative corrections, E_P-E_S = 0.181 586 7(8)…
Laser spectroscopy of short-lived radium isotopes in a linear Paul trap has been performed. The isotope shifts of the $6d\,^2$D$_{3/2}\,$ - $7p\,^2$P$_{1/2}\,$ transition in $^{209-214}$Ra$^+$ were measured, which are sensitive to the short…
The low-energy isomeric transition in Thorium-229 offers a unique interface between nuclear and atomic physics, presenting a resource for quantum technologies that is notably resilient to environmental decoherence. While early experiments…
We perform coincidence measurements between $\alpha$ particles and $\gamma$ rays from a $^{233}$U source to determine the half-lives of the excited state in a $^{229}$Th nucleus. We first prove that the half-lives of 42.43- and 164.53-keV…
The possibility of refining the energy of the 8.36-eV 229mTh nuclear isomer -- the most likely candidate for the role of a nuclear frequency standard -- by means of resonant optical pumping is discussed. Attention is focused on considering…
Isomer depletion via the process of nuclear excitation by inelastic electron scattering is investigated theoretically. A comprehensive study on low-energy nuclear excitations by inelastic electron scattering is performed to analyze the…
We report measurements of the $^{115}$In $7p_{1/2}$ and $7p_{3/2}$ scalar and tensor polarizabilities using two-step diode laser spectroscopy in an atomic beam. The scalar polarizabilities are one to two orders of magnitude larger than for…
We have measured the 6s - 7p_{1/2,3/2} transition probabilities in atomic cesium using a direct absorption technique. We use our result plus other previously measured transition rates to derive an accurate value of the vector transition…
In the whole landscape of atomic nuclei, $^{229}$Th is currently the only known nucleus which could allow for the development of a nuclear-based frequency standard, as it possesses an isomeric state of just 7.6 eV energy above the ground…
Polonium isotopes having two protons above the shell closure at $Z=82$ show a wide variety of low-lying high-spin isomeric states across the whole chain. The structure of neutron-deficient isotopes up to $^{210}$Po ($N=126$) is well…