Related papers: Nuclear clocks for testing fundamental physics
The rapid increase in accuracy and stability of optical atomic clocks compared to the caesium atomic clock as primary standard of time and frequency asks for a future re-definition of the second in the International System of Units (SI).…
Excitation of the anomalously low lying nuclear isomer $^{229m}$Th$(3/2^+, 8.28 \pm 0.17$ eV) in the process of inelastic electron scattering is studied theoretically in the framework of the perturbation theory for the quantum…
Present and prospective fundamental symmetry tests with nucleons, nuclei and atoms are probing for possible new physics at the TeV scale and beyond. These ongoing and proposed table-top as well as accelerator-based experiments are thus a…
The nuclear isomeric state $^{229m}$Th with an exceptionally low excitation energy makes the $^{229}$Th isotope a crucial candidate for nuclear clocks and many other applications. Efficient and controllable production of $^{229m}$Th is…
The 7.6 eV electromagnetic transition between the nearly degenerate ground state and first excited state in the Th-229 nucleus may be very sensitive to potential changes in the fine-structure constant, $\alpha = e^2/\hbar c$. However, the…
Nuclear physics tests of parity- and time-reversal invariance have both shaped the development of the Standard Model and provided key tests of its predictions. These studies now provide vital input in the search for physics beyond the…
Current state-of-the-art frequency standards are passive optical atomic clocks where the frequency of an optical resonator is stabilized to a narrow atomic transition. Passive clocks have achieved unprecedented stabilities of 6.6 x 10--19…
We perform detailed calculations of the electronic structure of the Os$^{16+}$ ion and demonstrate that it has several metastable states which can be used for very accurate optical clocks. The clocks are highly sensitive to manifestations…
High accuracy measurements in M\"ossbauer transitions open up the possibility to use them in the search for temporal and spatial variation of the fine-structure constant $\alpha$, quark mass $m_q$, and dark matter field which may lead to…
The total mass density of the Universe appears to be dominated by dark matter. However, beyond its gravitational interactions at the galactic scale, little is known about its nature. Extensions of the quantum electrodynamics Lagrangian with…
We demonstrate that several metastable excited states in Hf$~$II, Hf$~$IV and W$~$VI ions may be good clock states since they are sufficiently long-living and are not sensitive to the perturbations. Cooling E1 transitions are available.…
$^{229}$Th is the only known nucleus with an excited state that offers the possibility for a direct laser excitation using existing laser technology. Its excitation energy has been measured indirectly to be 7.8(5) eV ($\approx$160 nm). The…
A sharp resonance line that appears in three-photon transitions between the $^{1}S_{0}$ and $^{3}P_{0}$ states of alkaline earth and Yb atoms is proposed as an optical frequency standard. This proposal permits the use of the even isotopes,…
Optical atomic clocks using highly-charged ions hold an intriguing promise of metrology at the 19th significant figure. Here we study transitions within the $4f^{12}$ ground-state electronic configuration of highly charged ions. We consider…
The paper considers a principal possibility of creating a nuclear light source of the vacuum ultra violet (VUV) range based on the $^{229}$Th nucleus. This nuclear light source can help to solve two main problems -- excitation of the…
There exist in nature a few nuclear isomers with very low (eV) excitation energies, and the combination of low energy and narrow width makes them possible candidates for laser-based investigations. The best candidate is the lowest-energy…
Atomic clocks have been transformational in science and technology, leading to innovations such as global positioning, advanced communications, and tests of fundamental constant variation. Next-generation optical atomic clocks can extend…
We estimate the range of the radiative lifetime and energy of the anomalous, low-energy $3/2^+(7.8 \pm 0.5$ eV) state in the $^{229}$Th nucleus. Our phenomenological calculations are based on the available experimental data for the…
Recent advances in optical atomic clocks and optical time transfer have enabled new possibilities in precision metrology for both tests of fundamental physics and timing applications. Here we describe a space mission concept that would…
One of the primary goals of nuclear physics is providing a complete description of the structure of atomic nuclei. While mean-field calculations provide detailed information on the nuclear shell structure for a wide range of nuclei, they do…