378 citations · 3.2k across the 86 of their papers we have counts for
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Excitation of the Th nucleus by the hole in the inner electronic shells
M. G. Kozlov, A. V. Oleynichenko, D. Budker +6
The Th nucleus has a long-lived isomeric state at 8.338(24) eV [Kraemer et al, Nature, \textbf{617}, 706 (2023)]. This state is connected to the ground state by an M1…
Contribution of negative-energy states to multipolar polarizabilities of the Sr optical lattice clock
S. G. Porsev, M. G. Kozlov, M. S. Safronova
We address the problem of lattice light shifts in the Sr clock caused by multipolar M1 and E2 atom-field interactions. We presented a simple but accurate formula for the magnetic-d…
The Bohr-Weisskopf effect in the potassium isotopes
Yu. A. Demidov, M. G. Kozlov, A. E. Barzakh +1
The magnetic hyperfine structure constants have been calculated for low-lying levels in neutral potassium atom taking into account the Bohr--Weisskopf (BW) and Breit--Rosenthal (BR…
Using parity-nonconserving spin-spin coupling to measure the Tl nuclear anapole moment in a TlF molecular beam
John W. Blanchard, Dmitry Budker, David DeMille +2
An experiment utilizing a TlF molecular beam is being developed by the CeNTREX collaboration to search for hadronic interactions that violate both time-reversal (T) and parity (P)…
Bremsstrahlung on noble gases at low energies
A. I. Milstein, S. G. Salnikov, M. G. Kozlov
A detailed analysis of the bremsstrahlung spectrum at nonrelativistic electron scattering on argon and xenon is carried out. It is shown that the approximate formulas widely used f…
Combination of the Perturbation Theory with Configuration Interaction Method
M. G. Kozlov, I. I. Tupitsyn, A. I. Bondarev +1
Present atomic theory provides accurate and reliable results for atoms with a small number of valence electrons. However, most current methods of calculations fail when the number…
New Measurement Resolves Key Astrophysical Fe XVII Oscillator Strength Problem
Steffen Kühn, Charles Cheung, Natalia S. Oreshkina +19
One of the most enduring and intensively studied problems of X-ray astronomy is the disagreement of state-of-the art theory and observations for the intensity ratio of two Fe XVII…
Laser Spectroscopy of the yP states of Cr I
E. B. Norrgard, D. S. Barker, S. P. Eckel +5
Here we report measured and calculated values of decay rates of the 3d(D)4s4p(P)\ yP states of Cr I. The decay rates are measured usin…
Precision calculation of hyperfine constants for extracting nuclear moments of 229Th
S. G. Porsev, M. S. Safronova, M. G. Kozlov
Determination of nuclear moments for many nuclei relies on the computation of hyperfine constants, with theoretical uncertainties directly affecting the resulting uncertainties of…
Probing fast oscillating scalar dark matter with atoms and molecules
Dionysios Antypas, Oleg Tretiak, Ke Zhang +5
Light scalar Dark Matter with scalar couplings to matter is expected within several scenarios to induce variations in the fundamental constants of nature. Such variations can be se…
Atomic calculations of hyperfine structure anomaly in gold
Yu. A. Demidov, E. A. Konovalova, R. T. Imanbaeva +2
The magnetic hyperfine structure constants have been calculated for low-lying levels in neutral gold atom and gold-like ion of mercury taking into account Bohr--Weisskopf (BW) effe…
Predicting quasibound states of negative ions
M. S. Safronova, C. Cheung, M. G. Kozlov +3
We demonstrated the accurate prediction of a quasibound spectrum of a negative ion using a novel high-precision theoretical approach. We used La as a test case due to a recent…
Detection of missing low-lying atomic states in actinium
Ke Zhang, Dominik Studer, Felix Weber +10
Two lowest-energy odd-parity atomic levels of actinium, 7s^27p 2P^o_1/2, 7s^27p 2P^o_3/2, were observed via two-step resonant laser-ionization spectroscopy and their respective ene…
Calculation of hyperfine magnetic anomaly in many-electron atoms
E. A. Konovalova, Yu. A. Demidov, M. G. Kozlov
The precision measurements of the ratio of hyperfine structure constants for and states allow us to estimate the difference between hyperfine magnetic anomalies…
Accurate prediction of clock transitions in a highly charged ion with complex electronic structure
C. Cheung, M. S. Safronova, S. G. Porsev +3
We have developed a broadly-applicable approach that drastically increases the ability to accurately predict properties of complex atoms. We applied it to the case of Ir, w…
Fast apparent oscillations of fundamental constants
Dionysios Antypas, Dmitry Budker, Victor V. Flambaum +3
Precision spectroscopy of atoms and molecules allows one to search for and to put stringent limits on the variation of fundamental constants. These experiments are typically interp…
High Resolution Photoexcitation Measurements Exacerbate the Long-Standing Fe XVII Oscillator Strength Problem
Steffen Kühn, Chintan Shah, José R. Crespo López-Urrutia +29
For more than 40 years, most astrophysical observations and laboratory studies of two key soft x-ray diagnostic transitions, and , in Fe XVII ions found oscillator…
Dependence of atomic parity-violation effects on neutron skins and new physics
A. V. Viatkina, D. Antypas, M. G. Kozlov +2
We estimate the relative contribution of nuclear structure and new physics couplings to the parity non-conserving spin-independent effects in atomic systems, for both single isotop…
Fast configuration-interaction calculations for nobelium and ytterbium
V. A. Dzuba, V. V. Flambaum, M. G. Kozlov
We calculate excitation energies for low states of nobelium, including states with open subshell. An efficient version of the many-electron configuration-interaction method fo…
Hyperfine induced transitions 1S0 - 3D1 in Yb
M. G. Kozlov, V. A. Dzuba, V. V. Flambaum
Parity violation experiment in Yb is made on the strongly forbidden M1 transition 6s^2 1S0 \to 5d6s 3D1. The hyperfine mixing of the 5d6s 3D1 and 5d6s 3D2 levels opens E2 channel,…
Sensitivity coefficients to variation of fundamental constants
M. G. Kozlov, D. Budker
Atoms and molecules can serve as sensitive probes of a possible variation of the fine structure constant and electron-to-proton mass ratio . Two types of sensitivity coeffic…
Highly charged ions: optical clocks and applications in fundamental physics
M. G. Kozlov, M. S. Safronova, J. R. Crespo López-Urrutia +1
Recent developments in frequency metrology and optical clocks have been based on electronic transitions in atoms and singly charged ions as references. These systems have enabled r…
Constraints on exotic spin-dependent interactions between matter and antimatter from antiprotonic helium spectroscopy
Filip Ficek, Pavel Fadeev, Victor V. Flambaum +4
Heretofore undiscovered spin-0 or spin-1 bosons can mediate exotic spin-dependent interactions between standard-model particles. Here we carry out the first search for semileptonic…
Atomic properties of actinide ions with particle-hole configurations
M. S. Safronova, U. I. Safronova, M. G. Kozlov
We study the effects of higher-order electronic correlations in the systems with particle-hole excited states using a relativistic hybrid method that combines configuration interac…