An overview of the mission and activities of the Nuclear Data Section of the International Atomic Energy Agency will be presented.
$\textbf{Historical overview}$. War and peace. The foundation of the International Atomic Energy Agency. Total neutron cross sections; $\textbf{matter radii}$; correlation with binding energy. Visit to Ioffe Institute: K$_\alpha$ Isotope Shift $\rightarrow$ $\delta r^2_{charge}$; other methods. Fine structure in $\textbf{charge radii}$ along isotopic series: shell effects, odd-even,...
Light nuclei exhibit many facets of nuclear structure, like halos and clustering, and are accessible for ab-initio nuclear structure calculations. The atomic structure of few-electron systems is well understood; it allows for accurate calculations of mass-shift and field-shift factors in non-relativistic quantum electrodynamics calculations (NR-QED) to extract precise nuclear charge radii...
The gyromagnetic $g$-factor of bound electrons in highly charged ions is ideal for testing quantum electrodynamics (QED) in the strongest electric fields. In heavy highly charged ions (HCI) the innermost electrons experiences electric fields exceeding $10^{15}$ V/cm that are otherwise unreachable in laboratories, but in a system still simple enough to enable high-precision theory...
The most precise value of the top-left corner element of the CKM matrix $V_{ud}$ is obtained from superallowed nuclear beta decays. Observed hints to a $2.5-3\sigma$ deficit in top-row CKM unitarity motivated a reanalysis of nuclear corrections. These latter use nuclear charge radii as input, and so do their uncertainties. An extraction of nuclear charge radii from atomic measurements entails...
For decades, muonic atom spectroscopy has provided absolute values of nuclear RMS radii. The recent restart of muonic atom measurements also led to refinements in theoretical predictions. In my presentation, I will show the latest results for heavy muonic atoms, comparing them with previous results and focusing on individual and overall uncertainties. Finally, I will discuss how recent...
A summary of isomers-shift measurements in the $Z=50$ region will be made related to the unique-parity $h_{11/2}$ shell.
$\textbf{Historical overview}$. War and peace. The foundation of the International Atomic Energy Agency. Neutron cross sections; $\underline{\rm matter \,radii}$; correlation with binding energy, mass dependence. Semiclassical model (NASA), matter radius derived. Visit to Ioffe Institute: K$_\alpha$ Isotope Shift $\rightarrow$ $\delta r^2_{charge}$; other methods. Tables of rms $\underline{\rm...
Finite nuclear size effects play an increasingly important role in precision atomic and nuclear physics. For example, they have been found to strongly affect the determination of the V_ud matrix element of the CKM matrix (arXiv:2309.16893)
Determining the absolute charge radius of some short-lived nucleus entails careful assembly of several pieces spanning different fields.
Measurements...
Once measurements have been converted into nuclear radii data, the challenge remains to combine these measurements into a consistent set of radii. Given the high number of radii (>800) to optimize and the tight coupling of radii from relative measurements, care must be taken to make a completely accurate non-linear approach feasible. radbase, an open-source set of Python codes, analyzes the...
Databases, web tools and applications developed at the Nuclear Data Section will be presented.
Isotope shift (IS) studies are traditionally used as tools to extract nuclear charge radii. Today their precise measurements also serve as the medium to probe physics supporting beyond the Standard Model (SM) of particle physics. These studies, however, demand high-accuracy calculations of IS constants that are combined with the IS measurements to infer nuclear charge radii as well as to trace...
The question about the relations of the nuclear charge radii to other experimental observables will be brought up and relations to nuclear quadrupole moments will be reflected on, illustrated with a few examples.
Over the last decade the CRIS experiment has measured utilised a high resolution resonance ionisation spectroscopy technique (CRIS) to measure charge radii in exotic nuclei. The low background and high efficiency has allowed the technique to measure short-lived exotic systems with production yields down ~10 atoms/second. This presentation will summarise the technical developments, challenges...
The isotope shifts of neutron-rich Sc and Zn isotopes have been measured in recent years using high-resolution laser spectroscopy techniques. By taking advantage of advanced atomic theory calculations, the nuclear charge radii of these two isotopic chains have been determined or re-evaluated, providing valuable insights into their nuclear structure. This contribution will present the measured...
Electron beam ion traps (EBITs) have proven to be a valuable tool for the spectroscopy of highly charged ions over the past few decades. Na-like and Mg-like ions are especially interesting in the context of nuclear charge radii sensitivity due to the enhanced overlap of their ground-state wave functions with the nucleus. Their strong 3s–3p emission can be measured with high precision...
