Nuclear Shapes of Heavy Atoms and Proton-Emitting nuclei (NSHAPE)

By combining atomic, nuclear and particle physics techniques, I shall perform the experimental study of the shape of key atomic nuclei, to challenge our understanding of the nucleus. This combined effort will reach unprecedented sensitivity, precision and accuracy to determine the shape observables (charge radii, electric quadrupole moments) and compare them to state-of-the-art nuclear models (spherical shell model, density functional theory, ab initio models based on chiral effective field theory).

This programme will combine different techniques at various accelerator facilities where I employ and develop unique approaches and instrumentation:

- At CERN ISOLDE (Geneva, CH), high-resolution laser resonance ionization spectroscopy will be performed with the Resonant Ionization Laser Ion Source (RILIS) combined with the Perpendicularly-Illuminated Laser Ion Source and Trap (PI-LIST) to study the onset of octupole deformation and proceed towards the proton drip line with selected nuclei.

- At GANIL SPIRAL2 (Caen, FR), high-sensitivity laser resonance ionization spectroscopy will be performed in the supersonic gas jet of the gas cell at the focal plane of the Super Separator Spectrometer (S3) to study the most exotic isotopes not available at ISOLDE, reaching proton-unbound nuclei at the drip line.

- At PSI (Villigen, CH), muonic x-ray spectroscopy will be performed on key isotopes to measure absolute charge radii that are crucial to complete the analysis of the NSHAPE isotopes. This work will combine a strong experimental development in target production for muX, in the detector array, and in the analysis tools.

Combining the high-resolution laser spectroscopy and the high-accuracy from μx-ray spectroscopy is a unique programme that only NSHAPE can fully realize, providing radii and moments with unprecedented accuracy. From those results, I shall obtain a deeper understanding of the strong interaction at work in the nuclear medium.