Zakopane 2026 Conference on Nuclear Physics

We present recent results obtained in the $^{22}$Ne + $^{238}$U and $^{26}$Mg + $^{238}$U multi-nucleon transfer experiments performed within the current AGATA campaign at Laboratori Nazionali di Legnaro [1-3], aiming to explore the structural evolution of light nuclei towards the $N=20$ Island of Inversion [4]. Specifically, we focus on studying the evolution of quadrupole collectivity in even-even Ne and Mg isotopes, and on tracking negative-parity states from the fp shell in even-odd nuclei, locating excited intruder configurations toward the $N=20$ shell closure. The coupling between the AGATA $\gamma$ array and the PRISMA magnetic spectrometer allowed us to detect ion-$\gamma$ coincidences and to extract sub-picosecond lifetimes of excited states via the DSAM technique. In this work, level and decay schemes of $^{23-26}$Ne were extended and further characterized by $\gamma$-ray angular distributions. Preliminary lifetime measurements will also be discussed along with state-of-the-art calculations of quadrupole strengths, including very recent ab initio predictions [5-9].

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