The 25th AGATA week and ACC Meeting

Session

ACC 3

16 sept. 2025, 09:00

SB1 Main Lecture (GSI Helmholtzzentrum für Schwerionenforschung GmbH) (GSI - Germany)

69. (online) Report on the AGATA experiment number 23.003

Jakub Skowronski

16/09/2025 09:00

The lifetime of the 6.793 MeV subthreshold state in 15O plays a central role in constraining the astrophysical S-factor of the 14N(p,γ)15O reaction, the slowest process in the CNO cycle. This state has long been the source of large uncertainties in extrapolations to stellar energies, and previous lifetime measurements were unable to resolve the problem due to limited sensitivity. The...

61. Lifetime measurements for the study of intruder states towards the island of inversion along the N = 20 shell closure

Raquel Nicolás Del Álamo (INFN Padova and Università degli studi di Padova)

16/09/2025 09:20

Lifetime measurements are commonly used to unravel the nature and properties of nuclear states, as they are closely related to transition probabilities, which provide information on the nuclear wave functions. The experiment presented here aimed to study the interplay of spherical (0 ℏω) and intruder (2 ℏω) configurations in the low-lying states of isotopes on the edge of the N=20 island of...

60. Report on 238U(22Ne, x) and 238U(26Mg, x) to approach the Island of Inversion at N=20

Floris Drent (GSI)

16/09/2025 09:40

In this presentation, we report on our current status of the analysis and preliminary results of two AGATA-PRISMA experiments performed at Laboratori Nazionali di Legnaro, consisting of a $^{22}$Ne and $^{26}$Mg beam emitted upon an $^{238}$U target. AGATA is coupled with mass spectrometer PRISMA for ion identification and γ-ray coincidence. In both experiments, the $^{238}$U target is backed...

70. Excited States Lifetime measurements in neutron-rich Ca, Ar isotopes

Giuseppe Andreetta (INFN e Laboratori Nazionali di Legnaro)

16/09/2025 10:00

The region around doubly magic $^{48}$Ca is a cornerstone of our understanding of nuclear structure, characterized by the appearance of subshell closures at N=32 and 34 [1], and by the gradual disappearance of N=28 shell closure below Z=20 [2]. However, several experimental findings have challenged this understanding. Large charge and matter radii were found in $^{51-53}$Ca [3,4], showing...

67. Report on the experiment 22.101: Nuclear structure studies of neutron-rich isotopes in the vicinity of Z=28 and N=40

RUTH MICAELA ILLICACHI GUAMAN (IFIC-CSIC-UV)

16/09/2025 10:20

The experiment 22.101 is a joint experiment to address four different physics cases devoted to studying the physics of the $\nu g_{9/2}$ beyond $N = 40$. These are aimed at investigating:
• Collectivity and seniority conservation in the $\nu g_{9/2}$ orbital
• Shape coexistence and octupole vibrations in $^{68}$Ni
• Island of inversion and the role of intruders at $N ∼ 40$

For these...

71. (online) Shape coexistence in $^{52}$Cr: lifetime measurement of the 0$_2^+$ and the 4$_1^+$ states

Sara Pigliapoco (UniPD and INFN-PD)

16/09/2025 10:40

Coexistence between spherical and deformed shapes is largely found in and near semi-magic or doubly-magic nuclei.
The region between the doubly-magic $^{48}$Ca and $^{56}$Ni nuclei is predicted to present phenomena of shape coexistence, although experimental information on E0 and E2 transition strengths connecting deformed and spherical configurations remains rather limited. In $^{52}$Cr...