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In recent decades, γ -ray spectroscopy has undergone a major technological leap forward, namely the technique of γ -ray tracking, and has attained a sensitivity that is two orders of magnitude larger than that provided by the former generation of Compton-shielded arrays. Indeed the gain is comparable with the achievements since the dawn of γ -ray spectroscopy. Such sensitivity can be further heightened by coupling γ -ray spectrometers to other detectors that record complementary reaction products such as light-charged particles for transfer reactions and scattered ions for Coulomb excitation measurements. Nucleon transfer reactions offer an excellent mean to probe the energies of shell model single-particle orbitals and to study migration in energy of these orbitals as we venture away from stability. Such measurements can also estimate the cross sections of processes relevant to stellar evolution and nucleosynthesis. The measurement of γ rays in coincidence with particles provides also information on the decay channel for unbound systems, which constitutes a useful input for astrophysics and nuclear structure near the drip-lines. Coulomb-excitation studies make it possible to infer collective structure in nuclei and to extract deformation properties of, in particular, open-shell systems. Here, selected examples will be presented, highlighting the power of these types of experiments when γ -ray observation is included. The development of the experimental methods is reviewed, showing the results achieved before the advent of γ -ray tracking. Examples of more recent experiments that have successfully exploited γ -ray tracking with AGATA are then presented as showcases for the outstanding performance of the composite detection systems. The outlook for experiments using newly developed devices such as GRIT and other detectors such as SPIDER is described. [ABSTRACT FROM AUTHOR]

Multi-Nucleon Transfer (MNT) reactions have been used for decades as a reaction mechanism, in order to populate excited states in nuclei far from stability and to perform nuclear structure studies. Nevertheless, the development of set-ups involving high acceptance tracking magnetic spectrometers (mainly existing in Europe), coupled with the Advanced GAmma Tracking Array (AGATA) opens new possibilities, especially if they are used in conjunction with high-intensity stable beams or ISOL RIBs. In this article, we will discuss the capabilities of such set-ups aiming at different goals, including complete information in high-resolution spectroscopy as well as lifetime measurements. [ABSTRACT FROM AUTHOR]

7Example of different TKEL conditions for 92 Mo using the shortest target-to-degrader distance. a Doppler-corrected spectrum without a TKEL condition. b Condition on the low part of the TKEL. c More restrictive condition on the low part of the TKEL. d Condition on the high part of the TKEL. 10Simulated Doppler corrected -ray spectra using the velocity from PRISMA (after the degrader) for 50 Ca showing the DSAM and RDDS techniques. The original article can be found online at https://doi.org/10.1140/epja/s10050-023-01027-2. [Extracted from the article]

This work aims at presenting an alternative approach to the long standing problem of the B(E2) values in Sn isotopes in the vicinity of the N=Z double-magic nucleus 100Sn, until now predominantly measured with relativistic and intermediate-energy Coulomb excitation reactions. The direct measurement of the lifetime of low-lying excited states in odd-even Sn isotopes provides a new and precise guidance for the theoretical description of the nuclear structure in this region. Lifetime measurements have been performed in 105Sn for the first time with the coincidence Recoil Distance Doppler Shift technique. The lifetime results for the 7 / 2 1 + first excited state and the 11 / 2 1 + state, 2 + ( 104 Sn) ⊗ ν 1 g 7 / 2 multiplet member, are discussed in comparison with state-of-the-art shell model and mean field calculations, highlighting the crucial contribution of proton excitation across the core of 100Sn. The reduced transition probability B(E2) of the 11 / 2 1 + core-coupled state points out an enhanced staggering with respect to the B(E2; 2 1 + → 0 1 +) in the even-mass 104Sn and 106Sn isotopes. [ABSTRACT FROM AUTHOR]

The structure of 74Se at low energy was investigated via spectroscopy of internal conversion electrons at the INFN Legnaro National Laboratories (LNL). A set of internal K-conversion coefficients and monopole transition strengths was measured. A large ρ 2 (E 0 ; 2 2 + → 2 1 +) ⋅ 10 3 = 210 (130) value was deduced. This result, in addition to a low upper limit for the 0 3 + → 0 2 + electron transition, casts in doubt a simple interpretation of the 74Se low-lying structure, in particular the recently proposed spherical, vibrational character. New microscopic beyond-mean-field calculations generally agree with the experimental results and are capable of producing a large ρ 2 (E 0 ; 2 2 + → 2 1 +) value, even if still a factor ≈7 smaller than the experiment. Triaxiality and a complex shape-coexistence and mixing scenario seem responsible for this unexpected experimental result. [ABSTRACT FROM AUTHOR]