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The design and performance of a new Compton-suppressed HPGe and charged-particle array, CLARION2-TRINITY, are described. The TRINITY charged-particle array is comprised of 64 Cerium-doped Gadolinium Aluminium Gallium Garnet (GAGG:Ce) crystals configured into five rings spanning 7-54 degrees, and two annular silicon detectors that can shadow or extend the angular coverage to backward angles with minimal $\gamma$-ray attenuation. GAGG:Ce is a non-hygroscopic, bright, and relatively fast scintillator with a light distribution well matched to SiPMs. Count rates up to 40 kHz per crystal are sustainable. Fundamental characteristics of GAGG:Ce are measured and presented, including light- and heavy-ion particle identification (PID) capability, pulse-height defects, radiation hardness, and emission spectra. The CLARION2 array consists of up to 16 Compton-suppressed HPGe Clover detectors ($\approx4\%$ efficiency at 1 MeV) configured into four rings (eight HPGe crystal rings) using a non-Archimedean geometry that suppresses back-to-back coincident 511-keV gamma rays. The entire array is instrumented with 100- and 500-MHz (14 bit) waveform digitizers which enable triggerless operation, pulse-shape discrimination, fast timing, and pileup correction. Finally, two examples of experimental data taken during the commissioning of the CLARION2-TRINITY system are given: a PID spectrum from $^{16}$O + $^{18}$O fusion-evaporation, and PID and Doppler-corrected $\gamma$-ray spectra from $^{48}$Ti + $^{12}$C Coulomb excitation., Comment: 14 pages, 21 figures

The resoneut detector setup is described, which was developed for resonance spectroscopy using (d,n) reactions with radioactive beams in inverse kinematics and at energies around the Coulomb barrier. The goal of experiments with this setup is to determine the spectrum and proton-transfer strengths of the low-lying resonances, which have an impact on astrophysical reaction rates. The setup is optimized for l = 0 proton transfers in inverse kinematics, for which most neutrons are emitted at backward angles with energies in the 80–300 keV range. The detector system is comprised of 9 p-terphenyl scintillators as neutron detectors, two annular silicon-strip detectors for light charged particles, one position-resolving gas ionization chamber for heavy ion detection, and a barrel of NaI-detectors for the detection of γ -rays. The detector commissioning and performance characteristics are described with an emphasis on the neutron-detector components.

An active target detector array, ANASEN, has been developed for nuclear reaction studies with rare isotope beams at low energies. It aims at measurements of the excitation functions for proton and α - particle elastic and inelastic scattering and direct measurements of ( α , p) reactions with exotic nuclei in inverse kinematics. ANASEN is composed of three types of charged particle detectors. The length of the active area is 340 mm and the total covered area is 1300 cm 2 (almost 3 π steradian solid angle coverage) providing high efficiency for experiments with low intensity radioactive beams. A mix of 78 conventional electronics channels (for Proportional Counter and CsI-detectors) and 480 dedicated high-density ASICs electronics channels for the silicon detector are used for readout.

Measuring the fusion excitation function for an isotopic chain of projectile nuclei provides a stringent test of a microscopic description of fusion. We report the first measurement of the fusion excitation function at near-barrier energies for the 19 O + 12 C system. The measured excitation function is compared with the fusion excitation function of 18 O + 12 C. A significant enhancement in the fusion probability of 19 O ions with a 12 C target as compared to 18 O ions is observed. The experimental cross-sections observed at near-barrier energies are compared with a state-of-the-art microscopic model.

Particle gamma-ray angular correlation measurements have been used to study the spin alignment and magnetic-substate population parameters for the 2 + 1 (4.443 MeV) state in 12 C, populated in the 12 C ( 12 C , 12 C [0 + 2 ]) 12 C (2 + 1 ) inelastic scattering reaction in the vicinity of a prominent, narrow peak in the scattering excitation function. The data show a strong alignment of the spin with the orbital angular momentum, and suggest that the cross section peak corresponds to a spin 14 + resonance at E c.m. =28.0 MeV. This energy is close to that where a strong peak is also observed in the 0 + 1 +0 + 2 excitation function. A comparison between the data for these two channels lends some support to recent theoretical calculations of resonance behavior for angular-momentum-mismatched channels in 12 C + 12 C inelastic scattering.

Entry distributions in angular momentum and excitation energy have been measured for several very proton-rich isotopes of Pt and Au. This is the first systematic study of the energy-spin phase space for nuclei near and beyond the proton drip line. Comparisons are made between the distributions associated with proton-unbound Au nuclei and more stable Pt isobars. In 173 Au the first evidence is seen for the limits of excitation energy and angular momentum which a nucleus beyond the proton drip line can sustain.

An automatic gain-matching method has been developed for the energy calibrations of the 32 segments of a large-volume germanium detector. The method calibrates the small-volume segments relative to the central contact, which collects the charge from the total germanium crystal volume and can be efficiently calibrated with known sources. The method presented here can employ photons of arbitrary energy. With the use of in-beam γ-rays for segment calibrations it presents an efficient way to perform continuous energy calibrations in experiments.

An in-beam experiment with the subcoulomb reaction 209Bi(3He, d*γγ)210Po at 20.5 MeV was performed with two Euroball Cluster detectors in Cologne. It closed the gap between the low energy levels of the level-scheme and the high energy levels found in 209Bi(3He, d)210Po and 208Pb(4He, t)210Po particle experiments. New branchings have been found and the (3He, d*γγ) reaction below the coulomb-barrier has been used successfully.

We discuss the identification and properties of the states that belong to the highly clustered rotational band in A=10 nuclei, 10Be, 10B(T=1) and 10C. The band is of interest because it may correspond to an exotic α:nn:α configuration.

In125Xe eight lowlying band structures of positive parity were established via the122Te(α, n) reaction by means of in-beamγ-ray spectroscopy using a setup of 6 compton suppressed germanium detectors. The systematics of the related quasi- ′s′1/2, ′d′3/2, and ′g′7/2 bands with the variation of the fermi level in the triaxially deformed region from125Xe to129Xe is discussed.

A nuclear resonance fluorescence experiment with two highly efficient EUROBALL Cluster detectors has been performed on the γ -soft nucleus 194 Pt. Dipole excitations were observed between 2 and 4 MeV excitation energy. They are tentatively interpreted as the main fragments of the scissors mode based on the measured excitation strengths and a comparison to microscopic calculations in the framework of the quasiparticle random phase approximation (QRPA). The data indicate large differences to the neighbouring isotope 196 Pt: a doubling of the observed dipole strength and a shift of the energy centroid by about 600 keV. None of the currently available models is able to reproduce these features consistently in both nuclei.

High spin states in 167 Lu were populated through the 123 Sb( 48 Ca, xn ) reaction at 203 MeV. Four, presumably triaxial, strongly deformed (TSD) bands have been found in this nucleus. Several transitions linking an excited TSD band (TSD2) to the lowest (yrast) TSD band (TSD1) were observed. The electromagnetic properties of the connecting transitions have been investigated. Evidence for the assignment of TSD2 as a wobbling mode built on TSD1 is presented. This assignment is based on comparisons of the experimental data to theoretical calculations. The wobbling mode of excitation is an unambiguous signal of a stable triaxial deformation associated with these bands.

Excited structures in the neutron-deficient nucleus 179 Hg have been established for the first time using the Gammasphere spectrometer in conjunction with the fragment mass analyzer. Competing states originating from three different minima associated with nearly spherical, oblate, and prolate deformations were found. This result can be contrasted with the situation in heavier odd-mass Hg isotopes where only two minima (oblate and prolate) have been seen. The implications of these three shapes at low spin and excitation energy are discussed in the general context of shape coexistence in this mass region.

Three, possibly four, regularly spaced rotational bands with large dynamic moments of inertia have been identified in 174 Hf. Their properties are consistent with known triaxial superdeformed bands of the Lu/Hf region. Calculations predict substantial triaxial deformation ( γ ≈±17°) for 174 Hf structures with deformation ϵ 2 ≈0.45, despite the fact that 174 Hf is eight neutrons away from the previously established N =94 triaxial superdeformed gap. Shell gaps at N =100 and 106 with γ ⩾15° are predicted for ϵ 2 ≈0.45, and are most likely responsible for the calculated TSD minima in 174 Hf.