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Abdominal aortic aneurysm (AAA) is a highly lethal disease with progressive dilatation of the abdominal aorta accompanied by degradation and remodelling of the vessel wall due to chronic inflammation. Platelets are small anuclear cells that can release various inflammatory cytokines and biological response modulators when activated. In cardiovascular diseases, platelets are crucial for the inflammatory response but their role in AAA is poorly understood. However, both -experimental and clinical data-strongly suggest that platelet activation may be relevant for AAA formation and progression. Here, we find that platelets play a crucial role in promoting AAA through modulation of inflammation and degradation of the ECM. They are responsible for the up-regulation ofSPP1(osteopontin, OPN) gene expression in macrophages and aortic tissue, which triggers inflammation and remodeling. Further, enhanced platelet activation and pro-coagulant activity results in elevated gene expression of various cytokines,Mmp9andCol1a1in macrophages. Platelet depletion in experimental murine AAA reduced inflammation and ECM remodeling, with reduced elastin fragmentation and aortic diameter expansion. In conclusion, our data strongly supports the potential relevance of anti-platelet therapy to reduce AAA progression and rupture in AAA patients.

The ( α , α ′ γ ) reaction at E α = 136 MeV was used to study the electric dipole response in the open-shell vibrational nucleus 94Mo below the neutron-separation threshold. The coincidence experiment has been performed at the Kernfysisch Versneller Instituut in Groningen, The Netherlands, exploiting the Big-Bite Spectrometer and an array of large volume High-Purity Germanium (HPGe) detectors. Due to the excellent energy resolution and high selectivity to transitions stemming from the pygmy dipole resonance, singles α-scattering cross sections could be determined for individual electric dipole excitations between 4 and 8 MeV. For three of the excited low-lying J π = 1 − states in 94Mo a γ-decay branch into the J π = 2 1 + state could be observed. The experiment extends the systematic studies of the pygmy dipole resonance by real-photon scattering ( γ , γ ′ ) experiments and ( α , α ′ γ ) experiments. Recently, a ( γ , γ ′ ) experiment on 94Mo was performed at the Darmstadt High-Intensity Photon Setup at the S-DALINAC in Darmstadt, Germany, permitting the comparison of B ( E 1 ) ↑ strength distribution and α-scattering cross sections.

The B(E2) excitation strength of the first excited 2(+) state in even-even nuclei should directly correlate with the size of the valence space and maximize at mid-shell. A previously found saturation of B(E2) strengths in well-deformed rotors at mid-shell is tested through high-precision measurements of the lifetimes of the lowest-lying 2(+) states of the Hf-168 and W-174 rare earth isotopes. Measurements were performed using fast LaBr3 scintillation detectors. Combined with the recently remeasured B(E2; 2(1)(+) -> 0(1)(+)) values for Hf and W isotopes the new data remove discrepancies observed in the differentials of B(E2) values for these isotopes.

Background: One-phonon mixed-symmetry quadrupole excitations are a well-known feature of near-spherical, vibrational nuclei. Their interpretation as a fundamental building block of vibrational structures is supported by the identification of multiphonon states resulting from a coupling of fully-symmetric and mixed-symmetric quadrupole phonons. In addition, the observation of strong M1 transitions between low-lying 3(-) and 4(+) states has been interpreted as an evidence for one-phonon mixed-symmetry excitations of octupole and hexadecapole character. Purpose: The aim of the present study is to identify collective one-and two-phonon excitations in the heaviest stable N = 52 isotone Ru-96 based on a measurement of absolute M1, E1, and E2 transition strengths. Methods: Inelastic proton-scattering experiments have been performed at the Wright Nuclear Structure Laboratory (WNSL), Yale University, and the Institute for Nuclear Physics (IKP), University of Cologne. From the acquired proton-gamma and gamma gamma coincidence data we deduced spins of excited states, gamma-decay branching ratios, and multipole mixing ratios, as well as lifetimes of excited states via the Doppler-shift attenuation method (DSAM). Results: Based on the new experimental data on absolute transition strengths, we identified the 2(+) and 3(+) members of the two-phonon mixed-symmetry quintuplet (2(1,ms)(+) circle times 2(1,s)(+)). Furthermore, we observed strong M1 transitions between low-lying 3(-) and 4(+) states suggesting one-phonon symmetric andmixed-symmetric octupole and hexadecapole components in their wave functions, respectively. The experimental results are compared to sdg-IBM-2 and shell-model calculations. Conclusions: Both the sdg-IBM-2 and the shell-model calculations are able to describe key features of mixed-symmetry excitations of Ru-96. Moreover, they support the one-phonon mixed-symmetry hexadecapole assignment of the experimental 4(2)(+) state.

The NeuLAND detector at the R 3 B experiment at the future FAIR facility in Darmstadt aims to detect fast neutrons (0.2–1.0 GeV) with high time and spatial resolutions ( σ t 100 ps , σ x , y , z 1 cm ) . This task can be performed either with a scintillator or based on the multigap resistive plate chamber (MRPC) technology. Here, prototyping and test for an MRPC-based solution are discussed. In order to reach 90% detection efficiency, the final detector must consist of 50 consecutive MRPC stacks. Each stack contains a 4 mm thick anode made of iron converter material, with an additional 4 mm of converter material between two stacks. The secondary charged particles stemming from hadronic interactions of the high energetic neutrons in the converter will be detected in the MRPCs. As part of the ongoing development effort, a number of prototypes for this detector have been developed and built. They have been tested in experiments with a single-electron beam with picosecond resolution at the superconducting linac ELBE (Dresden, Germany). The results of the tests are presented here, and an outlook is given.

The Darmstadt High-Intensity Photon Setup (DHIPS) for photon-scattering and photodissociation experiments at the superconducting electron linear accelerator S–DALINAC has been improved. We report on its present performance. The developments include the installation of a segmented radiator for an online evaluation of the beam energy and the construction of a second photon-scattering setup with a Clover detector to deduce parity assignments. The enhancement of the existing photon-scattering setup with an additional 100% HPGe detector and some minor changes are described as well as the installation of two setups for photon-induced activation. In addition, we present a comparison of experimental data to Monte Carlo simulations using the codes Geant 3.21 and GEANT4.

We studied the two astrophysically interesting reactions 141 Pr ( α , n ) 144 Pm and 92 Mo ( p , γ ) 93 Tc with the activation method and with the in-beam method, respectively. The 141 Pr ( α , n ) 144 Pm experiment was performed at the cyclotron of the ‘Physikalisch Technische Bundesanstalt (PTB)’ in Braunschweig, Germany, and the reaction was studied within and just above the so-called Gamow window. In this proceedings, we present the experimental details of this measurement. The proton-capture reaction on the neutron-magic nucleus 92 Mo was studied at energies relevant for the astrophysical p process. The reaction was investigated by the in-beam technique using the γ -ray detector array HORUS (High efficient Observatory for γ -Ray Unique Spectroscopy) at the TANDEM ion accelerator at the University of Cologne. The preliminary experimental results are compared to data stemming from other measurements.

A new photon tagging spectrometer was built at the superconducting Darmstadt electron linear accelerator (S-DALINAC). The system is designed for tagging photons in an energy range from 6 to 20 MeV with the emphasis on best possible energy resolution and intensity. The absolute energy resolution of photons at 10 MeV is expected to be about 20 keV. With scintillating fibres as focal-plane detectors a maximum rate of tagged photons of 10 4 keV-1s-1 will be achieved. Detailed design studies including Monte Carlo simulations are presented, as well as results for the measured tagged photon energy profile of the system realized so far. This photon-tagging facility will allow to determine the photon absorption cross-sections as a function of excitation energy and to study the decay patterns of nuclear photo-excitations in great detail.

The low-lying positive- and negative-parity states in $^{168}\mathrm{Yb}$ have been investigated by means of the $(\ensuremath{\alpha},2\mathrm{n}\ensuremath{\gamma})$ fusion evaporation reaction. Using the coincidence method, the level scheme was corrected and extended up to 3 MeV, for both the positive- and negative-parity states. Using the new branching ratios determined in the present experiment, the $K$ quantum number was proposed for two negative-parity bands by direct comparison with the Alaga rule. Like in some other nuclei, one negative-parity band was established, decaying predominantly to the $\ensuremath{\gamma}$-vibrational band. In a second experiment, the lifetimes of the low-lying excited states up to ${J}^{\ensuremath{\pi}}={6}^{+}$ in the ground-state band were measured by using the in-beam fast-timing method with the Bucharest mixed high-purity germanium (HPGe) and ${\mathrm{LaBr}}_{3}$:Ce detector array using the triple-$\ensuremath{\gamma}$ coincidence method. Reduced $E2$ transition probabilities were extracted from the measured lifetimes and compared with the corresponding observables in neighboring isotopes, showing a smooth behavior with increasing mass. The positive- and negative-parity states as well as $E1$ and $E2$ transition probability ratios revealed by these experiments are compared with the interacting boson model in the $sd$ and $spdf$ boson space, and with the confined beta-soft rotor model, and are found to be in good agreement.

Background: Excitations with mixed proton-neutron symmetry have been previously observed in the $N=52$ isotones. Besides the well established quadrupole mixed-symmetry states (MSS), octupole and hexadecapole MSS have been recently proposed for the nuclei $^{92}$Zr and $^{94}$Mo. Purpose: The heaviest stable $N=52$ isotone $^{96}$Ru was investigated to study the evolution of octupole and hexadecapole MSS with increasing proton number. Methods: Two inelastic proton-scattering experiments on $^{96}$Ru were performed to extract branching ratios, multipole mixing ratios, and level lifetimes. From the combined data, absolute transition strengths were calculated. Results: Strong $M1$ transitions between the lowest-lying $3^-$ and $4^+$ states were observed, providing evidence for a one-phonon mixed-symmetry character of the $3^{(-)}_2$ and $4^+_2$ states. Conclusions: $sdg$-IBM-2 calculations were performed for $^{96}$Ru. The results are in excellent agreement with the experimental data, pointing out a one-phonon hexadecapole mixed-symmetry character of the $4^+_2$ state. The $\big< 3^-_1||M1||3^{(-)}_2\big>$ matrix element is found to scale with the $$ matrix element.

High resolution photon scattering experiments were performed at the 10 MeV bremsstrahlung facility of the electron accelerator S-DALINAC at TU Darmstadt to investigate the semi-magic N = 82 nuclei 138Ba, 140Ce, 142Nd and 144Sm. Energies and absolute strengths of dipole transitions below 10 MeV were determined in a model independent way. A concentration of electric dipole excitations exhausting up to 1% of the isovector E1 energy weighted sum rule is observed in all four nuclei around 6.5 MeV. Calculations in the framework of the Quasiparticle-Phonon Model (QPM) reproduce the gross experimental features.

The nucleus $^{154}\mathrm{Gd}$ is located in a region of the nuclear chart where rapid changes of nuclear deformation occur as a function of particle number. It was investigated using a combination of $\ensuremath{\gamma}$-ray scattering experiments and a $\ensuremath{\gamma}\ensuremath{\gamma}$-coincidence study following electron capture decay of $^{154}\mathrm{Tb}^{m}$. A novel decay channel from the scissors mode to the first excited ${0}^{+}$ state was observed. Its transition strength was determined to $B(M1;{1}_{sc}^{+}\ensuremath{\rightarrow}{0}_{2}^{+})=0.031(4){\ensuremath{\mu}}_{N}^{2}$. The properties of the scissors mode of $^{154}\mathrm{Gd}$ imply a much larger matrix element than previously thought for the neutrinoless double-$\ensuremath{\beta}$ decay to the ${0}_{2}^{+}$ state in such a shape-transitional region. Theory indicates an even larger effect for $^{150}\mathrm{Nd}$.

The nucleus (154)Gd is located in a region of the nuclear chart where rapid changes of nuclear deformation occur as a function of particle number. It was investigated using a combination of γ-ray scattering experiments and a γγ-coincidence study following electron capture decay of (154)Tb(m). A novel decay channel from the scissors mode to the first excited 0(+) state was observed. Its transition strength was determined to B(M1;1(sc)(+)→0(2)(+))=0.031(4)μ(N)(2). The properties of the scissors mode of (154)Gd imply a much larger matrix element than previously thought for the neutrinoless double-β decay to the 0(2)(+) state in such a shape-transitional region. Theory indicates an even larger effect for (150)Nd.

Background: The interplay between single-particle and collective excitations in the 30 ≤Z≤ 40 and 30 ≤N≤ 50 even-even isotopes has been examined in light of recent new measurements of magnetic moments of 41+, 22+, and 21+ states. Purpose: The g factors of the 41+ and 22+ states in the 72,74,76Ge isotopes have been measured for the first time and the g(21+) values have been remeasured. Methods: The transient field (TF) technique in inverse kinematics with a variety of targets has been applied, following Coulomb excitation of the relevant states. The data have been analyzed within the framework of the IBA-II model. Large-scale shell-model calculations have been performed within the p3/2,p1/2,f 5/2,g9/2 orbital space for both protons and neutrons with the JUN45 and JJ4B interactions. Results: The measured Ge g factors were compared to the g factors of the low-lying states of the neighboring Zn, Ge, Se, Kr, and Sr isotopes. The results were evaluated in the context of the systematics of g factors in the A∼80 region. Conclusions: The predictions based on the classic collective model and the interacting boson model IBA-II agree with the experimental results. No evidence for shell closure was found for neutrons at N=38 or N=40. © 2013 American Physical Society.

The HORUS spectrometer at the 10MV Tandem accelerator at the Institute for Nuclear Physics in Cologne consists of 14 high-purity germanium γ-detectors. To extend the experimental opportunities, the new silicon-detector array SONIC was designed, housing eight ΔE-E sandwich silicon detectors for ion spectroscopy. In order to process all 30 detector signals, the analog data acquisition was replaced by a digital one using the commercially available DGF-4C modules from the company XIA. The new data acquisition system was tested in two experiments.

Excited states in 74Se were populated following the e/β + decay of 74Br, mainly from the J=K=4, 13.8-keV β-decaying isomer. Off-beam γ-ray spectroscopy was performed with the array of Clover HPGe detectors at WNSL Yale. Many new transitions were observed and rigorous spin assignments were made based on γ-γ angular correlations. The β-decay strength was found to proceed almost entirely to a few high-lying states near 4500 keV, which are consistent with deformed two-quasineutron high-K configurations. These doorway states then provide an effective tool for populating and identifying the lower prolate structures. Once categorized, the low-lying states of 74Se can be described as a set of near-spherical vibrational levels mixing strongly with a spectrum of prolate states which have an unperturbed bandhead near 1350 keV. © 2013 American Physical Society.

6th Nuclear Physics in Astrophysics Conference (NPA), Lisbon, Portugal, 19 May 2013 - 24 May 2013; Journal of physics / Conference Series 665, 012034 (2016). doi:10.1088/1742-6596/665/1/012034, Published by IOP Publ., Bristol

Precise electromagnetic transition matrix elements in 10Be and 10C have provided surprisingly stringent tests of modern ab initio calculations using realistic nuclear forces. The analog transition in 10B can further constrain these new calculations and probe the symmetry of the wave functions across the A=10 multiplet. We report on a careful measurement of the γ-ray intensities from states populated in the 10B(p,p) reaction at 10 MeV, including a determination of the key E2 branch from the J=2 T=1 state at 5164keV to the J=0 T=1 state at 1740keV of 0.16(4)%. © 2012 American Physical Society.

To study how collective nuclear structure evolves towards mid-shell and test next-generation LaBr3 (Ce) scintillation detectors, measurements of the lifetimes of 21 + states in 168 Hf and 174 W were conducted at the Wright Nuclear Structure Laboratory. Preliminary results indicate that the excellent time and energy resolution of LaBr3 detectors make them well suited to fast timing measurements, allowing for improved background subtraction and peak resolution in comparison to BaF2 detectors. Preliminary analysis shows an order of magnitude reduction in the statistical error of the 2+ lifetimes in comparison to literature values for both nuclei. In the case of 174 W, a substantial reduction of the observed lifetime hints at the possibility of new physics in the region.

Background: The evolution of and interplay between single-particle and collective excitations in the 40 $\ensuremath{\leqslant}N\ensuremath{\leqslant}$ 50 range for ${}_{38}$Sr and ${}_{40}$Zr isotopes have been studied.Purpose: Measurement of the $g$ factor of the 2${}_{1}^{+}$ and 4${}_{1}^{+}$ states in radioactive ${}^{88}$Zr while simultaneously remeasuring the $g({2}_{1}^{+})$ factors in the Sr isotopes and extention of the measurements to higher energy states in the Sr isotopes. Lifetimes of states in these nuclei are determined.Methods: The transient field technique in inverse kinematics and line-shape analysis using the Doppler-shift attenuation method are applied. The ${}^{88}$Zr nuclei were produced by the transfer of an $\ensuremath{\alpha}$ particle from the ${}^{12}$C nuclei of the target to ${}^{84}$Sr nuclei in the beam. The excited states in the stable ${}^{84}$Sr isotopes were simultaneously populated via Coulomb excitation by ${}^{12}$C in the same target. Coulomb excitation measurements on ${}^{86,88}$Sr were carried out with the same apparatus.Results: The resulting $g$ factors and $B(E2)$ values of these nuclei reveal similarities between the two chains of Zr and Sr isotopes. Large-scale shell-model calculations were performed within the ${p}_{3/2},{f}_{5/2},{p}_{1/2},{g}_{9/2}$ orbital space for both protons and neutrons and yielded results in agreement with the experimental data.Conclusions: In this paper the magnetic moments and lifetimes of several low-lying states in ${}^{88}$Zr and ${}^{84.86,88}$Sr have been measured and compared to large-scale shell-model calculations.

Background: The experimental study of $g(Ig2)$ factors of nuclear states can provide information about the evolution of collectivity in certain regions of the nuclear chart, and assist in obtaining a microscopic description of the nuclear wave functions. The measurements and explanations of $g(Ig2)$ factors are still a challenge for experiments and theory.Purpose: Measurement of the $g({2}_{1}^{+})$ and $g({4}_{1}^{+})$ factors, the latter for the first time, in the ${\phantom{\rule{0.16em}{0ex}}}_{44}^{96}$Ru nucleus. Comparison of the experimental results with calculations using the shell model and collective models.Methods: The experiments made use of the transient field technique, using a Coulomb-excitation reaction in inverse kinematics. Large scale shell model calculations were performed; comparisons with previous theoretical predictions, using the tidal-wave model and the hydrodynamical model, were carried out.Results: The values of $g({2}_{1}^{+})=+0.46(2)$ and $g({4}_{1}^{+})=+0.58(8)$ were experimentally obtained. While the $g({2}_{1}^{+})$ value agrees with the hydrodynamical model prediction of $g=Z/A=+0.46$, the $g({4}_{1}^{+})$ is in agreement with the shell model predictions. The trend of the experimental $g$ factors, as a function of nuclear spin, is not reproduced by the theoretical models discussed.Conclusions: Measurements of $g({2}_{1}^{+})$ and $g({4}_{1}^{+})$ in ${}^{96}$Ru were performed. Further theoretical efforts are necessary to explain the trend of the $g$ factors as a function of nuclear spin for the ${}^{96}$Ru nucleus. Future measurements of $g({4}_{1}^{+})$ should reduce the uncertainty of the result.

The low-lying electric dipole ($E1$) strength in the semimagic nucleus ${}^{136}$Xe has been measured, which finalizes the systematic survey to investigate the so-called pygmy dipole resonance (PDR) in all stable even $N=82$ isotones with the method of nuclear resonance fluorescence using real photons in the entrance channel. In all cases, a fragmented resonance-like structure of $E1$ strength is observed in the energy region 5--8 MeV. An analysis of the fragmentation of the strength reveals that the degree of fragmentation decreases toward the proton-deficient isotones, while the total integrated strength increases, indicating a dependence of the total strength on the neutron-to-proton ratio. The experimental results are compared to microscopic calculations within the quasiparticle phonon model. The calculation includes complex configurations of up to three phonons and is able to reproduce also the fragmentation of the $E1$ strength, which allows us to draw conclusions on the damping of the PDR. Calculations and experimental data are in good agreement on the degree of fragmentation and also on the integrated strength if the sensitivity limit of the experiments is taken into account.

The low-spin excitations of the nucleus 146Sm which is just two neutrons and two protons away from the N = 82 shell and Z = 64 subshell closures have been investigated by means of the 143Nd (α, n) and 144Nd (α, 2n) fusion-evaporation reactions. We established 47 hitherto unknown energy levels up to 4.7MeV and 75 new transitions. In addition, 7 spin assignments were possible from the γ-γ angular correlation analysis. The structure of the possible candidates for a 2+ ⊗ 3− quadrupole-octupole multiplet are first discussed in terms of the harmonic vibrational model. A comparison of these states with the corresponding ones in the neighboring N = 84 isotones is also presented. Finally, the structure of the 146Sm nucleus is interpreted in terms of the IBA-spdf model. It is shown that the model is able to reproduce the experimental relative transition strengths of the 2+ ⊗ 3− quadrupole-octupole multiplet and also a series of collective properties such as the proposed double-octupole excitations.

Octupole vibrational states were studied in the nucleus (150)Nd via inelastic proton scattering with 10.9-MeV protons, which are an excellent probe to excite natural parity states. For the first time in (150)Nd, both the scattered protons and the gamma rays were detected in coincidence, giving the possibility to measure branching ratios in detail. Using the coincidence technique, the B(E1) ratios of the decaying transitions for 10 octupole vibrational states and other negative-parity states to the yrast band were determined and compared to the Alaga rule. The positive and negative-parity states revealed by this experiment are compared with interacting boson approximation calculations performed in the spdf boson space. The calculations are found to be in good agreement with the experimental data, for both positive and negative-parity states.

The reaction ${}^{141}$Pr($\ensuremath{\alpha},\phantom{\rule{-0.16em}{0ex}}n$)${}^{144}$Pm was investigated between ${E}_{\ensuremath{\alpha}}=$ 11 MeV and 15 MeV with the activation method using the $\ensuremath{\gamma}\ensuremath{\gamma}$ coincidence method with a segmented clover-type high-purity Germanium (HPGe) detector. Measurements with four other HPGe detectors were additionally made. The comparison proves that the $\ensuremath{\gamma}\ensuremath{\gamma}$ coincidence method is an excellent tool to investigate cross sections down to the microbarn range. The ($\ensuremath{\alpha},\phantom{\rule{-0.16em}{0ex}}n$) reaction at low energy is especially suited to test $\ensuremath{\alpha}+\text{nucleus}$ optical-model potentials for application in the astrophysical $p$ process. The experimentally determined cross sections were compared to Hauser-Feshbach statistical model calculations using different optical potentials and generally an unsatisfactory reproduction of the data was found. A local potential was constructed to improve the description of the data. The consequences of applying the same potential to calculate astrophysical ($\ensuremath{\gamma},\ensuremath{\alpha}$) rates for ${}^{145}$Pm and ${}^{148}$Gd were explored. In summary, the data and further results underline the problems in global predictions of $\ensuremath{\alpha}+\text{nucleus}$ optical potentials at astrophysically relevant energies.

We performed a proton‐capture reaction on 92Mo at energies relevant for the p process. The reaction was investigated by the in‐beam technique using the γ‐ray detector array HORUS (High efficient Observatory for γ‐Ray Unique Sectroscopy) at the TANDEM ion accelerator of the University of Cologne.

For the modeling of the astrophysical s-process the knowledge of neutron capture cross sections is crucial. Where experimental data is not available for the (n,γ) cross-section like e.g. short-lived branching points, the observation of the inverse (γ ,n) reaction can provide useful information – in particular, if the cross section can be measured as a function of energy. The NEPTUN tagger setup at the S-DALINAC delivers a suited tagged photon beam (6–20MeV). In a first test run the resolution turned out to be 35 keV which is close to NEPTUN’s design specifications.

Parity quantum numbers of $J=1$ states up to 7 MeV in the region of the Pygmy Dipole Resonance in $^{140}\mathrm{Ce}$ were determined model independently by combining the methods of Nuclear Resonance Fluorescence and Compton polarimetry. For the first time the well-established method of Compton polarimetry was applied at such high energies. The experiment was performed using a fourfold segmented HPGe clover detector for the detection of the scattered photons. For all investigated dipole transitions asymmetries are found which correspond to negative parity of the excited states.

Mixed-symmetry states of octupole (L = 3) and hexadecapole (L = 4) character have been recently proposed in the N = 52 isotones Zr-92 and Mo-94, based on strong M1 transitions to the lowest-lying 3(-) and 4(+) states, respectively. In order to investigate similar excitations in the heaviest stable N = 52 isotone Ru-96, two inelastic proton-scattering experiments have been performed at the Wright Nuclear Structure Laboratory (WNSL), Yale University, USA and the Institute for Nuclear Physics, University of Cologne, Germany. From the combined data of both experiments, absolute E-1, M-1, and E2 transition strengths were extracted, allowing for the identification of candidates for MS octupole and hexadecapole states. The structure of the low-lying 4(+) states is investigated by means of sdg-IBM-2 calculations.

We have recently performed an experiment for the (p, γ) and (a, γ) reactions on the nucleus 92Mo at energies of relevance for the astrophysical p process. The reactions were investigated by the in-beam technique using the γ-ray detector array HORUS at the ion TANDEM accelerator of the University of Cologne. The experimental results are compared to data stemming from activation measurements and to statistical-model calculations.

Photodissociation reactions play an important role in p-process nucleosynthesis. A precise knowledge of the energy dependence of a cross section is mandatory to determine the reaction rates for astrophysical network calculations. The NEPTUN tagger setup constructed at the S-DALINAC will provide high resolution measurements of (γ,n), (γ,p) and (γ, α) reactions. Besides a general overview on this setup its data acquisition system will be explained in more detail.

An experiment was performed using the FRS-LAND setup at GSI to study the dipole strength distributions above neutron separation threshold for neutron-rich Ni isotopes. Measurements, using the same experimental setup, were also carried out to extract single particle occupancies via knockout reactions to investigate the structure and magicity of the neutron-rich Ni isotopes. The status of the data analysis and preliminary results are presented.