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Clinical risk factors explain only a fraction of the variability of estimated glomerular filtration rate (eGFR) decline in people with type 2 diabetes. Cross-omics technologies by virtue of a wide spectrum screening of plasma samples have the potential to identify biomarkers for the refinement of prognosis in addition to clinical variables. Here we utilized proteomics, metabolomics and lipidomics panel assay measurements in baseline plasma samples from the multinational PROVALID study (PROspective cohort study in patients with type 2 diabetes mellitus for VALIDation of biomarkers) of patients with incident or early chronic kidney disease (median follow-up 35 months, median baseline eGFR 84 mL/min/1.73 m(2), urine albumin-to-creatinine ratio 8.1 mg/g). In an accelerated case-control study, 258 individuals with a stable eGFR course (median eGFR change 0.1 mL/min/year) were compared to 223 individuals with a rapid eGFR decline (median eGFR decline -6.75 mL/min/year) using Bayesian multivariable logistic regression models to assess the discrimination of eGFR trajectories. The analysis included 402 candidate predictors and showed two protein markers (KIM-1, NTproBNP) to be relevant predictors of the eGFR trajectory with baseline eGFR being an important clinical covariate. The inclusion of metabolomic and lipidomic platforms did not improve discrimination substantially. Predictions using all available variables were statistically indistinguishable from predictions using only KIM-1 and baseline eGFR (area under the receiver operating characteristic curve 0.63). Thus, the discrimination of eGFR trajectories in patients with incident or early diabetic kidney disease and maintained baseline eGFR was modest and the protein marker KIM-1 was the most important predictor.

The performance of the novel HPGe-Cluster array DEGAS to be used at FAIR has been studied through GEANT4 simulations using accurate geometries of most of the detector components. The simulation framework has been tested by comparing experimental data of various detector setups. The study showed that the DEGAS system could provide a clear improvement of the photo-peak efficiency compared to the previous RISING array. In addition, the active BGO Back-catcher could greatly enhance the background suppression capability. The add-back analysis revealed that even at a γ multiplicity of six the sensitivity is improved by adding back the energy depositions of the neighboring Ge crystals.

Physics letters / B 820, 136591 (2021). doi:10.1016/j.physletb.2021.136591, Published by North-Holland Publ., Amsterdam

A device to characterize position-sensitive germanium detectors has been implemented at GSI. The main component of this so called scanning table is a gamma camera that is capable of producing online 2D images of the scanned detector by means of a PET technique. To calibrate the gamma camera Compton imaging is employed. The 2D data can be processed further offline to obtain depth information. Of main interest is the response of the scanned detector in terms of the digitized pulse shapes from the preamplifier. This is an important input for pulse-shape analysis algorithms as they are in use for gamma tracking arrays in gamma spectroscopy. To validate the scanning table, a comparison of its results with a second scanning table implemented at the IPHC Strasbourg is envisaged. For this purpose a pixelated germanium detector has been scanned.

Monte Carlo simulations of one of the possible configurations of the imaging phase for the DEGAS spectrometer situated at the DESPEC/NUSTAR experiment have been performed. The geometry consists of the coupling of the high-resolution γ spectroscopy array, AGATA, with a high-resolution segmented planar detector utilized as an implantation detector in a compact configuration. The sensitivity and performance of the array in terms of efficiency and imaging capability is deduced.

Products of the fusion-evaporation reaction 48Ca + 243Am were studied with the TASISpec set-up at the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. Amongst the detected thirty correlated α-decay chains associated with the production of element Z=115, two recoil-α-fission and five recoil-α-α-fission events were observed. The latter five chains are similar to four such events reported from experiments performed at the Dubna gas-filled separator, and three such events reported from an experiment at the Berkeley gas-filled separator. The four chains observed at the Dubna gas-filled separator were assigned to start from the 2n-evaporation channel 289115 due to the fact that these recoil-α-α-fission events were observed only at low excitation energies. Contrary to this interpretation, we suggest that some of these recoil-α-α-fission decay chains, as well as some of the recoil-α-α-fission and recoil-α-fission decay chains reported from Berkeley and in this article, start from the 3n-evaporation channel 288115.

A reliable and simple-to-use algorithm was developed for the energy-calibration of double-sided silicon strip detectors (DSSSDs). It works by enforcing mutual consistency of p-side and n-side information for every detected event. The procedure does not rely on a dedicated data set for calibration and is robust enough to work fully automated without human supervision. The method was developed and applied to data from a DSSSD of the Lund-York-Cologne CAlorimeter (LYCCA) for the HISPEC experiment at FAIR. It has been tested on ions in the A â 90 mass range at energies of E kin â 300 MeV / u .

Summary Ectopic lipid deposition and altered mitochondrial dynamics contribute to the development of obesity and insulin resistance. However, the mechanistic link between these processes remained unclear. Here we demonstrate that the C16:0 sphingolipid synthesizing ceramide synthases, CerS5 and CerS6, affect distinct sphingolipid pools and that abrogation of CerS6 but not of CerS5 protects from obesity and insulin resistance. We identify proteins that specifically interact with C16:0 sphingolipids derived from CerS5 or CerS6. Here, only CerS6-derived C16:0 sphingolipids bind the mitochondrial fission factor (Mff). CerS6 and Mff deficiency protect from fatty acid-induced mitochondrial fragmentation in vitro, and the two proteins genetically interact in vivo in obesity-induced mitochondrial fragmentation and development of insulin resistance. Our experiments reveal an unprecedented specificity of sphingolipid signaling depending on specific synthesizing enzymes, provide a mechanistic link between hepatic lipid deposition and mitochondrial fragmentation in obesity, and define the CerS6-derived sphingolipid/Mff interaction as a therapeutic target for metabolic diseases.

Familial hyperlipidemias including but not limited to familial hypercholesterolemia (FH) are often evaluated distinctly from population-based hyperlipidemias. We asked whether this practice is warranted either by greater coronary artery disease (CAD) risk or by different detailed lipid profiles in

The Super-FRS in-flight fragment separator at FAIR will be used to produce exotic nuclei at relativistic energies. High resolution experiments in ion traps with the separated fragments will be performed after they are slowed-down in matter and quickly extracted from a gas-filled stopping cell. Such experiments require an effective range bunching with a high-resolution magnetic spectrometer in combination with a wedge-shaped degrader at the dispersive focal plane. The ion-optical system of the spectrometer proposed here is rather versatile because it consists of several dipole and quadrupole magnets arranged such to serve as an energy-buncher and also as a large-acceptance spectrometer for the analysis of secondary reaction products. The performance and the experimental potential of such a multi-purpose spectrometer are described.

The imaging scanning technique for the characterisation of large volume, highly segmented, HPGe detectors is demonstrated by comparing the measured spatial response of a symmetric AGATA crystal versus the theoretical calculations obtained with the Multi-Geometry Simulation (MGS) code. The signal rise-times measured as a function of the gamma-ray interaction positions, in both coaxial and planar regions of the detection volume, are presented and confronted with the expected behaviour obtained via MGS. The transition in charge carrier transport behaviour as a function of the depth is studied for the region of the complex electric field. In general, a fairly good agreement between theory and experiment is obtained. Only systematic deviations between simulation and measurement are observed in the critical front part of the AGATA detector. They may be ascribed to a non-linear impurity concentration profile of the germanium crystal.

The main objective of the Advanced GAmma Tracking Array (AGATA) is the investigation of the structure of exotic nuclei at the new generation of RIB facilities. As part of the preparatory phase for FAIR-NUSTAR, AGATA is going to be installed at the FRS fragmentation facility of the GSI centre for an experimental campaign to be performed in 2012 and 2013. Owing to its γ - ray tracking capabilities and the envisaged enhancement in resolving power, a series of in-flight γ - ray spectroscopy experiments are being planned. The present work describes the conceptual design of this first implementation of AGATA at GSI-FRS, and provides information about the expected performance figures. According to the characteristics of each particular experiment, it is foreseen that the target–array distance is adjusted in order to achieve the optimum compromise between detection efficiency and energy resolution, or to cover an specific angular range of the emitted electromagnetic radiation. Thus, a comprehensive Monte Carlo study of the detection sensitivity in terms of photopeak efficiency, resolution and peak-to-total ratio, as a function of the target–array distance is presented. Several configurations have been investigated, and MC-calculations indicate that a remarkable enhancement in resolving power can be achieved when double-cluster AGATA detectors are developed and implemented. Several experimental effects are also investigated. This concerns the impact of passive materials between the target and the array, the angular distribution of the detection efficiency and the influence of target thickness effects and transition lifetimes in the attainable detection sensitivity. A short overview on half-life measurements via lineshape effects utilizing AGATA is also presented.

With a new detector setup and the high-resolution performance of the fragment separator FRS at GSI we discovered 57 new isotopes in the atomic number range of 60$\leq Z \leq 78$: \nuc{159-161}{Nb}, \nuc{160-163}{Pm}, \nuc{163-166}Sm, \nuc{167-168}{Eu}, \nuc{167-171}{Gd}, \nuc{169-171}{Tb}, \nuc{171-174}{Dy}, \nuc{173-176}{Ho}, \nuc{176-178}{Er}, \nuc{178-181}{Tm}, \nuc{183-185}{Yb}, \nuc{187-188}{Lu}, \nuc{191}{Hf}, \nuc{193-194}{Ta}, \nuc{196-197}{W}, \nuc{199-200}{Re}, \nuc{201-203}{Os}, \nuc{204-205}{Ir} and \nuc{206-209}{Pt}. The new isotopes have been unambiguously identified in reactions with a $^{238}$U beam impinging on a Be target at 1 GeV/u. The isotopic production cross-section for the new isotopes have been measured and compared with predictions of different model calculations. In general, the ABRABLA and COFRA models agree better than a factor of two with the new data, whereas the semiempirical EPAX model deviates much more. Projectile fragmentation is the dominant reaction creating the new isotopes, whereas fission contributes significantly only up to about the element holmium., 9 pages, 4 figures

Masses of 238U projectile fragments have been measured with time-resolved Schottky Mass Spectrometry (SMS) at the FRS-ESR facility at GSI. The exotic nuclei were created in the production target at the entrance of the fragment separator FRS, spatially separated in flight and injected into the storage-cooler ring ESR at about 70% light velocity. This means the ions were mainly bare or carried only a few electrons, e.g., the population of Li-like ions was below 1% for Pt fragments. Accurate newmass values of 33 neutron-rich, stored exotic nuclei in the element range from platinum to uranium have been obtained for the first time. In total more than 150 nuclides including references with well-known masses have been covered in this large-area SMS measurement. A novel data analysis has been applied which reduces the systematic errors by taking into account the velocity profile of the cooler electrons and the residual ion-optical dispersion in this part of the storage ring. The experiment, the data analysis, and the mass values are presented. The experimental data are compared with theoretical predictions demonstrating systematic deviations of up to 1500 keV from modern mass models.

The design, R&D, and testing of a new plastic-scintillator detector for Time-of-Flight measurements with relativistic heavy-ion beams are presented. A design approach using 32 independent precise timing measurements of the same physical event is followed. This is different from the conventional scheme, which aims at two or four high-precision measurements. A circular, 27 cm in diameter, BC-420 plastic-scintillator sheet is read-out by 32 photomultiplier tubes in order to achieve an intrinsic detector resolution on the order of 10 ps root mean square.

In this work, a novel imaging technique for the spatial calibration of a gamma camera is presented. The latter is aimed for the characterisation of the charge signals of 3D-position sensitive HPGe detectors. The characterisation method itself is based on pulse shape comparison (PSC) technique. The performance of the device is improved by implementing a gamma camera or position sensitive detector (PSD). This PSD consists of a uniform LYSO scintillating crystal optically glued to a crossed-wire position sensitive photomultiplier tube (PSPMT) from Hamamatsu. The individual multianode readout (IMAR) approach is used to improve its spatial resolution and to enlarge its field of view. A Compton scattering imaging technique is implemented to perform an accurate position calibration of the gamma camera.

A new technique for the pulse-shape characterization of γ ‐ ray position sensitive germanium detectors is presented. This method combines the pulse shape comparison scan (PSCS) principle with a γ ‐ ray imaging technique. The latter is provided by a supplementary, high performance, position sensitive γ ‐ ray scintillator detector. We describe the basic aspects of the method and we show measurements made for the study of pulse-shapes in a non-segmented planar HPGe detector. A preliminary application of the PSCS is carried out, although a more detailed investigation is being performed with highly segmented position sensitive detectors.

For spectroscopy, polarimetry and imaging purposes a new gamma-ray tracking algorithm has been developed featuring identification of Compton escape events. The rejection of these events results in ...

238U projectile fragments have been created at the entrance of the fragment separator FRS, spatially separated in flight within 0.45 μs and injected into the storage-cooler ring ESR at 7.9 Tm corresponding to about 70% light velocity. Accurate new mass values and lifetime information of the stored exotic nuclei in the element range from platinum to uranium have been obtained with single-particle Schottky spectrometry. In this experiment the new isotopes of 236Ac, 224At, 221Po, 222Po, and 213Tl were discovered. The isotopes were unambiguously identified and their masses measured. In addition, the time-correlated data have provided information on the lifetime of the new nuclides. The discovery of isotopes along with accurate mass measurement has been achieved for the first time at the FRS-ESR facility. The results will contribute to the knowledge of the decay products from the r-process nuclei and enable a crucial test of the predictive power of modern nuclear mass and half-life models.

The lineshapes and peak position of Doppler corrected γ -ray spectra from in-beam experiments at relativistic energies are investigated with respect to the intrinsic energy resolution of the employed detectors, the particles’ velocities, and the photons’ emission angle uncertainties at the moment of γ -ray emission. The uncertainties in velocity and photon emission angle are dependent on the lifetime of the excited state. The impact of these two observables on the lineshape and energy resolution are studied for the RISING γ -spectrometer by means of simulations and experimental results from a two-step fragmentation experiment at ≈ 200 MeV / u . Potential use of the distinct lineshape for lifetime determination is demonstrated for measured γ -ray transitions.

A Monte-Carlo simulation package has been developed to model the response of a detector system for ion identification used in conjunction with ion separators following nuclear reactions. The simulation is written predominantly using the GEANT4 framework but utilises the ion transport code MOCADI for accurate separator and reaction modelling. A novel MOCADI–GEANT4 interface has been developed to utilise the parameter file output option of MOCADI as an event generator for the GEANT4 detector simulation. Test simulation results have been compared with experimental data and excellent agreement was observed. The simulation has successfully been used to model a new particle detection system prototype (Lund-York-Cologne CAlorimeter (LYCCA)-0) and validate a method of ion identification using energy and time-of-flight with this system.

Cell membranes predominantly consist of lamellar lipid bilayers. When studied in vitro, however, many membrane lipids can exhibit non-lamellar morphologies, often with cubic symmetries. An open issue is how lipid polymorphisms influence organelle and cell shape. Here, we used controlled dimerization of artificial membrane proteins in mammalian tissue culture cells to induce an expansion of the endoplasmic reticulum (ER) with cubic symmetry. Although this observation emphasizes ER architectural plasticity, we found that the changed ER membrane became sequestered into large autophagic vacuoles, positive for the autophagy protein LC3. Autophagy may be targeting irregular membrane shapes and/or aggregated protein. We suggest that membrane morphology can be controlled in cells.

The neutron-rich N = 126 nucleus Au-205 has been populated following the relativistic energy projectile fragmentation of E/A = 1 GeV Pb-208, and studied via charged-particle decay spectroscopy. An internal decay with a transition energy of 907(5) keV and a half-life of T-1/2 = 6(2) s has been identified through the observation of the corresponding K and L internal conversion electron lines. The 907 keV energy level corresponds to the pi h(11/2)(-1) proton-hole state and decays both internally into the pi d(3/2)(-1) ground-state and via beta decay into Hg-205. The obtained data provides information on the evolution of single-proton hole energies which are vital inputs of shell model descriptions for nuclei around the Pb-208(82)126 doubly magic core. (C) 2009 Elsevier B.V. All rights reserved.

An active stopper for the RISING project at GSI has been developed for beta-decay studies and conversion electron spectroscopy following projectile fragmentation/fission reactions. This system employs six double-sided silicon strip detectors in the final focal plane of the GSI FRagment Separator (FRS) to detect both the fragment implantations and their subsequent charged-particle (alpha, beta, p) decays. The wide range of energy response required (150keV up to several GeVs) was covered by the use of a logarithmic preamplifier. Measurements with a Bi-207 conversion electron source yielded an energy resolution of 20 keV at electron energies of similar to 1 MeV and a detection threshold of 150 keV. The response to the implantation of 400 AMeV Xe-136 ions in the active stopper is also discussed in the present paper. (c) 2008 Elsevier B.V. All rights reserved., This work is supported by EPRSC (UK) and EURONS (EU Contract number 506065). Work partially supported by Spanish MEC, Grants FPA2005-03993 and FPA2005-00732. A.A. recognizes partial support of the Ramon y Cajal program.

The first 2+ states in 134Ce and 136Nd and the second 2+ state in 136Nd were populated by Coulomb excitation at relativistic energies, and γ-rays were measured using the RISING setup at GSI. For 134Ce an indication of the excitation to the second 2+ state was observed. This experiment performed for the first time Coulomb excitation to second 2+ states with rare isotope beams at relativistic energies. For 136Nd the B ( E 2 ; 2 1 + → 0 + ) , B ( E 2 ; 2 2 + → 0 + ) , and B ( E 2 ; 2 2 + → 2 1 + ) values relative to the previously known B ( E 2 ; 2 1 + → 0 + ) value for 134Ce are determined as 81(10), 11(3) and 180(92) W.u., respectively. The results are discussed in the framework of geometrical models that indicate pronounced γ-softness in these nuclei.

A compilation of the available experimental internal conversion coefficients (ICCs), αT, αK, αL, and ratios K/L and K/LM of high multipole (L > 2) transitions for a number of elements in the range 21 ⩽ Z ⩽ 94 is presented. Our listing of experimental data includes 194 data sets on 110 E3 transitions, 10 data sets on 6 E4 transitions, 11 data sets on 7 E5 transitions, 38 data sets on 21 M3 transitions, and 132 data sets on 68 M4 transitions. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer [R.S. Hager, E.C. Seltzer, Nucl. Data Tables A 4 (1968) 1], Rosel et al. [F. Rosel, H.M. Fries, K. Alder, H.C. Pauli, At. Data Nucl. Data Tables 21 (1978) 91], and BRICC. The relative percentage deviations (%Δ) have been calculated for each of the above theories and the averages ( % Δ ¯ ) are estimated. The Band et al. [I.M. Band, M.B. Trzhaskovskaya, C.W. Nestor Jr., P.O. Tikkanen, S. Raman, At. Data Nucl. Data Tables 81 (2002) 1] tables, using the BRICC interpolation code, are seen to give theoretical ICCs closest to experimental values.

For DEcay SPECtroscopy (DESPEC) experiments with implanted radioactive beams a high resolution gamma tracking array is being designed at GSI. Exploiting the imaging capability of the array, a background suppression method is developed based on a separation of events originating from the target and from localized background sources. Monte-Carlo simulations show that the suppression of the background by a factor from 10 up to 100 or even more can be achieved. The Peak/Total ratio can be as well significantly increased. The dependence of the suppression efficiency on the detector properties is discussed.

The preliminary results from the RISING Stopped Beam Isomer Campaign are presented, with specific focus on results of the initial experiment to investigate isomeric decays along the N=Z line around A similar to 80-90 following the projectile fragmentation of a Ag-107 primary beam at an energy of 750 MeV per nucleon. A description of the technical aspects behind the design of the RISING array is presented, together with evidence for previously unreported isomeric decays in Tc-87,Tc-88 and the N=Z nuclei Nb-82(41) and Tc-86(43).

The first excited 2+2+ state of 36Ca has been identified by its γ -decay, exploiting the two-step fragmentation technique at the FRS-RISING setup at GSI. This is the heaviest Tz=−2Tz=−2 nucleus in the Segré chart in which a γ-decay of an excited state has been observed. A stable beam of 40Ca at View the MathML source420AMeV impinged on a primary 9Be target. Out of the secondary beam of fragmentation products, 37Ca was separated by the FRS and struck on a second 9Be target at the final focus of the FRS. The energy for the View the MathML source21+ decay of 36Ca was determined to be 3015(16) keV, which is 276 keV lower than in its T=2T=2 mirror 36S. This mirror energy difference (MED) is discussed in the framework of shell model calculations using a 16O core, the sd shell isospin symmetric interaction USD and experimental single-particle energies from 17O and 17F. The results show that the MED within the sd shell provide a sensitive test for the evolution of the N , Z=14,16Z=14,16 subshell gaps towards the driplines. Especially the N , Z=16Z=16 gap is determined by Thomas–Ehrman shift in the A=17A=17, T=1/2T=1/2 isospin doublet, while Coulomb effects are found to have marginal influence. ispartof: Physics Letters B vol:647 issue:4 pages:237-242 status: published

A novel Calorimeter Telescope (CATE) is employed in the fast beam Rare Isotope Investigations at GSI (RISING) g-campaign with relativistic energies at the Fragment Separator (FRS) at GSI. CATE consists of nine modular Si2CsIðTlÞ detector telescopes for position

The population of metastable states produced in relativistic-energy fragmentation of a U-238 beam has been measured. For states with angular momentum greater than or similar to 20h, a much higher population than expected has been observed. By introducing a collective component to the generation of angular momentum the experimental data can be understood. This is the first time that a collective degree of freedom has be shown to play a major role in such high-energy collisions. (c) 2005 Elsevier B.V. All rights reserved.

The first excited 2 + states in 54,56,58Cr were populated by Coulomb excitation at relativistic energies and γ rays were measured using the RISING setup at GSI. For 56Cr and 58Cr the B ( E2 , 2 1 + → 0 + ) values relative to the previously known B ( E 2 ) value for 54Cr are determined as 8.7(3.0) and 14.8(4.2) W.u., respectively. The results are consistent with a subshell closure at neutron number N = 32 which was already indicated by the higher energy of the 2 1 + state in 56Cr. Recent large-scale shell model calculations using effective interactions reproduce the trend in the excitation energies, but fail to account for the minimum in the B ( E 2 ) values at N = 32 .

Novel γ ray imaging methods relying on the Compton effect are described. Ge tracking detectors, e.g. of AGATA-type, employing two-dimensional segmentation, pulse shape analysis and tracking of Compton scattered γ rays show omni-directional position sensitivity. The obtainable angular resolution paired with the high energy resolution of Ge allows precise location of specific target isotopes over some ten to hundred meters in the presence of strong natural background radiation. At shorter distances the method is orders of magnitude more sensitive than conventional collimator-based imaging. Another basic method uses directional information from a point-like positron source placed in front of an object to be examined. A position detector behind the source measures 511 keV γ rays from positron annihilation to determine the direction of the correlated 511 keV γ rays used to probe the object. Detecting the probing γ ray after Compton scattering off the object in time coincidence to the position determining γ ray enables to map the matter distribution in the object. Among other applications the method can be employed for the detection of land mines.

The Rare ISotopes INvestigation at GSI project combines the former EUROBALL Ge-Cluster detectors, the MINIBALL Ge detectors, BaF2--HECTOR detectors, and the fragment separator at GSI for high-resolution in-beam gamma-ray spectroscopy measurements with radioactive beams. These secondary beams produced at relativistic energies are used for Coulomb excitation or secondary fragmentation experiments in order to explore the nuclear structure of the projectiles or projectile like nuclei by measuring de-excitation photons. The newly designed detector array is described and the performance characteristics are given. Moreover, particularities of the experimental technique are discussed.

4 pages, 4 figures.-- Printed version published Dec 27, 2004.-- Issue title: "Proceedings of the Sixth International Conference on Radioactive Nuclear Beams (RNB6)" (Argonne, Illinois, US, Sep 22-26, 2003)., One-nucleon removal reactions at relativistic energies have been used as a spectroscopic tool to characterise the ground state properties of several neutron-rich isotopes in the sd-shell. Using the FRS at GSI, the longitudinal momentum distributions of the emerging fragments after one-nucleon removal were measured. The relative contributions of the remaining fragments in their ground and excited states have been determined from measurements of γ rays in coincidence with the longitudinal momentum distributions. In particular the breakup of O-23 has been investigated. The interpretation of our measurements, in the framework of a simple theoretical model, favours a spin and parity assignment of 1/2+ for the O-23 ground state in agreement with shell model predictions.

A γ-ray imaging method is described which is suitable for non-destructive and non-invasive determination of amount and distribution of matter in objects. A point-like positron source is placed in front of the object to be examined. A position detector behind the source measuring 511 keV γ-rays from positron annihilation determines the direction of the correlated 511 keV γ-rays used to probe the object. Detecting the probing γ-ray after transmission through or scattering off the object in time coincidence to the position determining γ-ray enables to map the thickness and density distribution of the object. The method and system can be employed for security inspection of concealed items, control of erosion, deposition and structural defects, and the detection of land mines.

The structure of heavy nuclei has been investigated in GSI by means of γ-ray isomer spectroscopy following projectile fragmentation. The obtained results as well as experimental aspects relevant for further studies are discussed.

One-proton removal reactions of 936 MeV/u 8 B have been studied with carbon and lead as breakup targets. Using the FRS at GSI, the longitudinal momentum distributions of the 7 Be fragments and the one-proton removal cross section of 8 B were measured. The relative contributions of the breakup channels leading to 7 Be in its ground state and excited state at 429 keV ( 7 Be ∗ ) have been determined from measurements of γ rays in coincidence with the fragments from the one-proton removal reaction. The experimental breakup data are discussed in the context of a theoretical ( α+ 3 He + p ) three-body model. The combined data from the two targets allow a determination of the weight of the 7 Be ∗ component in the 8 B ground state wave function as (13.3±2.2%)

The new ΔE/E detection system, calorimeter telescope (CATE), for charge and mass determination of heavy ions at high energies (⩾100 MeV/n) has been designed. CATE, a calorimeter telescope will consist of position sensitive Si detectors for ΔE determination and scintillators, readout by either PIN diode or PMT, for total-E determination. Different scintillation detectors were tested with 130Sn, 186Pb, 197Au and 238U beams of (100–300) MeV/n ion energy. By properly selecting the beam species from the FRS and applying position corrections, an energy resolution of ≃0.5% FWHM was observed. The corresponding mass resolution of 1/200 is adequate for employment of CATE in the Fast Beam RISING campaign at GSI.

MINIBALL a highly efficient, position sensitive γ -spectrometer is under construction for upcoming radioactive-beam experiments. In contrast to high spin arrays the total full energy peak efficiency and not the resolving power is optimized with a factor of two larger efficiency for γ -ray energies up to 10 MeV and for low to medium γ -ray multiplicity events. Cluster detectors, incorporating three or four Ge crystals, will be employed to provide high flexibility and to accomodate the various demands of the experiments.

We present results on the isomer spectroscopy of a number of neutron-rich rare earth and transitional elements with A N 190 200, following the projectile fragmentation of a 1 GeV per nucleon ‘08Pb beam. The technique was sensitive to decays from metastable states with lifetimes in the nanoto millisecond time range. The nuclei of interest were separated and unambiguously identified on an event-by-event basis using the Fragment Separator at GSI. The analysis allows a clear differentiation between ions of different charge states and places a new lower limit of -15 ns, on the lifetimes of isomers which have been studied using this technique.

Two excited J(pi)=0(+) states in Pb-186 populated in the a-decay of Po-190 have been identified through alpha -particle/conversion electron coincidences in an experiment at the velocity filter SHIP ...

Dedicated Ge-detector arrays are being developed for the investigation of rare γ decays with low γ-ray multiplicity at the upcoming radioactive ion beam facilities. These arrays are optimized for the high full-energy peak efficiency and angular resolution of the γ-ray detection needed for a proper Doppler correction of the γ-rays emitted by fast recoiling nuclei. MINIBALL will consist of 40 six-fold segmented, encapsulated Ge detectors which are clustered in eight cryostats with three detectors each and four cryostats with four detectors, respectively. The individual components - the six-fold segmented Ge detector, the cryostats, the fast preamplifier, the digital pulse-processing electronics and the mechanical frame - and their properties are described. The results of test measurements with the first MINIBALL cluster detector using a 137 Cs source and the in-beam reaction D( 37 Cl, n) 38 Ar are presented. It is shown that from pulse-shape analysis of the events within a detector segment the effective granularity of the MINIBALL array can be enhanced from 240 to ∼ 4000. The specifications of MINIBALL are compiled on the basis of experimental data. First results with a 12-fold segmented, encapsulated detector are discussed with respect to the feasibility of future γ-ray tracking arrays.

A 4 pi silicon bail for detection and identification of light charged particles in large multidetector gamma-arrays as EUROBALL is presented. The design is based on a N = 42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive material for gamma-rays is minimized to the detector thickness of 300 or 500 mu m and a 0.63 mm ceramic backing. The geometrical coverage is designed for about 90% of 4 pi. A pulse shape discrimination method with totally depleted detectors working in the reverse mount allows identifying protons and alpha-particles above an energy threshold of about 2 MeV. The performances of the ball were rested at the tandem - booster accelerator combination of the MPI Heidelberg in two experiments using the high-recoil reaction of 228 MeV Ni-58 + Ti-46 and the low-recoil reaction of 95 MeV O-16 + Ni-58. The two-dimensional spectra of zero-crossing (ZC) versus energy confirmed an excellent discrimination of protons and alpha-particles in all the detectors at different angles. The energy spectra of protons and alpha-particles measured in the experiments are presented. too. The gamma-spectra measured in coincidence with various combinations of emitted particles showed a high selectivity of the ball. The reduced total efficiency for protons of 59% and 55% and alpha-particles of 44% and 32% measured in a nuclear spectroscopy application is analyzed in a Monte-Carlo simulation (GEANT). It is due to a combined influence of a thick target needed to stop the recoiling residual nuclei and thick absorbers needed to protect the Si-detectors from scattered beam. The results along with the GEANT extrapolation to optimum experimental conditions confirm that RoSiB is a highly efficient and selective device for identification of rare reaction channels with heavy ions. (C) 2000 Elsevier Science B.V. All rights reserved. (Less)

The sensitivity of gamma-ray spectrometers for nuclear structure studies has improved by two to three orders of magnitude within the last 10 years. This impressive progress is based on larger HPGe crystals, composition of several crystals into a detection unit and electrical segmentation of the detector contacts. Current development projects are concentrating on optimizing the solid angle coverage of detector arrays to further increase the efficiency and on increasing the effective granularity of the detectors. The latter requires further segmentation and gamma-hit position determination by signal-shape analysis.

E0-enhanced spectra of conversion electrons taken after (α,α′) and (α,2n) reactions and after projectile Coulomb excitation improve our knowledge about first and second excited bands in 238 U and 240 Pu built on 0 2 + and 0 3 + states which lie anomalously close together. The two bands are of different structure.