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γ-Ray spectroscopy continues to be an important tool for the study of nuclei. Excitation energies can be measured directly and in model-independent ways, and thus are among the key observables that can guide our understanding of atomic nuclei. With the availability of short-lived rare-isotope beams, the development of position sensitivity of γ-ray detection systems has been crucial in combating the Doppler broadening encountered for the energies of γ-rays emitted in flight, which are necessary to obtain good energy resolution while maintaining high efficiency. The advanced γ-ray tracking array GRETINA began its science mission at the National Superconducting Cyclotron Laboratory (NSCL), where rare-isotope beams are produced at velocities exceeding 30% of the speed of light. With selected examples from nuclear structure physics and nuclear astrophysics, we show the breadth and reach of the science program afforded by GRETINA and provide an outlook for what can be accomplished with the full 4π array GRETA at the Facility for Rare Isotope Beams (FRIB). [ABSTRACT FROM AUTHOR]

Improved precisions of the energies and intensities of the γ rays emitted in the decays of 109 Pd and 111g,m Pd have been obtained based on a high-resolution spectroscopic study of these γ emissions from radioactive samples produced by neutron capture by natural Pd. Correspondingly improved values of the energies and β feedings of the levels in the 109, 111 Ag daughters have been deduced. More precise energies and intensities have also been determined for the γ rays emitted in the decays of the 111 Pd daughter activities 111g,m Ag to 111 Cd. [ABSTRACT FROM AUTHOR]

In this paper a method for lifetime measurements in the sub-picosecond regime via the Doppler-shift attenuation method (DSAM) following the inelastic proton scattering reaction is presented. In a pioneering experiment we extracted the lifetimes of 30 excited low-spin states of 96 Ru, taking advantage of the coincident detection of scattered protons and de-exciting γ-rays as well as the large number of particle and γ-ray detectors provided by the SONIC@HORUS setup at the University of Cologne. The large amount of new experimental data shows that this technique is suited for the measurement of lifetimes of excited low-spin states, especially for isotopes with a low isotopic abundance, where ( n , n ′ γ ) or – in case of investigating dipole excitations – ( γ , γ ′ ) experiments are not feasible due to the lack of sufficient isotopically enriched target material. [ABSTRACT FROM AUTHOR]

A combination of germanium detectors was installed at the PF1B neutron guide of the ILL to perform prompt spectroscopy of neutron-rich nuclei produced in the neutron-capture induced-fission of U and Pu. In addition, LaBr detectors from the FATIMA Collaboration were installed to complement with the EXOGAM clovers to measure lifetimes of low-lying excited states. The measured characteristics and online spectra indicate very good performances of the overall set-up. [ABSTRACT FROM AUTHOR]

High radioactivity in a relatively saline confined aquifer water in different locations of the Disi area (South East of Jordan) was reported by some authors who recommended further investigation on the impact of that water on irrigated soils. Five well water samples (jointly used for irrigation and drinking) and 28 surface and subsurface soil samples from five profiles were collected from that area for the purpose of this study. Selected mineralogical, chemical, and physical properties of the soil samples were determined. Mineralogical compositions of the 28 soil samples were identified using x-ray diffraction, x-ray fluorescence, and ICP-MS techniques. Determination of activity concentrations of 238U, 226Ra and 228Ra in the five well waters and 22 soil samples from 4 sites (including a native soil) were determined using γ-ray spectroscopy. The results showed low salinity levels of both soil and water samples and low clay and organic matter contents in all soil samples. Kaolinite and mica were the dominant clay minerals with Fe substituting Al in the octahedral layer of these minerals. The average activity concentration of 226Ra and 228Ra in the well-water samples were 0.31 ± 0.09 and 1.74 ± 0.12 BqL−1, respectively. Such a high specific activity could be ascribed to the water enrichment with 228Ra diffusing from 232Th-rich sandstone geologic strata. Average concentrations of 238U and 232Th in the soil samples (0–120 cm depth) were 1.48 ± 0.38 mg kg−1 and 4.78 ± 1.55 mg kg−1, respectively. High correlation between these two radionuclides (R2 = 0.90) indicated no specific enhancement of these two metals from external sources, especially through chemical precipitation from irrigation water. Average activity concentration of 238U, 226Ra, and 228Ra in the soil samples were substantially low (20.8 ± 5.6, 16.94 ± 4.48, and 20.7 ± 6.2 Bq kg−1, respectively). No particular changes were observed when comparing concentration or radioactivity of these radionuclides with depth of a given soil or between irrigated and native soil samples at comparable depths. This could lead to the conclusion that there was no appreciable precipitation or adsorption of these radioactive metals from the percolating irrigation water onto the sandy soil complex. [ABSTRACT FROM AUTHOR]

The measurement of cross-sections producing I n 115 m has been carried out within the energy range of 7–20 MeV. The neutron activation analysis (NAA) followed by off-line γ -ray spectrometry have been used for the purpose. The quasi-monoenergetic neutron beam was produced using the L i (p , n) 7 reaction at the 14UD BARC-TIFR Pelletron accelerator facility at Mumbai, India. The ratio technique of covariance analysis has been used to estimate the uncertainty and correlation between the current experimental data which considers the collective uncertainty from all the attributes in the measurement. The measured cross-sections were compared with the experimental data from the previous literatures, different evaluated data libraries such as ENDF/B-VIII.0, JEFF-3.3, JENDL-4.0, CENDL-3.2 and the theoretically predicted results using the TALYS 1.95 and EMPIRE 3.2.3. The experimental results presented in this work are crucial for the measurement of neutron flux in the NAA technique. • Cross-section of I n (n , n ′) 115 m 115 I n reaction has been measured using the standard neutron activation analysis technique. • The measured cross-sections are compared with results of previous literatures and with the evaluated data libraries. • Theoretical calculations have been performed using nuclear modular code TALYS-1.95 and EMPIRE-3.2.3. • A detailed covariance analysis has been used to measure uncertainties in the measured data. [ABSTRACT FROM AUTHOR]

Abstract: The influence on γ-ray spectra of differential nonlinearities (DNL) in subranging, pipelined analog-to-digital converts (ADCs) used for digital γ-ray spectroscopy was investigated. The influence of the DNL error on the γ-ray spectra, depending on the input count-rate and the dynamic range has been investigated systematically. It turned out that the DNL becomes more significant in γ-ray spectra with larger dynamic range of the spectroscopy system. An event-by-event offline correction algorithm was developed and tested extensively. This correction algorithm works especially well for high dynamic ranges. [Copyright &y& Elsevier]

Abstract: A dedicated setup for the in-beam measurement of absolute cross-sections of astrophysically relevant charged-particle induced reactions is presented. These, usually very low, cross-sections at energies of astrophysical interest are important to improve the modeling of the nucleosynthesis processes of heavy nuclei. Particular emphasis is put on the production of the p nuclei during the astrophysical γ process. The recently developed setup utilizes the high-efficiency γ-ray spectrometer HORUS, which is located at the 10MV FN tandem ion accelerator of the Institute for Nuclear Physics in Cologne. The design of this setup will be presented and results of the recently measured 89Y(p,γ)90Zr reaction will be discussed. The excellent agreement with existing data shows that the HORUS spectrometer is a powerful tool to determine total and partial cross-sections using the in-beam method with high-purity germanium detectors. [Copyright &y& Elsevier]

A multidetector gamma array (GDA), for studying nuclear structure was built with ancillary devices namely gamma multiplicity filter and charged particle detector array. This facility was designed for in-beam gamma spectroscopy measurements in fusion evaporation reactions at Inter-University Accelerator Centre, New Delhi. Description of the facility and in-beam performance with two experimental studies done are presented. This array was used in a number of nuclear spectroscopic and reaction investigations. [ABSTRACT FROM AUTHOR]

A general understanding of the molecular plating process was obtained recently, which serves as a first step towards further improvements of the method aiming, for example, at the production of smooth, crack-free targets for nuclear physics applications. Constant current density electrolysis experiments were performed in organic media containing the model electrolyte Nd(NO)·6HO. The process was investigated by considering influences of the electrolyte concentration (0.11, 0.22, 0.44 mM), the surface roughness of the deposition substrates (a few tens of nm), and the plating solvent (an isopropanol/isobutanol mixture, and N, N-dimethylformamide). The response of the process to changes of these parameters was monitored by recording cell potential curves and by characterizing the obtained deposits with γ-ray spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. By changing the solvent from isopropanol/isobutanol mixtures to N, N-dimethylformamide, we have succeeded in producing smooth, crack-free Nd targets. [ABSTRACT FROM AUTHOR]

LaBr 3 :(Ce) exhibits the best energy resolution among scintillation γ-ray detectors. The excellent energy resolution of this detector has made it suitable for many radiation detection applications such as environmental monitoring, medical imaging, nuclear security, nuclear physics experiments, etc. However, LaBr 3 :(Ce) crystal endures from internal radioactivity which produces a considerable background in the measurements. The problem of internal radiation is particularly acute with large size detectors, measuring low-intensity γ-rays. A considerable part of the internal radiation comes from the α-decay of 227Ac and its daughters which are present as an impurity in the detector's crystal. Unfortunately, due to the very similar chemical properties of Actinium and Lanthanum, it is very difficult to remove the 227Ac impurity by using purification processes, and therefore, the α-background is present in all the commercial crystals. A practical approach for the reduction of this problem is to identify the α-events through an electronic analysis of the shape of output pulses of the detector and reject them. In the past, several digital pulse-shape discrimination (PSD) methods have been proposed to suppress the internal α background in LaBr 3 :(Ce) detectors. These methods exploit the small difference in the shape of scintillation pulses from α- and γ-ray interactions. The PSD methods have demonstrated some degree of success, which are limited to only a partial rejection of the α-background while further reduction of the α background is highly desirable for low-background γ-ray measurements. In this work, a novel digital PSD method that significantly improves the rejection of the internal α background was developed. The PSD method is based on the wavelet transform of the scintillation pulses, leading to an almost complete rejection of the α background. This method is very useful for low-level radiation measurements with LaBr 3 :(Ce) detectors involving high-energy γ rays. [ABSTRACT FROM AUTHOR]

Abstract: A γ-ray spectroscopy experiment via the reaction was carried out at KEK-PS in 2005. The K6 beam line and Superconducting Kaon Spectrometer (SKS) were employed to obtain a missing mass spectrum for 12 Λ C. An upgraded germanium detector array, Hyperball2, was introduced to detect γ rays emitted from hypernuclei in coincidence with the reaction. As a result of further analysis, a γ-ray peak at 6048 keV (preliminary) was newly observed and assigned as the M1 transition from the 6-MeV excited state to the ground state. [Copyright &y& Elsevier]

Abstract: Recent results and future directions of the γ-ray spectroscopy of Λ hypernuclei are discussed. A further analysis of the last KEK experiment (E566) has revealed a new γ transition in 12 Λ C at (preliminary), which is ascribed to the transition. At J-PARC, studies will be extended from p-shell to s-shell and sd-shell hypernuclei. In the first part of the J-PARC E13 experiment, we will measure the 4 Λ He( ) transition to study charge-symmetry breaking in the ΛN interaction and investigate the 19 Λ F hypernucleus to study ΛN spin–spin interaction further using one of the sd-shell hypernuclei. In the second part of E13, we will precisely measure the spin-flip value for the 7 Λ Li( ) transition. Beyond E13, we plan to study impurity effects by observing possible changes in nuclear deformation caused by the presence of a Λ in sd-shell hypernuclei, as well as to investigate various heavier Λ hypernuclei in order to precisely determine the energies of Λ single-particle orbits. [Copyright &y& Elsevier]

Abstract: The production process of smooth and crack-free targets by means of constant current electrolysis in organic media, commonly known as molecular plating, was optimized. Using a Nd salt, i.e., [Nd(NO3)3·6H2O], as model electrolyte several constant current density electrolysis experiments were carried out to investigate the effects of different parameters, namely the plating solvent (isopropanol and isobutanol mixed together, pyridine, and N,N-dimethylformamide), the electrolyte concentration (0.11, 0.22, 0.44mM), the applied current density (0.17, 0.3, 0.7, and 1.3mA/cm2), and the surface roughness of the deposition substrates (12 and 24nm). Different environments (air and Ar) were used to dry the samples and the effects on the produced layers were investigated. The obtained deposits were characterized using γ-ray spectroscopy for determining Nd deposition yields, X-ray photoelectron spectroscopy for chemical analysis of the produced surfaces, radiographic imaging for surface homogeneity inspection, atomic force microscopy for surface roughness evaluation, and scanning electron microscopy for surface morphology investigation. The results allowed identifying the optimum parameters for the production of smooth and crack-free targets by means of molecular plating. The smoothest layers, which had an average RMS roughness of ca. 20nm and showed no cracks, were obtained using 0.22mM [Nd(NO3)3·6H2O] plated from N,N-dimethylformamide at current densities in the range of 0.3–0.7mA/cm2 on the smoothest deposition substrate available. [Copyright &y& Elsevier]

Abstract: The production of thin layers by means of constant current or constant voltage electrolysis in organic media is commonly known as molecular plating. Despite the fact that this method has been applied for decades and is known to be among the most efficient ones for obtaining quantitative deposition, a full elucidation of the molecular plating is still lacking. In order to get a general understanding of the process and hence set the basis for further improvements of the method, constant current density electrolysis experiments were carried out in a mixture of isopropanol and isobutanol containing millimolar amounts of HNO3 together with [Nd(NO3)3·6H2O] used as a model electrolyte. The process was investigated by considering the influence of different parameters, namely the electrolyte concentrations (i.e., Nd(NO3)3·6H2O: 0.11, 0.22, 0.44mM, and HNO3: 0.3, 0.4mM), the applied current (i.e., 2mA and 6mA), and the surface roughness of the deposition substrates (i.e., a few tens to several hundreds of nm). The response of the process to changes of these parameters was monitored recording cell potential curves, which showed to be strongly influenced by the investigated conditions. The produced layers were characterized using γ-ray spectroscopy for the evaluation of Nd deposition yields, X-ray photoelectron spectroscopy for chemical analysis of the surfaces, and atomic force microscopy for surface roughness evaluation. X-ray photoelectron spectroscopy results clearly indicate that Nd is present only as Nd3+ on the cathodic surface after molecular plating. The results obtained from this characterization and some basic features inferred from the study of the cell potential curves were used to interpret the different behaviours of the deposition processes as a consequence of the applied variables. [Copyright &y& Elsevier]

High-spin states of Ra ( $\emph{Z}=88$, $\emph{N}=128$) have been investigated through Bi(B, 3n) reaction at an incident beam energy of 55 MeV and Bi(B, 4n) reaction at incident beam energies ranging from 65 to 78 MeV. Based on γγ coincidence data, the level scheme for Ra has been considerably extended up to ~ 33 $\hbar$ spin and 7.2 MeV excitation energy in the present experiment with placement of 28 new γ-transitions over what has been reported earlier. Tentative spin-parity assignments are done for the newly proposed levels on the basis of the DCO ratios corresponding to strong gates. Empirical shell model calculations were carried out to provide an understanding of the underlying nuclear structure. [ABSTRACT FROM AUTHOR]

Abstract: An algorithm for automated analysis of in-situ NaI γ-ray spectra in the marine environment is presented. A standard wavelet denoising technique is implemented for obtaining a smoothed spectrum, while the stability of the energy spectrum is achieved by taking advantage of the permanent presence of two energy lines in the marine environment. The automated analysis provides peak detection, net area calculation, energy autocalibration, radionuclide identification and activity calculation. The results of the algorithm performance, presented for two different cases, show that analysis of short-term spectra with poor statistical information is considerably improved and that incorporation of further advancements could allow the use of the algorithm in early-warning marine radioactivity systems. [Copyright &y& Elsevier]

Abstract: High-resolution spectroscopy has been used to determine the energies and intensities of the γ-rays emitted in the decays of 80mBr and 82gBr, produced by neutron activation of naturally occurring Br. From the observed energies and intensities, improved values for the energies and β-decay feedings of the levels in the daughter nuclides 80Se, 80Kr, and 82Kr have been deduced. [Copyright &y& Elsevier]

Experiments based on the isomer-spectroscopy method were performed using the secondary beam line at RCNP, Osaka University. Recently, a new γ-ray spectroscopy method was established using fusion reaction induced by low-energy RI beam. This method enables us to study high-spin states of nuclei in wider mass region where it is difficult to populate them by using the combination of stable beams and stable targets. This method works well although low production of nuclei, because (1) the combination of beams and targets can be selected with large-reaction cross section and (2) high-S/N measurement can be performed by the event-by-event detection to select the events correlated with RI beam, which reduces background γ rays, competing with γ rays emitted from fusion products. As the first step, high-spin states of 142Pr were studied using fusion reaction induced by low-energy 17N RI beam. Large cross section was obtained by the 130Te(17N,5n) reaction with 4.9 MeV/u 17N beam. Event selection, which was carried out by the event-by-event detection with low-beam intensity of 2×104 pps, enables high-S/N measurement. [ABSTRACT FROM AUTHOR]

Abstract: The updated results from the hypernuclear γ-ray spectroscopy experiment, KEK-E566, are presented in this paper with emphasis on the γ-ray spin assignment. The KEK-E566 experiment was performed at the KEK-PS K6 beam line in 2005. In this experiment, reaction was used to produce hypernuclei. A germanium detector array, Hyperball2, was constructed to detect γ rays emitted from the hypernuclei. Six hypernuclear γ-ray peaks were observed and assigned successfully. [Copyright &y& Elsevier]

Abstract: A new method of clustering for forward-tracking algorithms has been developed to reconstruct the tracks of γ-rays in high-resolution detector systems such as AGATA (Advanced GAmma Tracking Array). This technique, called Deterministic Annealing Filter (DAF), comes from statistical physics and is used in high-energy physics. After a description of the DAF method and of the forward-tracking algorithm, the performance of this clustering method is discussed in terms of photopeak efficiency and peak-to-total ratio obtained with GEANT4 simulations for the AGATA geometry. A comparison with the standard so-called “cone clustering method” shows similar performances with a better photopeak efficiency at high multiplicity for the DAF algorithm. [Copyright &y& Elsevier]

Abstract: Understanding the evolution of Mars requires determining the composition of the surface and atmosphere of the planet. The European Space Agency’s ExoMars rover mission, which is expected to launch in 2016, is part of the Aurora programme. The instruments on the rover will search for evidence of life on Mars and will map a sub-section of the Martian surface, extracting compositional information. Currently our understanding of the bulk composition (and mineralogy) of Mars relies on orbital data from instruments on-board satellites such as 2001 Mars Odyssey, Mars Reconnaissance Orbiter and Mars Express, in addition to in-situ instrumentation on rovers such as Spirit and Opportunity. γ-ray spectroscopy can be used to determine the composition of Mars, but it has yet to be successfully carried out in-situ on Mars. This study describes some of the results obtained from the γ-ray spectrometer on 2001 Mars Odyssey during solar proton events and discusses whether the increased emissions are useful in γ-ray spectroscopy. The study shows that although increased γ-ray emissions were expected from the Martian surface during a solar proton event, they were not detected from orbit probably due to insufficient signal-to-background. However, this does not preclude the possibility of measuring changes in γ-ray flux corresponding to changes in solar activity on the surface of the planet. [Copyright &y& Elsevier]

Abstract: There are a number of future European Space Agency (ESA) and NASA planetary science missions that are in the planning or initial study phases, where the scientific objectives include determining the surface composition, measuring planetary surface heat flow and constraining planetary chronology. The University of Leicester is developing instrumentation for geophysical applications that include γ-ray spectroscopy, γ-ray densitometry and radiometric dating. This paper describes the modelling of a geophysical package, with the Monte Carlo code MCNPX, in order to determine the impact that a neutron source would have on in-situ composition measurements, radiometric dating and, in particular, trace element detection. The suitability of ∅ 2.54×2.54cm LaBr3(Ce) detectors in the geophysical package for in-situ missions was examined. 252Cf, Am–Be and Pu–Be neutron sources were compared in a trade-off study to determine mission suitability, potential for thermal and electric power production, mass and shielding requirements. This study is linked to a parallel examination of the suitability of radioisotope thermal generators for in-situ planetary science applications. The aim of the modelling was to optimise the source type and detector geometry in order to measure the elemental peaks of interest with a precision of 10% or better based on the Poisson statistics of the detected counts above background. [Copyright &y& Elsevier]

Abstract: Planetary radiation environment modelling is important to assess the habitability of a planetary body. It is also useful when interpreting the γ-ray data produced by natural emissions from radioisotopes or prompt γ-ray activation analysis. γ-ray spectra acquired in orbit or in-situ by a suitable detector can be converted into meaningful estimates of the concentration of certain elements on the surface of a planet. This paper describes the verification of a Monte Carlo model developed using the MCNPX code at the University of Leicester. The model predicts the performance of a geophysical package containing a γ-ray spectrometer operating at a depth of up to 5m. The experimental verification of the Monte Carlo model was performed at the FRM II facility in Munich, Germany. The paper demonstrates that the model is in good agreement with the experimental data and can be used to model the performance of an in-situ γ-ray spectrometer. [Copyright &y& Elsevier]

Abstract: γ-Ray spectroscopy, X-ray spectroscopy and γ-ray backscatter densitometry for planetary science applications are three complementary analytical techniques that can be used to determine surface and sub-surface composition, constrain heat flow through a planetary regolith and hence understand more about the processes that formed planetary bodies. Evaluating different detector types and configurations in order to achieve these scientific objectives is a key enabling step for a successful flight instrument development programme. In this study, we evaluate and compare different detector solutions and configurations including: planar and hemispherical CdTe, a CsI(Tl) scintillator, a LaBr3(Ce) scintillator and a HPGe detector. The LaBr3(Ce) detector was chosen as the most suitable detector for an in-situ planetary science mission due to its high-radiation tolerance, low mass compared with HPGe detector systems, its comparable resolution (∼3.4% at 662keV) to compound semiconductors (planar CdTe ∼2.4% at 662keV) and high efficiency. [Copyright &y& Elsevier]

Abstract: An analysis algorithm to correct for the γ-ray true coincidence summing effects for radionuclides decay by cascading photons was developed and implemented in Canberra''s Genie 2000 software in 2001. It has been extended to correct for true coincidence summing effects from low energy γ-rays, KX-rays from electron capturing and internal conversion, and the 511keV positron annihilation photons. Validation of these extensions shows significant improvement in Genie 2000''s true coincidence summing correction capability and the accuracy of nuclide activity measurement. [Copyright &y& Elsevier]

The excited states of 116Sb have been populated using the α induced reaction 115In(α , 3n)116Sb at a beam energy of 40 MeV and investigated via in-beam gamma spectroscopic techniques. A positive parity sequence (B1) of strong M1 transitions with relatively weak crossover E2 transitions, connected to the yrast negative parity rotational band (B2) of 116Sb, has been observed. The experimental B(M1)/B(E2) values for band B1 are found to decrease with angular momentum (I). The origin of this band (B1) has been interpreted in terms of Magnetic Rotation (MR) under the framework of Semi-Classical Model (SCM) and Shears mechanism with Principal Axis Cranking (SPAC) formalism and is assigned a four quasiparticle configuration of π (g 9 / 2)−1 ⊗ ν (g 7/2 /d 5/2)(h 11/2)2. The yrast rotational band B2 is extended up to the band crossing region. [ABSTRACT FROM AUTHOR]

Low-lying states in the even-even 116Sn nucleus have been studied by populating them using the 114Cd(α , 2n)116Sn reaction at the beam energy of 34 MeV. γγ coincidences, directional correlation ratio, and polarization asymmetry measurements were performed using the Indian National Gamma Array (INGA) with a digital data acquisition system. Three-phonon multiplets in the 116Sn nucleus have been investigated. The experimental energy levels are analyzed using theoretical approaches of the interacting boson model (IBM) in the U(5) limit and large-scale shell-model calculations using two different model spaces. [ABSTRACT FROM AUTHOR]

Abstract: The coupling of very efficient gamma-ray arrays with large acceptance (or highly selective) spectrometers in the context of radioactive beams, has pushed away the limits for the exploration of the nuclear chart and opened up new possibilities in nuclear physics studies. At GANIL the EXOGAM array (a large efficiency gamma-ray array) has been coupled to VAMOS (a large acceptance spectrometer) and to SPEG (a highly selective spectrometer) to study many different aspects of nuclear structure and reactions covering the whole nuclear chart. Indeed, this combination has been used to study neutron-rich nuclei toward 54Ca, neutron deficient tin isotopes around A =103, heavy elements around Md and No, reaction mechanism using the borromean light He isotopes, the nuclear structure in the island of inversion around 32Mg, and many other examples in various mass regions and energy regimes. This is also the case for the very efficient large BaF2 array Chateau de Cristal which is frequently coupled to SPEG to study nuclear structure far from stability. In this paper, the various possibilities offered at GANIL with such couplings will be given. In the future, AGATA will be installed at GANIL to exploit the beams produced by the SPIRAL2 facility. Again, it is anticipated that this new generation array will be coupled to spectrometers to better exploit the future beams. [Copyright &y& Elsevier]

Abstract: For high-resolution nuclear spectroscopy using radioactive ion (RI) beams at the RIBF, the SHARAQ spectrometer for projectile-like particles and the GRAPE array for γ-rays are presented. The physics motivation, the specifications and the present status of them are discussed. [Copyright &y& Elsevier]

Abstract: In the paper algorithms for peak searching in one-, two-, three-, and multidimensional spectra (histograms) are derived. They are based on Markov chain smoothing. Though they can be used for any type of nuclear spectra their importance is significant mainly for low-statistics spectra, where standard algorithms fail. The derived procedures are simple and therefore have a low cost in terms of computing time. [Copyright &y& Elsevier]

Abstract: The VeriSpreaderTM radiation detection system will monitor every container passing through a shipping terminal without impeding the flow of commerce by making the radiation measurements during normal container handling. This is accomplished by integrating neutron and spectroscopic γ-ray detectors into a container crane spreader bar, the part of the crane that directly engages the intermodal shipping containers while moving from ship to shore and vice versa. The use of a spectroscopic γ-detector reduces the rate of nuisance alarms due to naturally occurring radioactive material (NORM). The combination of γ and neutron detection reduces the effectiveness of shielding and countermeasures. The challenges in this spreader bar-based approach arise from the harsh environment, particularly the mechanical shock and the vibration of the moving spreader bar, since the measurement is taken while the container is moving. The electrical interfaces in the port environment, from the crane to a central monitoring office, present further challenges. It is the packaging, electronic interfaces, and data processing software that distinguish this system, which is based on conventional radiation sensors. The core of the system is Amptek''s GAMMA-RAD, which integrates a ruggedized scintillator/PMT, digital pulse shaping electronics, electronics for the neutron detector, power supplies, and an Ethernet interface. The design of the VeriTainer system and results from both the laboratory and a proof-of-concept test at the Port of Oakland, California will be presented. [Copyright &y& Elsevier]

Abstract: The analysis of γ-ray spectra using wavelet analysis has recently been demonstrated as a new, promising technique for isotope identification with both NaI and CdZnTe spectra. Wavelet analysis has the potential to benefit over other approaches due to the fact that the signal can simultaneously be analyzed over multiple scales, thus eliminating potential false isotope identifications from artifacts such as the Compton edge and backscatter peaks. This implies that this algorithm is not impacted by variations in the detector''s resolution, which changes with energy. We will present our results of optimizing this algorithm by custom designing wavelets for NaI spectra. Emphasis will be placed on quantifying the merits of these custom wavelets to traditional wavelets by exploring the quality of peak detection and localization, the first step to isotope identification. [Copyright &y& Elsevier]

Abstract: The first results from the stopped beam RISING experimental campaign performed at the GSI laboratory in Darmstadt, Germany, are presented. RISING (Rare ISotope Investigations at GSI) constitutes a major new experimental program in European nuclear structure physics research aimed at using relativistic energy (typically around 1GeV per nucleon) projectile fragmentation reactions to populate nuclei with highly exotic proton-to-neutron ratios compared to the line of beta stability. In its high-efficiency ‘stopped beam’ configuration, the RISING γ-ray spectrometer consists of 105 individual, large volume germanium crystals which view a focal plane in which the exotic nuclei are brought to rest (i.e. ‘stopped’). Here, decays from metastable or ‘isomeric’ states with half-lives in the nano to milliseconds range can be observed, often providing the first spectroscopic information on these exotic nuclear species. This paper introduces the physics aims of the stopped RISING collaboration and presents some technical details on the RISING detector array. Results of initial commissioning experiments are also shown and details of the planned future experimental program are given. [Copyright &y& Elsevier]

Abstract: Undergraduate students at the University of Dallas (UD) have played a significant role in the investigations of the low-lying collective nuclear excitations observed in the Z =52 isotopes. These studies were undertaken using γ-ray spectroscopy following inelastic neutron scattering at the University of Kentucky Low-Energy Nuclear Accelerator Facility. Of particular importance in these investigations is the ability to measure γ-ray Doppler shifts in order to extract lifetimes of excited levels ranging from a few fs to 1ps. UD students have been actively involved in all aspects of the research from operation of the modified CN Van de Graaff accelerator to comparisons of experimental results with model calculations. An overview of undergraduate involvement in this research will be presented, as well as the most recent results of their investigations. [Copyright &y& Elsevier]

Abstract: The Beach Monitoring Steering Group (BMSG) was set up by UKAEA to explore whether improved systems for beach monitoring of radioactive particles are available. The BMSG commissioned the British Geological Survey (BGS) and the Nuclear Geophysics Division of the Kernfysisch Versneller Instituut (KVI/NGD), and other companies, to test their most sensitive system. This paper presents the results of trials in a specially created test facility at UKAEA Harwell with a large BGO detector. The detector''s size and weight mean that it would be suitable for vehicle deployment but would be too large and heavy to carry in areas that could not be accessed by a vehicle. However, it would be possible to use the same methodology that is described here with a smaller detector capable of being carried in a backpack, albeit with reduced sensitivity for particle detection. The approach that we present is also applicable, with modifications, to the detection of offshore particles using a towed seabed detector. [Copyright &y& Elsevier]

Abstract: We present the results of γ-ray measurements on a large 4″×6″ LaCl3:Ce crystal, characterized using radioactive sources over the range 14–3220keV. The response of the crystal was found to be largely linear over the upper 90% of its dynamic range—the deviations at lower energies can be attributed to the shortcomings of the photomultiplier tube (PMT) and is in fact a generic problem when using high-gain PMTs with lanthanum halide scintillators. At 662keV, a measured energy resolution of 4.1% FWHM was recorded at room temperature. In comparison to earlier generations of LaCl3 detectors, the internal background spectrum shows significantly less X-ray, β, γ-ray and α contamination. The integral background count rate in the energy region 20keV–3MeV was determined to be 1.8cm−3 s−1, of which most (1.5cm−3 s−1) can be attributed to the β continuum from 138La and only ∼0.04cm−3 s−1 to the α complex from 227Ac and daughters. Using these data, we have determined the light output of α particles relative to the equivalent energy electrons (or alternately γ-rays) to be, α/γ=0.35±0.02. [Copyright &y& Elsevier]

Abstract: We introduce a direct analytical mathematical method to determine full-energy peak (photopeak) efficiency and coincidence corrections of hyper pure germanium (HPGe) detectors for extended sources. Extensive experimental readings have been carried out. The comparisons between calculations and extended source experiments showed that the relative errors were mostly less than ±3% in the region of photon energies from 60 to 1836keV. [Copyright &y& Elsevier]

Abstract: Joint progress in Cd(Zn)Te detectors, microelectronics and interconnection technologies open the way for a new generation of instruments for physics and astrophysics applications in the energy range from 1 to 1000keV. Even working between −20 and 20°C, these instruments will offer high spatial resolution (pixel size ranging from 300×300μm2 to few mm2), high spectral response and high detection efficiency. To reach these goals, reliable, highly integrated, low noise and low power consumption electronics is mandatory. Our group is currently developing a new full-custom detector front-end ASIC named IDeF-X, for modular spectro-imaging system based on the use of Cd(Zn)Te detectors. We present the most recent version of IDeF-X which is a 16 channels analog readout chip for hard X-ray spectroscopy. It has been processed with the standard AMS 0.35μm CMOS technology. Each channel consists of a charge sensitive preamplifier, a pole zero cancellation stage, a variable peaking time filter and an output buffer. IDeF-X is designed to be DC coupled to detectors having a low dark current at room temperature and is optimized for input capacitance ranging from 2 to 5pF. [Copyright &y& Elsevier]