Electromagnetic transition strengths in 33 S

Journal of Instrumentation

A : In the EXILL campaign a highly efficient array of high purity germanium (HPGe) detectors was operated at the cold neutron beam facility PF1B of the Institut Laue-Langevin (ILL) to carry out nuclear structure studies, via measurements of γ-rays following neutron-induced capture and fission reactions. The setup consisted of a collimation system producing a pencil beam with a thermal capture equivalent flux of about 10 8 n s −1 cm −2 at the target position and negligible neutron halo. The target was surrounded by an array of eight to ten anti-Compton shielded EXOGAM Clover detectors, four to six anti-Compton shielded large coaxial GASP detectors and two standard Clover detectors. For a part of the campaign the array was combined with 16 LaBr 3 :(Ce) detectors from the FATIMA collaboration. The detectors were arranged in an array of rhombicuboctahedron geometry, providing the possibility to carry out very precise angular correlation and directional-polarization correlation measurements. The triggerless acquisition system allowed a signal collection rate of up to 6 × 10 5 Hz. The data allowed to set multi-fold coincidences to obtain decay schemes and in combination with the FATIMA array of LaBr 3 :(Ce) detectors to analyze half-lives of excited levels in the pico-to microsecond range. Precise energy and efficiency calibrations of EXILL were performed using standard calibration sources of 133 Ba, 60 Co and 152 Eu as well as data from the reactions 27 Al(n,γ) 28 Al and 35 Cl(n, γ) 36 Cl in the energy range from 30 keV up to 10 MeV.

AIP Conference Proceedings, 2005

The energies of eight gamma rays in the 36 Cl level scheme have been measured with high precision using the 35 Cl(n,γ) reaction and the GAMS4 spectrometer. From these energies, a skeleton decay scheme for 36 Cl was constructed, and the binding energy of 36 Cl was determined to higher precision than previously. It is shown that using this new information, binding energy determination from Ge detector experiments for other nuclei can also be made with higher precision than now available. The measurement of additional weaker 36 Cl gamma rays is continuing.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1997

This paper presents a method for determining gamma-ray energies with a precision similar to that of the primary standards. The method consists of both an experimental procedure which employs Ge detectors, and the statistical treatment of data. An actual example with lSYGd p-decay illustrates its use.

Journal of Instrumentation, 2017

The procedure for obtaining the updated version of the recommended gamma-ray transition energies for detector calibration is described. The energies were recalculated to account for the 2002 CODATA Recommended Values of Fundamental Physical Constants. The re-evaluation methodology considered the statistical correlations and used the appropriate covariance matrices in all steps.

Nukleonika

LaBr 3 :Ce,CeBr 3 and GAGG:Ce scintillators were investigated and the determined characteristics were compared with those obtained for the well-known and widely used CsI:Tl and NaI:Tl crystals. All the detectors were of the same size of 10 × 10 × 5 mm 3. The aim of this test study was to single out scintillation detectors most suitable for -ray spectrometry and -ray emission radial profi le measurements in high-temperature plasma experiments. Decay time, energy resolution, non-proportionality and full energy peak detection effi ciency were measured for -ray energies up to 1770 keV. Due to their good energy resolution, short decay time and high detection effi ciency for MeV gamma rays, LaBr 3 :Ce and CeBr 3 scintillators are proposed as the best candidates for use especially under conditions of high count rates, which are expected in the forthcoming DT experiments.

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment

The response of AGATA segmented HPGe detectors to gamma rays in the energy range 2-15 MeV was 29 measured. The 15.1 MeV gamma rays were produced using the reaction d( 11 B,n ) 12 C at E beam = 19.1 MeV, 30 while gamma-rays between 2 to 9 MeV were produced using an Am-Be-Fe radioactive source. The energy 31 resolution and linearity were studied and the energy-to-pulse-height conversion resulted to be linear within 32 0.05%. Experimental interaction multiplicity distributions are discussed and compared with the results of 33 Geant4 simulations. It is shown that the application of gamma-ray tracking allows a suppression of 34 background radiation following neutron capture by Ge nuclei. Finally the Doppler correction for the 15.1 35 MeV gamma line, performed using the position information extracted with Pulse-shape Analysis, is 36 discussed. 37 38 39 65 Shape Algorithms [19-28]. The energy and direction of 66 the individual photons are extracted through dedicated 67 gamma-ray tracking algorithms [29-32]. It should be 68 remarked that the individual interaction points are 69 extracted with sub-segment precision, which 70 experimentally turns out to be better than a 3D 71 Gaussian with 5 mm FWHM in each direction (see for 72 instance [33-36]). In order to achieve this goal, 73 remarkable effort has been concentrated on the 74 characterization of highly-segmented HPGe detectors 75 [37-52]. 76 The possibility to improve the performances of a 77 gamma-ray spectrometer at high energies using 85 LaBr 3 :Ce scintillation detector. Lower panel: schematic 86 representation of the Am-Be-Fe source. 87 88 The gamma-ray spectrum acquired using the Am-Be-89 Fe source is displayed in Figure 2 and the gamma lines 90 used for the analysis are labeled according to the 91 reaction which originated them. These data allowed the 92 calibration of the detectors and a check of the linearity 93 and energy resolution of the AGATA detectors. The 94 average counting rate per crystal was 0.9 kHz for the 95 case of source measurement and 1.2 kHz for the in-96 beam test. 97 98 99 100 101 102 103 104

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2004

The absolute intensities of 36 c-rays in the energy range of 292-8579 keV from neutron capture in chlorine were remeasured at the Budapest cold neutron prompt gamma activation analysis facility. The 1% level of accuracy of the nitrogen standard was practically achieved for the relative intensity of most of the 36 Cl c-rays, thus making chlorine a useful secondary standard for efficiency calibration of germanium detectors.

2007

Revista Mexicana de Física

The calibrations of the full-energy peak efficiency, energy, and energy resolution are the main factors for successful quantitative gamma-ray analysis. The first purpose of this work is to present the calibration factors for 2"x2" ScintiPack Model 296 NaI(Tl). The detector was irradiated with radioactive sources ( 137 Cs, 60 Co, 152 Eu point sources, and 241 Am, 22 Na cylinder-shaped sources) that emit photons at different energies from 59 keV to 1408 keV. The detector efficiency was also evaluated using Geant4 based GATE simulation. The analytical equations for efficiency calibration were found out with their parameters. Since the results obtained from the experimental and simulation were compatible with each other and with literature results, then the simulation model was modified into the novel scintillation detector systems such as; LaBr3, GAGG(Ce), and SrI2 .