An overview on the status and function of current spectrometry hardware, of detectors having energy-dispersive (spectrometric) properties as well as of the latest developments in quantitative spectrometry software is presented. Making extensive use of modern computing power, new strategies in high-precision spectrum analysis have been developed which enhance the quality of results and also open new fields of spectrometric applications. Three principles have been newly introduced to spectrum analysis software:

An overview of the latest developments in quantitative spectrometry software is presented. New strategies and algorithms introduced are characterized by buzzwords "Physics, no numerology", "Fuzzy logic" and "Repeated analyses". With the implementation of these new ideas one arrives at software capabilities that were unreachable before and which are now realized in the GAMMA-W, SODIGAM and ALPS packages.

An overview of the latest developments in quantitative spectrometry software is presented.

Abstract An overview of the status and function of current spectrometry hardware, detectors having energy‐dispersive (spectrometric) properties as well as the latest developments in quantitative spectrometry software is presented.

An extended U/Pb-assembly was irradiated with an extracted beam of 2.52 GeV deuterons from the Nuclotron accelerator of the Laboratory of High Energies within the JINR in Dubna, Russia. The lay-out of this experiment and first results are reported. The Pb-target (diameter 8.4 cm, length 45.6 cm) is surrounded by a nat U-blanket (206.4 kg) and used for transmutation studies of hermetically sealed radioactive samples of 129 I, 237 Np, 238 Pu and 239 Pu. Estimates of transmutation rates were obtained as result of measurements of gamma-activities of the samples. Information about the spatial and energy distribution of neutrons in the volume of the lead target and the uranium blanket was obtained with sets of activation threshold detectors (Al, Y and Au) and solid state nuclear track detectors (SSNTD). An electronic 3 He neutron detector was tested on-line. A comparison of experimental data with theoretical model calculations using the MCNPX program was performed yielding satisfactory results.

A spallation neutron source consisting of an extended lead target surrounded with a paraffin moderator irradiated by 1, 1.5, and 2.0GeV protons is used to study neutron capture and transmutation reaction rates in 139La, 129I and 237Np samples in secondary neutron fluences. Reaction rates are obtained by activation analysis using HPGe detectors. The results are compared with calculations using a cascade-evaporation model.

Transmutation experiments have been carried out using the NUCLOTRON, a new accelerator for relativistic particles. The experiments were carried out in the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna, Russian Federation. Earlier experiments using an 8 cm circle divide Pb-target of 20 cm length and surrounded by 6 cm paraffin (GAMMA-2 target) have been continued to study the transmutation of La-139 and the highly radiotoxic radwaste nuclides I-129 and Np-237 using spallation neutrons produced by relativistic protons with energies 0.5 GeV <= E-p <= 4.15 GeV. Results of previous experiments were complemented with additional results, thus yielding data systematics with small uncertainties over the probably commercially relevant energy range of 0.5 GeV <= E-p <= 1.0 GeV and also in the scientifically interesting range above I GeV. Moreover, neutron density distributions in irradiations with 0.65 GeV, 1 GeV and 3.7 GeV protons were determined on the surface of the paraffin moderator for two energy regimes of slow and intermediate/fast neutrons. A large set of high quality experimental data with small uncertainties has been generated that can serve as benchmark data for modelling purposes.

Following a fast chemical separation of Ru isotopes from a fission-product mixture, 105mRh was periodically extracted from its precursor (4.44-h 105Ru) for measurements of its half-life. The new value for the T1/2 of 105mRh of (43.0±0.3)s resolves the long-standing conflict in the literature between the two earlier measured values of 45 and 30s.

Although the spontaneous-fission properties of heavy actinides have been studied for well over 35 years, many interesting and informative details continue to come into light. During the last decade, the spontaneous fission of Cf-252, Fm-257 and Md-260 has been extensively investigated at the Philipps University of Marburg (1-4), by means of a gadolinium-doped liquid scintillation tank for neutron counting and surface barrier detectors for fission fragment detection. The three nuclides represent the transition from the well-known asymmetric fission yield distribution, as it is characteristic for Cf-252, to a much more symmetrical one, found in the fission of Md-260. Therefore, trends in the dynamical changes of fission properties have been derived from these studies. For the spontaneous fission of Cf-252;and 260Md, it was already shown that different fission modes, as proposed by theoretical calculations of Brosa et al. (5), could be separated, using the correlation between the neutrons emitted in a fission event and both the observed fission-fragment mass and the total kinetic energy (1, 2). In the case of 257Fm, no theoretical calculations for fission modes exist. However, from the fission properties of the two surrounding actinides, one can expect at least three different fission modes, namely two "standard" and the "supershort" made. In this paper, results from the recent 257Fm experiment will be presented and compared to systematics extracted from the fission properties of other heavy actinides.

Although the spontaneous-fission properties of heavy actinides have been studied for well over 35 years, many interesting and informative details continue to come into light. During the last decade, the spontaneous fission of 252Cf, 257Fm and 260Md has been extensively investigated at the Philipps University of Marburg (1–4), by means of a gadolinium-doped liquid scintillation tank for neutron counting and surface barrier detectors for fission fragment detection. The three nuclides represent the transition from the well-known asymmetric fission yield distribution, as it is characteristic for 252Cf, to a much more symmetrical one, found in the fission of 260Md. Therefore, trends in the dynamical changes of fission properties have been derived from these studies. For the spontaneous fission of 252Cf and 260Md, it was already shown that different fission modes, as proposed by theoretical calculations of Brosa et al. (5), could be separated, using the correlation between the neutrons emitted in a fission even...

A procedure for the determination of Pb-210 is presented, which is based upon the beta-spectrometric assay (utilizing a liquid-scintillation counter) of Bi-210 in radioactive equilibrium. Separation of Bi-210 from the sample matrix as well as from other beta-emitters is achieved quickly, simply and selectively using a purge and trap technique based upon the generation and subsequent absorption of BiH3 on a prepared filter paper. Advantages of this method include: 1) radioactive equilibrium between Pb-210 and Bi-210 is relatively quickly attained; 2) the external background signal in liquid-scintillation counting is very low, 3) no quenching corrections are necessary, as the sample matrix is invariant; and 4) because of the high counting efficiency, only short measuring limes are required.

Gamma-ray lines following the decay of 234mPa were assayed via high-purity germanium-crystal (HPGe) spectrometry of analytical-grade foils of depleted uranium metal. Absolute intensities were determined for the strongest lines (Iγ ⩾ 0.002%), with special emphasis on the 1001 keV line, which is often used for either assay or normalization purposes. The Iγ value derived for this latter line was independently confirmed in two further measurements, in which its intensity relative to the 185.7 keV gamma line which accompanies the decay of 235U was compared. Our new value for the absolute intensity of this line Iγ (1001 keV) is (0.845 ± 0.021)%, which is over 1.4 times greater than the currently-accepted value.

Gamma-ray lines following the decay of Pa-234m were assayed via high-purity germanium-crystal (HPGe) spectrometry of analytical-grade foils of depleted uranium metal. Absolute intensities were determined for the strongest lines (I(gamma) greater-than-or-equal-to 0.002%), with special emphasis on the 1001 keV line, which is often used for either assay or normalization purposes. The I(gamma) value derived for this latter line was independently confirmed in two further measurements, in which its intensity relative to the 185.7 keV gamma line which accompanies the decay of U-235 was compared. Our new value for the absolute intensity of this line I(gamma) (1001 keV) is (0.845 +/- 0.021)%, which is over 1.4 times greater than the currently-accepted value.