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For ensuring compliance with a Comprehensive Nuclear-Test-Ban Treaty, it is essential to have advanced monitoring technologies for the detection of nuclear testing and to ensure that detected signals are well understood. Traditionally, Xe, Xe, and Xe originating from fission are analyzed to determine their possible origin. This work explores the non-traditional isotope Xe ( T = 36.346(3) d) as it can occur as emission from research reactors, is used in medical procedures, and tracer experiments. It is a good candidate for quality assurance and control and inter-laboratory comparisons. Xe was produced via neutron activation and measured with a high purity germanium detector as well as a β-γ-coincidence detector system. [ABSTRACT FROM AUTHOR]

One of the most influential alchemical authors of the early modern period was Michael Sendivogius whose early life is shrouded in mystery. He may be labelled the most famous Polish scientific writer between Copernicus and Marie Skłodowska-Curie, but because of the difficulties involved in researching the biography of any alchemist, there has been relatively little interest in him among Polish historians. The early work of Roman Bugaj (author of the still fundamental monograph) and Włodzimierz Hubicki (who made his research available to the international community) has been continued only by the English-born Zbigniew Szydło and the author of this article. The roots of many legends about Sendivogius were three mid-17th century short biographies, none of which is trustworthy, so it is crucial to verify the received myth and the version constructed in the 1960's and 1970's with primary sources and evidence from the recent "new historiography of alchemy". The present article examines them in the light of newly discovered sources and reinterpretation of the old ones. The genealogy of the Seędzimir family is discussed at length to show that Sendivogius most probably was not its member but only a pretender in order to assume (or prove) the status of a nobleman. Several possible hypotheses about his origins are presented. He is known to have studied at three universities (Leipzig, Vienna and Altdorf) but authors of early panegyrics dedicated to Sendivogius list more universities which he may have attended. The most interesting is that of Cambridge, listed as the first one, because practically no Poles or Czechs went there at the time. Finally, his marriage to Veronica Stiebar, a wealthy widow of a Franconian knightly family, and her interesting family relationships (links to Erasmus, Camerarius, Paracelsus and the original Doctor Faustus) are discussed. The period covered is that before Sendivogius moved to Prague in about 1597, having already been a courtier of Rudolf II since early 1594. [ABSTRACT FROM AUTHOR]

Rare isotope beams of many elements can be difficult or impossible to obtain at ISOL facilities due to their high melting points or chemical reactivity, but they are easily produced by projectile fragmentation and in-flight separation, a technique that rapidly produces fragments lighter than the projectile in a chemistry-free manner. Until recently, such high-energy projectile fragments could not be reduced to the thermal energies necessary for precision mass measurements in Penning traps. The Low Energy Beam and Ion Trap (LEBIT) facility at the National Superconducting Cyclotron Laboratory (NSCL) has demonstrated that projectile fragment beams can be thermalized and measured in a high-precision Penning trap. Since 2005, over 30 isotopes have been measured with LEBIT, including several isotopes of elements which are difficult for ISOL facilities to produce, such as Fe, Co, Si, Br, and S. These measurements have contributed to our understanding of nuclear structure, nuclear astrophysics, and fundamental symmetries. Some recent highlights include the discovery of an isomeric state in Fe, testing the Isobaric Mass Multiplet Equation (IMME) with the A = 32, T = 2 quintet with a measurement of Si, probing out to the proton dripline with Br, and studying the N = 28 shell closure with measurements of S. Results of these measurements will be discussed, along with the technical developments which made them possible. [ABSTRACT FROM AUTHOR]

The low-energy beam and ion trap facility LEBIT at NSCL/MSU is at present the only facility where precision experiments are performed with stopped rare isotope beams produced by fast-beam fragmentation. LEBIT combines high-pressure-gas stopping with advanced ion manipulation techniques to provide brilliant low-energy beams. So far these beams have mainly been used for mass measurements on short-lived rare isotopes with a 9.4T Penning trap mass spectrometer. Recent examples include 70 mBr , located at the proton dripline, 32Si and the iron isotopes 63-65Fe . While the measurement of 32Si helps to solve a long-standing dispute over the validity of the isobaric multiplet mass equation (IMME) for the A = 32 , T = 2 multiplet, the mass measurements of 65 m,gFe marked the first time a nuclear isomeric state has been discovered by Penning trap mass spectrometry. [ABSTRACT FROM AUTHOR]

The low-energy beam and ion trap facility LEBIT at the NSCL at MSU has demonstrated that rare isotopes produced by fast-beam fragmentation can be slowed down and prepared such that precision experiments with low-energy beams are possible. For this purpose high-pressure gas-stopping is employed combined with advanced ion manipulation techniques. Penning trap mass measurements on short-lived rare isotopes have been performed with a 9.4 T Penning trap mass spectrometer. Examples include 66As, which has a half-live of only 96 ms, and the super-allowed Fermi-emitter 38Ca, for which a mass accuracy of 8 ppb (280 eV) has been achieved. The high accuracy of this new mass value makes 38Ca a new candidate for the test of the conserved vector current hypothesis. [ABSTRACT FROM AUTHOR]

A linear gas stopping cell has been implemented at the NSCL as part of the Low Energy Beam and Ion Trap (LEBIT) facility. The gas stopping cell is used to convert relativistic ions into low energy ions suitable for use in ion trap experiments. A common undesired property of such systems is the production of beam contaminants through charge exchange of gas impurities with the He + ions produced in the stopping process. These contaminants are of particular concern for Penning trap mass spectrometry, where the simultaneous trapping of ions with different masses can cause unwanted shifts in the measured cyclotron frequency of the desired ions. In order to minimize such effects, a multi-stage beam purification system has been implemented at LEBIT. [ABSTRACT FROM AUTHOR]

Abstract A prototype stilbene beta cell has been designed, manufactured, tested, and compared to a plastic scintillator beta cell used for nuclear explosion monitoring of radioxenon. Measurements of the four isotopes of interest show similar responses for both the plastic scintillator and stilbene cell. However, we show that the stilbene cell exhibits 100-times smaller memory effect than the plastic cell, a capability that is of interest in nuclear explosion monitoring because it improves detection sensitivity, allowing for decreased time between measurements. The resolution of the stilbene cell is improved slightly (decreased by 2.2 keV at 129 keV) when compared to the plastic scintillator cell. The efficiency of the stilbene cell is lower than that of the plastic by an average 15%. These results suggest that the light-collection efficiency of the stilbene cell could be improved in future designs. Pulse shape discrimination analysis decreases the minimum detectable concentration by 1%. The use of this geometry allows for a simple replacement of the plastic cells currently used in the field versus a complete overhaul of the existing radioxenon monitoring stations. [ABSTRACT FROM AUTHOR]

Abstract: A technique for precise control of ion injection into a Penning trap is presented, based on the employment of an drift motion of the ion in the strong magnetic field in which the Penning trap is located. An electric dipole field with variable strength and orientation allows for precise placement of the ion in the radial plane of the trap. This method allows for fast preparation of an ion’s magnetron motion, as used, for example, in the time-of-flight cyclotron resonance detection technique. [Copyright &y& Elsevier]

We evaluate the ability of the Canberra Alpha Beta Environmental Continuous Air Monitor (ECAM) to detect and quantify airborne radiological contamination. The ECAM essentially consists of a passively-implanted planar silicon (PIPS) detector near a particulate filter through which outside air is pulled. Three years' worth of background measurements on three different systems were assessed and calibrated to compensate for changing conditions and develop an average background response for the systems. The ECAM was also exposed to several radionuclides of interest, including 235U and 239Pu, to measure the response to alpha and beta particle sources. Both standard calibration sources and custom sources consisting of aqueous radioisotope solutions absorbed into clean filters. The ECAM responses to these sources were then scaled to quantities of interest and injected on the averaged background. Various alarm algorithms were evaluated on the source-injected spectra for minimum detectable air concentration for a given false alarm rate. Even in the worst case, the ECAM was able to detect radionuclides of interest at 10% of the Derived Response Level (DRL) for each isotope based on early-phase Protective Action Guides (PAG). Quantification of the radionuclides was also evaluated for the various algorithms, with mixed results, but overall clearly indicating the optimal algorithms for alpha and beta particle alarm and quantification. Finally, a limited evaluation of the beta particle detection efficiency points to a detection energy threshold of approximately 290 keV. • Continuous air monitor able to measure airborne isotopes of concern to 10% of derived response levels or less. • Summing counts in a single region of interest produces best sensitivity to alpha emitters. • Predicting beta counts based on background alpha counts and decay chains produces the best sensitivity to beta emitters. • Beta particle lower energy threshold estimated to be approximately 290 keV for planar silicon detector. [ABSTRACT FROM AUTHOR]

Two isotopically-characterized targets of high-purity (99.961±0.002%) 238U metal and a neutron dosimetry package were exposed to a pulsed neutron irradiation using the Godiva IV critical assembly at the National Criticality Experiments Research Center to measure the integral fission product yields produced in a Watt fission neutron-energy spectrum. Following irradiation, the fissioned targets were counted with two broad energy germanium detectors. Estimates of the total fissions for each target were made using measurements of well-known fission products. The total number of fissions in each target were then used to measure the fission yields of 33 fission products, 18 of which are published as new measurements. Twelve of the 18 isotopes were in agreement with ENDF/B-VIII.0 using the zeta test and treating ENDF/B-VIII.0 as the true mean: 84mBr, 93Y, 94Y, 104Tc, 134I, 135I, 138Xe, 141Ba, 142Ba, 142La, 146Ce, and 149Nd. The ENDF/B-VIII.0 fission yield for 139Ba was only slightly outside of 1- σ relative to the uncertainty measured in this work. Uncertainties for 5 fission product yields were markedly improved over those reported in ENDF/B-VIII.0: 128Sn, 129Sb, 130gSb, 131mTe, and 133I. The fission yields measured for 128Sn, 131mTe, and 133I were in good agreement with the ENDF/B-VIII.0 predicted fission yields. However, fission yields measurements of the isotopes 129Sb, and 130gSb deviated from the ENDF/B-VIII.0 value. Both of these isotopes reside near the doubly magic nuclear shell closures of 50 protons and 82 neutrons. These fission yields may be suppressed because of the odd-odd nuclear structure of 130gSb and the odd-even structure of 129Sb and isomer splitting. Comparisons to other recent work and a brief review with citations are included to support this conclusion. [ABSTRACT FROM AUTHOR]

Abstract Radioxenon detection is an important component of the verification regime for the Comprehensive Nuclear-Test-Ban Treaty. We developed and validated a new model in MCNPX-PoliMi to simulate the decay of various radioxenon isotopes and the detector response of a variety of detector types. The model was validated using calibration data from a plastic and NaI(Tl) beta–gamma coincidence detector and the results are presented. The results of this validation show that this model can also be used as a tool to produce training spectra and as a method to calibrate radioxenon detection systems. [ABSTRACT FROM AUTHOR]

Radioxenon emissions from fission-based radiopharmaceutical production are a major source of background concentrations affecting the radioxenon detection systems of the international monitoring system (IMS). Collection of real-time emissions data from production facilities makes it possible to screen out some medical isotope signatures from the IMS radioxenon data sets. This paper describes an effort to obtain and analyze real-time stack emissions data with the design, construction and installation of a small stack monitoring system developed by a joint CTBTO-IDC, BATAN, and Pacific Northwest National Laboratory team at the BaTek medical isotope production facility near Jakarta, Indonesia. [ABSTRACT FROM AUTHOR]

Fission product yields are critical data for a variety of nuclear science and engineering applications; however, independent yields have not been extensively measured to date. We have previously documented a methodology to measure the cumulative and independent fission product yields using gamma spectrometry and nuclide buildup and decay modeling, and numerical optimization. We have produced fission products by bombarding U with 14.1 MeV neutrons and made measurements of fission product yields. In this paper, we summarize our approach, describe initial experiments, and present preliminary results where we have determined nine fission product yields for long-lived nuclides. [ABSTRACT FROM AUTHOR]

PNNL developed a beta-gamma simulator (BGSim) that incorporated GEANT-modeled data sets from radioxenon decay chains, as well as functionality to use nuclear detector-acquired data sets to create new beta-gamma spectra with varying amounts of background, Xe, Xe, Xe, Xe, and Rn and its decay products. After BGSim was developed, additional uses began to be identified for the program output: training sets of two-dimensional spectra for data analysts at the IDC and other NDC, and spectra for exercises such as the Integrated Field Exercise 2014 held in Jordan at the Dead Sea. [ABSTRACT FROM AUTHOR]