•We report about experimental results of a new tritium activity monitoring system using the BIXS method.•The system is compact and easy to implement. It has a small dead volume of about 28cm3 and can ...be used in a flow-through mode.•Gold coated surfaces are used to improve significantly count rate stability of the system and to reduce stored inventory.
To develop a convenient tool for in-line tritium gas monitoring, the TRitium Activity Chamber Experiment (TRACE) was built and commissioned at the Tritium Laboratory Karlsruhe (TLK). The detection system is based on beta-induced X-ray spectrometry (BIXS), which observes the bremsstrahlung X-rays generated by tritium decay electrons in a gold layer. The setup features a measuring chamber with a gold-coated beryllium window and a silicon drift detector. Such a detection system can be used for accountancy and process control in tritium processing facilities like the Karlsruhe Tritium Neutrino Experiment (KATRIN). First characterization measurements with tritium were performed. The system demonstrates a linear response between tritium partial pressure and the integral count rate in a pressure range of 1Pa up to 60Pa. Within 100s measurement time the lower detection limit for tritium is (143.63±5.06)·104Bq. The system stability of TRACE is limited by a linear decrease of integral count rate of 0.041%/h. This decrease is most probably due to exchange interactions between tritium and the stainless steel walls. By reducing the interaction surface with stainless steel, the decrease of the integral count rate was reduced to 0.008%/h. Based on the first results shown in this paper it can be concluded that TRACE is a promising complement to existing tritium monitoring tools.
An unavoidable category of molecular species in large-scale tritium applications, such as nuclear fusion, are tritium-substituted hydrocarbons, which form by radiochemical reactions in the presence ...of (circulating) tritium and carbon (mainly from the steel of vessels and tubing). Tritium-substituted methane species, CQ
4
(with Q = H,D,T), are often the precursor for higher-order reaction chains, and thus are of particular interest. Here we describe the controlled production of CQ
4
carried out in the CAPER facility of the Tritium Laboratory Karlsruhe, exploiting catalytic reactions and species enrichment via the CAPER integral permeator. CQ
4
was generated in substantial quantities (>1000 cm
3
at ~850 mbar, with CQ
4
content of up to ~20%). The samples were analyzed using laser Raman and mass spectrometry to determine the relative isotopologue composition and to trace the generation of tritiated chain hydrocarbons.
•We have set up a new test device for measuring of tritiated gas samples.•The device is very compact and easy and reliable in operation.•Easy integration in flow-through systems.•The device has been ...operated at Tritium Laboratory Karlsruhe for several months.•The lower detection limit has been improved with regard to predecessors experiments.
A commonly used activity monitoring method for tritium accountancy and process monitoring in tritium technology is ionization counting. Despite the wide use of ionization chambers (IC), they have several drawbacks like a strong gas species and pressure dependency. Furthermore, if compact systems are needed, there is also the necessity for process gas pressures >10kPa. To encounter these drawbacks, the TRitium Activity Chamber Experiment (TRACE) has been developed at the Tritium Laboratory Karlsruhe (TLK) as a compact tritium monitor based on the beta induced X-ray spectrometry (BIXS) principle.
TRACE can be used as an accountancy tool in tritium-processing facilities like the KArlsruhe TRItium Neutrino (KATRIN) experiment. In contrast to ICs TRACE shows a linear response to pressure changes up to approx. 1kPa. The results of performed flow-through measurements confirm that TRACE is a complement for ICs in the low-pressure regime. Furthermore the gas species dependency of TRACE is investigated both with tritium measurements and with Monte Carlo simulations.
The β-ray induced X-ray spectrometry (BIXS) is a promising technique to monitor the tritium concentration in a fuel cycle of a fusion reactor. For in-situ measurements of high level tritiated water ...by bremsstrahlung counting, the characteristics of a low-noise silicon drift detector (SDD) have been examined at the Tritium Laboratory Karlsruhe (TLK). In static measurements with constant sample volume and tritium concentration, the bremsstrahlung spectra of tritiated water samples in a concentration range of 0.02 to 15 MBq/ml have been observed. The volume has been kept constant at 5 cm
3
. The observed spectra are well above the noise threshold. In addition to X-rays induced by β-rays, the spectra feature X-ray fluorescence peaks of the surrounding materials. No indications of memory effects have been observed. A linear relation between the X-ray intensity and the tritium concentration was obtained and the lower detection limit of the setup has been determined to 1 MBq ml
-1
, assessed by the Currie criterion. In addition, the spectra obtained experimentally could be reproduced with high agreement by Monte-Carlo simulations using the Geant4-toolkit. It was found that the present detection system is applicable to non-invasive measurements of high-level tritiated water and the SDD is a convenient tool to detect the low energy bremsstrahlung X-rays.
In this work, we present the first spectroscopic measurements of conversion electrons originating from the decay of metastable gaseous 83mKr with the Karlsruhe Tritium Neutrino (KATRIN) experiment. ...The obtained results represent one of the major commissioning milestones for the subsequent direct neutrino mass measurement with KATRIN. The successful campaign demonstrates the functionalities of the KATRIN beamline. Precise measurement of the narrow K-32, L3-32, and N2,3-32 conversion electron lines allowed to verify the eV-scale energy resolution of the KATRIN main spectrometer necessary for competitive measurement of the absolute neutrino mass scale.
Abstract The neutrino mass experiment KATRIN requires a stability of 3 ppm for the retarding potential at − 18.6 kV of the main spectrometer. To monitor the stability, two custom-made ultra-precise ...high-voltage dividers were developed and built in cooperation with the German national metrology institute Physikalisch-Technische Bundesanstalt (PTB). Until now, regular absolute calibration of the voltage dividers required bringing the equipment to the specialised metrology laboratory. Here we present a new method based on measuring the energy difference of two $$^{83{\mathrm{m}}}$$ 83m Kr conversion electron lines with the KATRIN setup, which was demonstrated during KATRIN’s commissioning measurements in July 2017. The measured scale factor $$M=1972.449(10)$$ M=1972.449(10) of the high-voltage divider K35 is in agreement with the last PTB calibration 4 years ago. This result demonstrates the utility of the calibration method, as well as the long-term stability of the voltage divider.
The neutrino mass experiment KATRIN requires a stability of 3 ppm for the retarding potential at − 18.6 kV of the main spectrometer. To monitor the stability, two custom-made ultra-precise ...high-voltage dividers were developed and built in cooperation with the German national metrology institute Physikalisch-Technische Bundesanstalt (PTB). Until now, regular absolute calibration of the voltage dividers required bringing the equipment to the specialised metrology laboratory. Here we present a new method based on measuring the energy difference of two 83mKr conversion electron lines with the KATRIN setup, which was demonstrated during KATRIN’s commissioning measurements in July 2017. The measured scale factor M=1972.449(10) of the high-voltage divider K35 is in agreement with the last PTB calibration 4 years ago. This result demonstrates the utility of the calibration method, as well as the long-term stability of the voltage divider.
We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity ...gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic endpoint at 18.57 keV gives an effective neutrino mass square value of \((-1.0^{+0.9}_{-1.1})\) eV\(^2\). From this we derive an upper limit of 1.1 eV (90\(\%\) confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of two and provides model-independent input to cosmological studies of structure formation.
The determination of the neutrino mass is one of the major challenges in astroparticle physics today. Direct neutrino mass experiments, based solely on the kinematics of beta-decay, provide a largely ...model-independent probe to the neutrino mass scale. The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to directly measure the effective electron antineutrino mass with a sensitivity of 0.2 eV 90% CL. In this work we report on the first operation of KATRIN with tritium which took place in 2018. During this commissioning phase of the tritium circulation system, excellent agreement of the theoretical prediction with the recorded spectra was found and stable conditions over a time period of 13 days could be established. These results are an essential prerequisite for the subsequent neutrino mass measurements with KATRIN in 2019.
In this work, we present the first spectroscopic measurements of conversion electrons originating from the decay of metastable gaseous \(^\mathrm{83m}\)Kr with the Karlsruhe Tritium Neutrino (KATRIN) ...experiment. The results obtained in this calibration measurement represent a major commissioning milestone for the upcoming direct neutrino mass measurement with KATRIN. The successful campaign demonstrates the functionalities of the full KATRIN beamline. The KATRIN main spectrometer's excellent energy resolution of ~ 1 eV made it possible to determine the narrow K-32 and L\(_3\)-32 conversion electron line widths with an unprecedented precision of ~ 1 %.
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