To determine the radiation processing efficiency of a cobalt-60 source at the end of its useful life for products that require low radiation doses, the irradiation doses absorbed by the products were ...determined using the Fricke dosimeters and UV–visible spectrophotometer. Garlic “Allium sativum L.” was considered in this study because of its virtue in treating different diseases such as cancer and cardiovascular diseases and high cholesterol-lowering effect and the short time required for its irradiation. Therefore, boxes containing garlic were irradiated at 50, 100, and 150 Gy for 7, 18, and 29 min, respectively. The relative absorbed dose mapping showed a symmetrical distribution in the front and back sides of the garlic box. Thus, the cobalt-60 source was revealed to be efficient in the irradiation of garlic even at the end of its useful life.
•The good irradiation practice of a cobalt-60 source at the end of its useful life was confirmed using the Fricke dosimeters.•The efficiency of a cobalt-60 source at the end of its useful life in processing products that require low radiation doses was demonstrated.•The dose uniformity ratio for garlic and rockwool phantom was deduced.
The Enriched Xenon Observatory (EXO) will search for double beta decays of
136Xe. We report the results of a systematic study of trace concentrations of radioactive impurities in a wide range of raw ...materials and finished parts considered for use in the construction of EXO-200, the first stage of the EXO experimental program. Analysis techniques employed, and described here, include direct gamma counting, alpha counting, neutron activation analysis, and high-sensitivity mass spectrometry.
Highlights • A comparison between the EOS imaging system and CT scanner is proposed. • The comparison leads to lower doses with EOS imaging system than with CT scanner. • The EOS system is less ...irradiating than the CT-scan in the out-of-field region. • The EOS system may have an advantage by reducing effective doses in radio-sensitive organs.
Time projection chambers have been successfully refined for the use in particle physics experiments. The excellent imaging capability of MUNU and Gotthard experiments encouraged us to further improve ...this technique. Experimental details, detector performance, event identification, choice of gas, results and future developments of both experiments are discussed.
We present some important results related to Micromegas-TPC development for rare event detection: First, we show the influence of the detection plane structure on the energy resolution, where, ...replacing the wires planes (MWPC) by the Micromegas micropattern, gave a high collection efficiency with good uniformity and good energy resolution. Second, we prove that the increase of the height of the amplification zone permits a good charge collection at higher gas pressure. Third, we present a new gas mixture Xe(98)CF4(2) , which is convenient for the search of neutrinoless double beta decay in 136Xe. Fourth, large size Micromegas, with 50 cm of diameter is operated in the Gotthard-TPC (200 l) and showed high effciency and good energy resolution with low energy sources.
Mobility of thorium ions in liquid xenon Wamba, K.; Hall, C.; Breidenbach, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2005, Letnik:
555, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We present a measurement of the
226
Th ion mobility in LXe at 163.0
K and 0.9
bar. The result obtained, 0.240
±
0.011 (stat)
±
0.011 (syst) cm
2
/(kV-s), is compared with a popular model of ion ...transport.
A linear RFQ ion trap for the Enriched Xenon Observatory Flatt, B.; Green, M.; Wodin, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2007, Letnik:
578, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The design, construction, and performance of a linear radio-frequency ion trap (RFQ) intended for use in the Enriched Xenon Observatory (EXO) are described. EXO aims to detect the neutrinoless ...double-beta decay of
136Xe to
136Ba. To suppress possible backgrounds EXO will complement the measurement of decay energy and, to some extent, topology of candidate events in a Xe filled detector with the identification of the daughter nucleus (
136Ba). The ion trap described here is capable of accepting, cooling, and confining individual Ba ions extracted from the site of the candidate double-beta decay event. A single trapped ion can then be identified, with a large signal-to-noise ratio, via laser spectroscopy.
A liquid xenon ionization chamber in an all-fluoropolymer vessel LePort, F.; Pocar, A.; Bartoszek, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2007, Letnik:
578, Številka:
2
Journal Article
Recenzirano
Odprti dostop
A novel technique has been developed to build vessels for liquid xenon ionization detectors entirely out of an ultra-clean fluoropolymer. One such detector was operated inside a welded, He leak ...tight, all-fluoropolymer chamber. The measured energy resolution for 570
keV gamma rays is
σ
/
E
=
5.1
%
at a drift field of 1.5
kV/cm, in line with the best values obtained for ionization only detectors run in LXe using conventional, metal vessels.
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