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Measurements of natural radioactivity in European underground labs within the ILIAS project. Jan Kisiel Institute of Physics, University of Silesia, Katowice, Poland (kisielj@us.edu.pl). ILIAS (http://ilias.in2p3.fr/ilias_site/ilias.htm).
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Measurements of natural radioactivity in European underground labs within the ILIAS project Jan Kisiel Institute of Physics, University of Silesia, Katowice, Poland (kisielj@us.edu.pl) Warszawa, July 3rd 2006
ILIAS (http://ilias.in2p3.fr/ilias_site/ilias.htm) • „is an Integrated Infrastructure Initiative that has pulled together all of Europe’s leading infrastructures in Astroparticle Physics” • „results from a consultation of the community and an internal reviwe process throught ApPEC” • 20 participants + many non contactor institutions • Three scientific poles: - Physics in deep Underground laboratories (Gran Sasso, Modane, Canfranc and Boulby) 1 Transnational access activity 3 Networking activities (Deep Underground Science Laboratories, Direct dark matter detection, Search on double beta decay) 2 Joint research activities (Low Background Techniques for Deep Underground Science, Integrated double-beta-decay European Activities) - Gravitational wave detection - Theoretical astroparticle physics Warszawa, July 3rd 2006
What have been done? • Gran Sasso Lab. (December 2004): in-situ measurements, radon emission from the surface, water samples measurements, • Boulby Lab. (August 2005): in-situ measurements, radon emission from the surface, rock samples measurements, • Sieroszowice/Poland, salt chamber: in-situ measurements, radon emission from the surface, rock samples measurements. Warszawa, July 3rd 2006
6-17.12. 2004 r. Warszawa, July 3rd 2006
LNGS measurements, Dec’2004 – cont. 222Rn concentration in the water Liquid scintilator method (measured with Wallac 1414 WinSpectral liquid sintillation Counter, in Katowice), 12 measurements – see map) Samples 1-10, 2-9, … were taken in the same place with slightly different methods (radan mobility!) – results are consistent Warszawa, July 3rd 2006
LNGS, Dec’2004: map of water samples measurements Warszawa, July 3rd 2006
LNGS measurements, Dec’2004 – cont. 222Rn concentration in the air Pico-Rad method (Insta-Fluor scinitilator, activate carbon, 48h exposure, 12 mesurements in Halls A, B and C) Warszawa, July 3rd 2006
In situ measurements: • HPGe detector (EG&G ORTEC): - 30% relative efficiency, - crystal length 59mm and diameter 58.6mm, - resolution: 0.67keV at 122keV and 1.73keV at 1.33MeV • M-1 B32 (ORTEC) software for the determination of radioisotope activity • M-1 geometry: detector mounted 1m above the surface, gamma emitters recorded from the area in a radius of 10m to a depth of about 30cm (depending on ground and photon enregy) Warszawa, July 3rd 2006
Sieroszowice: KGHM copper mine with large (15x15x100m) salt coverns at about 1000m underground – possible location of an underground low background laboratory in Poland Warszawa, July 3rd 2006
Net Count Rate [cps] – in situ mesurements Warszawa, July 3rd 2006
In situ measurements: GS, Boulby, Sieroszowice Integral background counting rates Warszawa, July 3rd 2006
In situ measurements: GS, Boubly and Sieroszowice Warszawa, July 3rd 2006
Radon 222Rn measurements in Boulby: • Durridge RAD7 detector has been used in its sniff mode: - looks at the 6MeV alpha particles from the 218Po decay, - variations of radon emission has been monitored by using 48-hours protocol, 1 hour intervals, - checks of „internal humidity” (detector works correctly if internal humidity < 10%) - mesurements in 4 points: 3 in JIF area + 1 in H area. Warszawa, July 3rd 2006
Radon measurements: Boulby 2005 Warszawa, July 3rd 2006
Radon measurements in Boulby: results • Mean (from 48 hours measurement) values: - H area: 2.3±1.7Bq/m3 - JIF area 1 (Box2): 2.5±1.4Bq/m3 - JIF area 2 (transport hall): 4.2±1.9Bq/m3 - JIF area 3 (main lab): 2.5±1.9Bq/m3 • Conclusions: - mean values are „practically” the same Warszawa, July 3rd 2006
Future plans (2006): • 2 in-situ measurements in 2006 (Modane, Boulby and Canfranc): - use two (not one!) portable detectors, - HPGe detector (EG&G ORTEC) the „old” one, - GX3020 (Canberra Industries): possibility of measurements in different geometries!, with the minimum detectable activity about 0.1Bq/kg, - radon emission measurements, - rock and/or water samples measurements Warszawa, July 3rd 2006