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van Amelrooij E, van de Giesen N, Plomp J, Thijs M, Fico T. BLOSM: Boron-based large-scale observation of soil moisture: First laboratory results of a cost-efficient neutron detector. HARDWAREX 2022; 12:e00342. [PMID: 35942180 PMCID: PMC9356203 DOI: 10.1016/j.ohx.2022.e00342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A newly developed Boron-based Large-scale Observation of Soil Moisture (or BLOSM) system is currently being tested and implemented. The stationary system provides a cost-effective way to measure fast and thermalized neutrons by using low-cost, non-hazardous and accessible materials and equipment. BLOSM operates by measuring cosmic-ray induced neutrons and by comparing the amount of fast neutrons with the amount of thermal neutrons. Fast neutrons are moderated by hydrogen atoms in the air, organic materials, and especially and primarily by water in the soil, causing the ratio between fast and thermal to be a strong indicator of soil moisture content. The fast/thermal ratio is representative for soil moisture a scale of about 30 hectares, while standard soil moisture measurements are representative for less than a square meter. This is a well-established fact but present neutron detectors are very costly. Thanks to the low-cost of the probe, BLOSM can eventually be applied at a large scale and significantly increase the number of soil-water data points thereby enabling improvement of existing hydrology models as well as new applications such as monitoring fire hazards and agricultural droughts. Here, we present the build and first tests in the laboratory. We show that BLOSM can indeed measure fast and thermal neutrons, which opens the way to applications outside the laboratory.
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Affiliation(s)
- Edward van Amelrooij
- Department of Water Management, Faculty of Civil Engineering & Geosciences, Delft University of Technology, 2628 CN Delft, The Netherlands
| | - Nick van de Giesen
- Department of Water Management, Faculty of Civil Engineering & Geosciences, Delft University of Technology, 2628 CN Delft, The Netherlands
| | - Jeroen Plomp
- Reactor Institute Delft, Delft University of Technology, 2628 CN Delft, The Netherlands
| | - Michel Thijs
- Reactor Institute Delft, Delft University of Technology, 2628 CN Delft, The Netherlands
| | - Tomáš Fico
- MicroStep-MIS, spol. s r.o., 831 04 Bratislava, Slovakia
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Milián-Sánchez V, Scholkmann F, Fernández de Córdoba P, Mocholí-Salcedo A, Mocholí F, Iglesias-Martínez ME, Castro-Palacio JC, Kolombet VA, Panchelyuga VA, Verdú G. Fluctuations in measured radioactive decay rates inside a modified Faraday cage: Correlations with space weather. Sci Rep 2020; 10:8525. [PMID: 32444614 PMCID: PMC7244597 DOI: 10.1038/s41598-020-64497-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/13/2020] [Indexed: 11/29/2022] Open
Abstract
For several years, reports have been published about fluctuations in measured radioactive decay time-series and in some instances linked to astrophysical as well as classical environmental influences. Anomalous behaviors of radioactive decay measurement and measurement of capacitance inside and outside a modified Faraday cage were documented by our group in previous work. In the present report, we present an in-depth analysis of our measurement with regard to possible correlations with space weather, i.e. the geomagnetic activity (GMA) and cosmic-ray activity (CRA). Our analysis revealed that the decay and capacitance time-series are statistically significantly correlated with GMA and CRA when specific conditions are met. The conditions are explained in detail and an outlook is given on how to further investigate this important finding. Our discovery is relevant for all researchers investigating radioactive decay measurements since they point out that the space weather condition during the measurement is relevant for partially explaining the observed variability.
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Affiliation(s)
- V Milián-Sánchez
- Institute for Industrial, Radiophysical and Environmental Safety, Universitat Politècnica de València, Camino de Vera, s/n, 46022, València, Spain
| | - F Scholkmann
- Research Office for Complex Physical and Biological Systems, 8006, Zurich, Switzerland.
| | - P Fernández de Córdoba
- Grupo de Modelización Interdisciplinar, InterTech, Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, Camino de Vera, s/n, 46022, València, Spain
| | - A Mocholí-Salcedo
- Traffic Control Systems Group, ITACA Institute, Universitat Politècnica de València, Camino de Vera, s/n, 46022, València, Spain
| | - F Mocholí
- Traffic Control Systems Group, ITACA Institute, Universitat Politècnica de València, Camino de Vera, s/n, 46022, València, Spain
| | - M E Iglesias-Martínez
- Grupo de Modelización Interdisciplinar, InterTech, Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, Camino de Vera, s/n, 46022, València, Spain
| | - J C Castro-Palacio
- Grupo de Modelización Interdisciplinar, InterTech, Instituto Universitario de Matemática Pura y Aplicada, Universitat Politècnica de València, Camino de Vera, s/n, 46022, València, Spain
| | - V A Kolombet
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Science, Moscow Region, Pushchino, 142290, Russia
| | - V A Panchelyuga
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Science, Moscow Region, Pushchino, 142290, Russia
| | - G Verdú
- Institute for Industrial, Radiophysical and Environmental Safety, Universitat Politècnica de València, Camino de Vera, s/n, 46022, València, Spain
- Chemical and Nuclear Engineering Department, Universitat Politécnica de València, Camino de Vera, s/n, 46022, València, Spain
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Woolf RS, Sinclair LE, Van Brabant RA, Harvey BJA, Phlips BF, Hutcheson AL, Jackson EG. Measurement of secondary cosmic-ray neutrons near the geomagnetic North Pole. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 198:189-199. [PMID: 30640033 DOI: 10.1016/j.jenvrad.2019.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 12/27/2018] [Accepted: 01/02/2019] [Indexed: 06/09/2023]
Abstract
The spectrum of cosmogenic neutrons at Earth's surface covers a wide energy range, from thermal to several GeV. The flux of secondary neutrons varies with latitude, elevation, solar activity, and nearby material, including ground moisture. We report the results from a campaign to measure count rates in neutron detectors responding to three different energy ranges conducted near the geomagnetic North Pole at CFS Alert, Nunavut, Canada (82.5°N, 62.5°W; vertical geomagnetic cutoff rigidity, RC = 0 GV) in June of 2016. In November 2016, we performed a follow-on measurement campaign in southern Canada at similar RC (1.5 GV) and elevations. We conducted these measurements, at varying elevation and ground moisture content, with unmoderated and moderated 3He detectors for thermal and epithermal-to-MeV sensitivity, and with EJ-299-33 pulse shape discrimination plastic scintillator detectors for fast neutrons. Background gamma rays were monitored with NaI(Tl) detectors. Using these data sets, we compared the measured count rates to a predictive model. This is the first ever data set taken from this location on Earth. We find that for the thermal and epithermal-to-MeV neutron measurements the predictive model and data are in good agreement, except at one location on rock-covered ground near 1 km elevation. The discrepancy at that location may be attributable to ground moisture variability. Other measurements, during this campaign and prior, support the assertion that ground moisture plays a critical role in determining neutron flux.
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Affiliation(s)
- Richard S Woolf
- Space Science Division, U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
| | - Laurel E Sinclair
- Natural Resources Canada, Government of Canada, 930 Carling Ave (CEF, Bldg 7, Observatory Cr.), Ottawa, Ontario, K1A 0Y3, Canada.
| | - Reid A Van Brabant
- Natural Resources Canada, Government of Canada, 930 Carling Ave (CEF, Bldg 7, Observatory Cr.), Ottawa, Ontario, K1A 0Y3, Canada.
| | - Bradley J A Harvey
- Natural Resources Canada, Government of Canada, 930 Carling Ave (CEF, Bldg 7, Observatory Cr.), Ottawa, Ontario, K1A 0Y3, Canada.
| | - Bernard F Phlips
- Space Science Division, U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
| | - Anthony L Hutcheson
- Space Science Division, U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
| | - Emily G Jackson
- Formerly: NRC Research Associate Resident at the U. S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA.
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Hutcheson AL, Grove JE, Mitchell LJ, Phlips BF, Woolf RS, Wulf EA. Effects of rain and soil moisture on background neutron measurements with the SuperMISTI neutron array. RADIAT MEAS 2017. [DOI: 10.1016/j.radmeas.2017.03.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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