Nuclear applications at the Hellenic Centre for Marine Research (HCMR): Radioactivity in the marine environment Dr. Christos Tsabaris Institute of Oceanography Hellenic Centre of Marine Research
Motivation & Goals Radiological surveillance of the seas, estuaries and coastal zone using new innovative technologies of gammaray spectrometry 137 Cs input at North Aegean Sea from the Marmara/Black seas Pending new nuclear reactors constructions at the east Aegean Sea Use of radio-tracers for understanding the marine environmental processes HCMR contribution for the development of a network for surveillance and alarm applications (collaboration with the GSRT and IAEA) Systematic control of the 137 Cs input at the North Aegean Database upgrade of marine radioactivity data in the Aegean sea New technologies and methods for in-situ marine detectors for continuous monitoring of radioactivity
First applications RADAM System* POSEIDON ΙΙ: Marine radioactivity measurements in three buoys (Athos, Lesvos, Saronikos) 41.00 40.00 A 39.00 L 38.00 37.00 G 36.00 35.00 20.00 21.00 22.00 23.00 24.00 25.00 26.00 27.00 28.00 *Aakenes U.R., Radioactivity monitored from moored oceanographic buoys, Chemistry and Ecology 10:1-2 (1995) 61
Field measurements problems RADAM 10 0 10-1 cps 10-2 214 Bi 40 K 214 Pb 214 Bi & 208 Tl & 137 Cs 10-3 10-4 0 500 1000 1500 2000 E γ [kev]
The idea of the ΚΑΤΕΡΙΝΑ detector Problems of RADAM operation: Instability of electronics, calibration using only two points ( 137 Cs & 40 Κ), low sensitivity (100 Bq/m 3 ), low spectroscopy (512 channels), limited operational depth of deployment (100m) Request of new technology and method for quantification of marine radioactivity in automatic and autonomous way in deep water masses ΚΑΤΕΡΙΝΑ: Innovative Sensors for Natural and Man-made Radioactivity Funds GSRT support through PRAXE project Implementation plans Design Electronics developments Mechanical developments Construction Calibrations Pressure Tests and control
The underwater spectrometer KATERINA INT.CL: G01T 7/00 Specifications Crystal: 3x3 NaI Consumption ~ 2.0 W (150mA) Resolution at 662keV: <6% Variable Εnergy Range Adjustable spectroscopy: max of 2048 channels Operating Temperature: 0-50 0 C. Correction for voltage drifts. Adjustable HV voltage Adjustable amplifier gain, PZC and shaping time. Autonomy (without PC connect) Option for Real Time (software independent)
Hardware Analog Nuclear Electronics (Pre-amplifier, Shaping Amplifier + Gain + Base Line Restoration + Pole Zero Cancellation + shaping time). Digital Electronics (Multichannel Analyzer + successive approximation ADC + RS232, USB and Ethernet Interface).
ΚΑΤΕΡΙΝΑ system Innovation Stability Continuous operation Improved sensitivity (30%) Calibration in the energy interval (50 3000 kev) Cost effective and low power consumption Operational depth 600m
Algorithm development/ automated analysis * Automated spectrum analysis using wavelets (Wavelet smoothing techniques) Energy calibration Peak detection Energy determination Radionuclide identification Count determination and automated background subtraction + System efficiency Automated process for quantitative analysis of the detected rdaionuclides * C. Tsabaris and A. Prospathopoulos, Automated quantitative analysis of in-situ NaI measured spectra in the marine environment using a wavelet-based smoothing technique, Applied Radiation & Isotopes 69 (2011) pp. 1546
Quantification Method: MC simulation using GEANT4 and MCNP5 c/s ΝaI E γ Taking into account the interactions of the gamma-rays in a) the water, b) the material of the housing and c) the NaI crystal. e - γ γ Water Interactions Compton scattering Photoelectric Pair production
Integration in POSEIDON network The system ΚΑΤΕΡΙΝΑ has full specs for its integration in the POSEIDON network and in international networks (e.g. GOOS) Monitoring Network for Marine Radioactivity Real-Time data transmission and surveillance of radioactivity levels Radioecology and nuclear safety Supporting national policies of the ocean understanding Monitoring potential dispersion of radionuldies in case of a radiological emergency
THE OCEAN OF TOMORROW FP7-OCEAN 2013 MESSENGERS Requested budget 5.8 M Coastal network in areas of future nuclear reactors constructions Pre-operational Baseline information MESSENGERS / POSEIDON
Project KATERINA at a glance Validation of operability from the International Atomic Energy Agency (ΙΑΕΑ 2005) Patent 12 papers in peer review international journal 21 presentations in int. conferences Commercialization Participation in 8 research programs (period of 2005-2015) Collaboration in IAEA projects (RER/7/003) System application from National Agencies
Application 1: Water Resources 10 6 10 5 214 Pb(351) 214 Bi(609) 214 Bi(1377) 214 Bi(1024) Study of the quantity and quality of submarine groundwater discharges (Springs) and water management. counts 10 4 214 Pb(295) 40 K(1461) 214 Bi(1764) 214 Bi(3 lines) Application area: Stoupa Messinia (2007-2010), Monaco, Adriatic Sea, Korfos, Chalkida 214 Bi(768) 214 Bi(2447) 10 3 214 Bi(1377) 208 Tl(2614) 10 2 500 1000 1500 2000 2500 E γ [kev]
Application 2: Study of submarine faults Correlation of radon variation with microseismicity and seismicity in submarine faults Field areas: L Aquila and Marmara Sea (ESONET project) 12/3/2015 NuPECC Workshop
Cont (ESONET Project)
Application 3: Radioprotection TENORM measurements in fertilizer industry, IAEA TC project
Gamma-ray spectra (Sediment-Water)
System Improvements Software for automated analysis in combination with alarm applications Installing the system in multiple stationary and mobile platforms to cover spatially large areas for mapping Upgrade for depths up 6000m To have a marine detection in-situ system for geophysical, oceanographical, energy exploration and radioprotection applications (Warning/ Alarm)
Thank you for your attention!!! 12/3/2015 NuPECC Workshop