PR157 Characterization of particle detectors and dosemeters used at flight altitudes and on space missions

Transcription

1 PR157 Characterization of particle detectors and dosemeters used at flight altitudes and on space missions PR145 (which was granted beam) may be annihilated as the work now forms part of PR157

2 Günther Reitz, Thomas Berger Deutsches Zentrum für Luft- und Raumfahrt (DLR), Germany Frank Wissmann, Thomas Möller, Ralf Nolte Physikalisch-Technische Bundesansalt (PTB), Germany Soenke Burmeister Christian Albrechts University of Kiel, Germany Les Bennett, Brent Lewis Royal Military College of Canada (RMC), Canada Ken Garrow Bubble Technologies, Inc. (BTI), Canada Ricky Smit, Zinhle Buthelezi ithemba Laboratories (TLABS), South Africa Andy Buffler, Rudolph Nchodu University of Cape Town (UCT), South Africa 2

3 Space Radiation Environment... the most complex natural radiation field galactic cosmic rays (protons, helium, up to iron with high energies) solar particle events trapped radiation (in the Earth s magnetic field Van Allen Belts) 3

4 Space Radiation Environment interaction of the primary radiation field with materials (spacecraft, planetary surface) leads to a secondary radiation field including a high contribution of neutrons in a wide energy range. Total dose equivalent values : up to a few hundred µsv/day (ISS) 4

5 Objectives of PR156 Radiation detector systems for use in space need to be calibrated in radiation fields simulating the space radiation environment heavy ion accelerators (NIRS, Brookhaven, GSI, ) neutron beam facilities at low and high energies (PTB and ithemba LABS) the present project is concerned with the experimental characterization of nine different instruments which have been designed for the investigation of neutron energy distributions in extreme environments. 5

6 Detector Systems: MATROSHKA MATROSHKA experiment onboard the ISS anthropomorphic phantom with a range of passive and active detectors 6

7 Detector Systems: MATROSHKA silicon scintillator devices designed to separately measure the dose of charged and neutral radiation in a tissue equivalent BC430-scintillator at different positions inside the MATROSHKA phantom. Outer Dimension: 24 x 28 x 44 mm³ 7

8 Detector Systems: IRAS IRAS (Ionizing Radiation Sensor) ExoMars Mission to Mars lightweight particle spectrometer designed to characterize the radiation environment on the Mars surface. measures dose and dose equivalent rates for neutral and charged particles separately. the detector is based on a silicon telescope technology, enabling neutron and charged particle discrimination. 8

9 Detector Systems: IRAS IRAS (Ionizing Radiation Sensor) ExoMars Mission to Mars first results from calibration at ithemba LABS 2007 energy deposition for charged particles and neutrons in the different silicon detectors of the IRAS prototype Note: for the run in 2009 the real flight telescope will be applied 9

10 Detector Systems: RAD RAD (Radiation Assessment Detector) MSL Mission to Mars (NASA) solid state detector telescope and CsI calorimeter with active coincidence logic to identify charged particles. separate scintillators with anti-coincidence logic to detect neutrons and gamma rays. 10

11 Detector Systems: RAD RAD (Radiation Assessment Detector) MSL Mission to Mars Results from 2007 run at ithemba measured energy deposition by 100 MeV neutrons at the ithemba facility for the different RAD neutron channels, compared to a GEANT4 Monte Carlo simulation (in black) Further calibrations for energies up to 100 MeV are needed 11

12 Detector Systems: CHENSS Canadian High-Energy Neutron Spectrometry System 20 cm gelled organic scintillator three gain settings provide desired dynamic range (1 200 MeV) battery powered, stand-alone system designed for autonomous operation on the space shuttle 12

13 Detector Systems: CHENSS Preliminary CHENSS results from 2007 run at ithemba LABS 100 MeV data unfolded for CHENSS peak observed at ~97 MeV (as expected) Quantitative fluence verification (in progress) TLABS measurements Monte Carlo simulations 0 degrees 16 degrees 0 degrees 13

14 Problem: Complex Radiation Field Galactic Cosmic Radiation Dose rate at 10 km: 5 µsv/h µ (5%), n(45%), γ+e(35%), p(15%) PTB ithemba ~100 MeV ~1 MeV 14

15 Solution: PTB Flight Case TEPC: measures equivalent dose in complex fields compact system incl. own data acquisition optimized for in-flight measurements incl. particle discrimination optimized for permanent measurements Reference instrument Flight Case Tissue equivalent proportional counter (microdosimetry) TEPC CACS Results from 263 flights 15

16 New developments: RAMONA RAMONA Radiation Monitoring Onboard Aircraft Collaboration between German Aerospace Centre (DLR), Univ. Kiel (CAU), Univ. Braunschweig (TUBS), Lufthansa (DLH), LTU and PTB Really compact dosemeters NAVIDOS, Liulin, AMIRA for permanent installation on board aircraft 16

17 Summary the present project brings to ithemba a collection of 9 instruments which are the state-of-the-art in radiation detection and monitoring at high altitudes and in space. ithemba LABS is the only facility where the response of the instruments to high energy neutrons may be measured. these characterizations have been completed at < 20 MeV at PTB, and at 100 MeV and 200 MeV at ithemba in

18 Beam time request ns-pulsed neutron beams no additional costs to itl use existing D-line infrastructure Request made for 2 weekends Weekend 1: E p = 66 MeV Weekend 2: E p = 100 MeV 18

19 additional slides in reserve for questions 19

20 TLABS/UCT/CHENNS Collaboration Suggestions for possible CHENNS projects: Experimental calibrations & analysis of CHENSS runs at TLABS GEANT or MCNPX modelling of CHENSS response 20

21 TEPC in Neutron Fields Results from previous measurements: DOSMAX PTB (TEPC) IRSN (TEPC) SSI (TEPC) 21

22 Collaborative presentations based on TLABS work K. Garrow, B.J. Lewis, L.G.I. Bennett, M. Smith, H. Ing, R. Nolte, S. Rottger, R. Smit, R. Bradley and L. Tomi, Update on Calibration Studies of the Canadian High Energy Neutron Spectroscopy System (CHENSS), Meeting of the International Space Station Multilateral Radiation Health Working Group, Dubna, Russia, Oct B.J. Lewis, L.G.I. Bennett, S-H Byun, J. Chen, T. Conroy, J.Dubeau, H. Ing, K. Garrow, R. Surrette, T. Waker, R. Nolte, S. Rottger, R. Smit, A. Buffler, L. Tomi, CSA Discipline Working Group (DWG): Metrology, International Space Station Multilateral Radiation Health Working Group, JSC-NASA, Houston, Texas, 4-7 Nov

23 A selection of recently published work Measurement of neutron energy spectra from MeV using stacked liquid scintillators A. Buffler, F.D. Brooks, M.S. Allie, P.J. Binns, V. Dangendorf, K.M. Langen, R. Nolte and H. Schuhmacher, Nuclear Instruments and Methods A 476 (2002) High energy neutron reference fields for the calibration of detectors used in neutron spectrometry R. Nolte, M.S. Allie, P.J. Binns, F.D. Brooks, A. Buffler, V. Dangendorf, J.P. Meulders, H. Schuhmacher, B. Wiegel, Nuclear Instruments and Methods A 476 (2002) Cross section measurements for neutron-induced reactions in copper at neutron energies of 70.7 and MeV. J. M. Sisterson, F.D. Brooks, A. Buffler, M.S. Allie, D.T.L. Jones and M.B. Chadwick, Nuclear Instruments and Methods B 240/3 (2005) RBE of 200 MeV neutron radiation for the induction of chromosodal aberration in human lymphocytes R. Nolte, V. Dangendorf, A. Buffler, F.D. Brooks, J.P. Slabbert, F.D. Smit, M. Haney, E. Schmid, G. Stephan In proceedings of International Workshop on Fast Neutron Detectors and Applications (Cape Town, 2-6 April 2006) Proceedings of Science (FNDA2006) 082 Cross sections for neutron-induced fission of 235U, 238U, 209Bi and natpb in the range from 33 to 200 MeV measured relative to n-p scattering R. Nolte, M.S. Allie, F.D. Brooks, A. Buffler, V. Dangendorf, J.P. Meulders, H. Schuhmacher, F.D. Smit and M. Weierganz Nuclear Science and Engineering 156 (2007) A compact high-energy neutron spectrometer F.D. Brooks, A. Buffler, M.S. Allie, M.S. Herbert, F.D. Smit, R. Nolte, V. Dangendorf, Radiation Protection Dosimetry 126 (2007) Determination of neutron energy spectra inside a water phantom irradiated by 64 MeV neutrons M. S. Herbert, F. D. Brooks, M. S. Allie, A. Buffler, M. R. Nchodu, S. A. Makupula, D. T. L. Jones, and K. M. Langen Rad Prot Dos 126 (2007)