Radiation maps

• 1) Simplified radiation maps to be used to identify equipment exposed to radiation condition(s) above the alert radiation thresholds

To determine if their equipment will be exposed to radiation conditions above or below the alert thresholds, the ITER systems need the following simplified radiation maps (contour plots per decade):

• Maps of radiation condition producing accumulated ionization damages:

Total Ionizing Dose rate (Gray/s) induced by photons plus neutrons (full energy ranges) in Si (not SiO2) during operation;

Total Ionizing Dose rate (Gray/s) induced by photons plus neutrons (full energy ranges) in Si (not SiO2) during cask transfer;

• Maps of radiation condition producing atomic displacement damages:

Neutron flux (1 MeV Si - equivalent (not SiO2 equivalent) neutron.cm2.s-1) during operation;

Neutron flux (1 MeV Si - equivalent (not SiO2 equivalent) neutron.cm2.s-1) during cask transfer;

• Maps of radiation condition producing SEE/SEU:

Flat neutron flux (neutron.cm2.s-1 summed over the full energy range: 0 eV to 20 MeV) during operation;

Flat neutron flux (neutron.cm2.s-1 summed over the full energy range: 0 eV to 20 MeV) during cask transfer.

Simplified radiation maps will be appended to radiation simulation reports which describe the geometric model and radiation source(s) used to calculate radiation data and which summarizes the calculated radiation data.

See Minutes of meeting dedicated to RHA-CM action-08 (simplified radiation maps) (10-Sep-2013) (KQXDLS).

• 2) Detailed radiation maps to design radiation shielding and to define radiation tests

To calculate local shielding and to perform radiation tests, the ITER systems need the following detailed radiation maps:

• Maps of radiation condition producing accumulated ionization damages:

Total Ionizing Dose rate (Gray/s) induced by photons and neutrons (full energy ranges) in Si (not SiO2) during operation;

Total Ionizing Dose rate (Gray/s) induced by photons and neutrons (full energy ranges) in Si (not SiO2) during cask transfer;

• Maps of radiation condition producing atomic displacement damages:

Neutron flux (1 MeV Si - equivalent (not SiO2 equivalent) neutron.cm2.s-1) during operation;

Neutron flux (1 MeV Si - equivalent (not SiO2 equivalent) neutron.cm2.s-1) during cask transfer;

• Maps of radiation condition producing SEE/SEU:

Thermal neutrons:

• neutron flux (neutron.cm2.s-1 summed over the energy range 0 eV to 100 keV) during operation;
• neutron flux (neutron.cm2.s-1 summed over the energy range 0 eV to 100 keV) during cask transfer;

“Medium” energy neutrons:

• neutron flux (neutron.cm2.s-1 summed over the energy range 100 keV to 10 MeV) during operation;
• neutron flux (neutron.cm2.s-1 summed over the energy range 100 keV to 10 MeV) during cask transfer;

“High” energy neutrons:

• neutron flux (neutron.cm2.s-1 summed over the energy range 10 MeV to 20 MeV) during operation;
• neutron flux (neutron.cm2.s-1 summed over the energy range 10 MeV to 20 MeV) during cask transfer;

Instructions for opening detailed radiation maps are provided in the document 01 - Radiation maps (KGEW3D).

PCRs taken into account for the 2013 revision of the radiation maps:

• Final Report DCR-127 "Changes to Tokamak Complex Layout & Magnetic / Electrical Properties of Structural Elements" (2E923N)
• PCR-416: https://user.iter.org/?uid=76BU3G
• PCR-416 CWS Shielding Study (9K8Q6D)
• PCR-416 CWS Shielding Implementation - Interim Report (BS6QM6)