29th Symposium on Fusion Technology (SOFT 2016)

P4.059 Radiation shielding design evaluation for detectors of ITER VUV Edge Imaging Spectrometers

8 Sep 2016, 14:20

1h 40m

Foyer 2A (2nd floor), 3A (3rd floor) (Prague Congress Centre)

Board: 59

Poster D. Diagnostics, Data Acquisition and Remote Participation P4 Poster session

Speaker

YoungHwa An (National Fusion Research Institute)

Description

The local shielding design for the detector of ITER VUV Edge Imaging Spectrometer is optimized based on the MCNP calculation using a local port cell model of ITER Upper Port #18. A back-illuminated CCD, the envisaged VUV detector for ITER VUV Edge Imaging Spectrometer will be installed at ITER Upper Port #18 port cell region, in which a harsh radiation environment is expected with neutron flux higher than 10⁵5 neutrons·cm^-2-2·s^-1-1 mainly originated from 14 MeV d-t neutrons as well as high gamma ray dose of several tens kGy from the plasma, activated materials and ¹⁶16N isotopes in water coolant. To evaluate radiation exposure to the detector, the local port cell model is developed as well as the boundary neutron and gamma ray source model based on MCNP result using C-Lite, which is expected to reduce both calculation time and statistical error. Since the radiation exposure to the back-illuminated CCD should be mitigated as much as possible to minimize the radiation damage to the detector as well as single event upset, local shielding design options for the VUV detector with various shapes, thicknesses, and material compositions are evaluated. In this paper, preliminary radiation assessment for ITER Upper Port #18 port cell region and the optimized shielding design for VUV detectors with estimated shielding factor will be presented.