PADC plastic Solid State Track Detector
WIDE RANGE NEUPIT - "WNP" - is the excellent personal neutron dosemeter presented by CHIYODA TECHNOL CORPORATION, and is the solid state track detector (SSTD) using poly allyl di-glycol carbonate(PADC) plastic as the detector of charged particles.
WNP is already covered the all of our personal neutron monitoring services, over 20,000 dosemeters are issued every month enclosed in glass badge.
FEATURES of WNP
1) Wide energy range neutron monitor
WNP is the dosemeter that enables to measure wide energy range neutron, from thermal neutron to fast neutron, - 0.025eV to 15MeV -, are measurable continuously.
WNP is basically two elements type detector that has two kinds of materials as the radiator of charged particles by interaction with incident neutron. One is boron nitrate(BN) sheet for measuring thermal and low energy region neutron, the other is polyethylene sheet for measuring fast neutron.
The α particle from BN by (n,α) reaction with neutron and recoil proton from polyethylene are mainly contribute to etch pit generation.
BN sheet, polyethylene sheet and PADC plastic are packaged by heat-shrinking tubing to contact tightly.
2) excellent energy characteristic
To optimize WNP energy responses, neutron sensitivity of each radiator are adjusted by change the thickness and or diameters of etch pit to be count.
These adjustments by experimental and Monte Carlo simulation data, reasonable energy characteristic is obtained resultantly.
3) Short time chemical etching and round shape etch pit
Short time chemical etching method in high temperature is introduced to our PADC plastic treatment. To add pre-soaking treatment to etching, round shape etch pits are obtained.
The round shape etch pit makes counting efficiency so stable. The combination of high temperature treatment and pre-soaking makes it possible.
4) Automatic and high speed counting system
The all of etch pit in position to each radiator are counted automatically by image analyzing system with automatic microscope.
The image analyzing system with auto-focus and auto-staged microscope is measurable 110 pieces of PADC plastic detector at once.
24mm2 area of each radiator position are scanned in a one minuet.