首页|New LMRI CIEMAT primary standard for Cs-137 air-kerma
New LMRI CIEMAT primary standard for Cs-137 air-kerma
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
NSTL
Elsevier
This paper presents the details and the characterization of two new graphite-walled cavity ionization chambers that will constitute the first Spanish national air-kerma standard for Cs-137. Physical constants and correction factors were determined according to the recent recommendations of the ICRU 90 report and the corresponding uncertainty budgets are presented. The effect of considering one conduction electron in graphite instead of two has been studied for the first time and an increase of 0.04 % in the stopping-power ratio graphite-to-air has been found for the LMRI Cs-137-spectrum. The ratios of photon mass energy-absorption coefficients of air and graphite were calculated from the three databases recommended in ICRU 90 report and the standard deviation of the three values was only 0.02 %. The validity of the Spencer-Attix theory has been studied in detail for both chambers. The standard uncertainty of the reference air-kerma will drop from 0.76 % to 0.30 %.
NSTL
Elsevier
