2πα、2πβ粒子发射率现场校准装置的建立

The Establishment of the On-site Calibration Device for 2πα and 2πβ Particle Emission Rate Measurement

基于大面积无窗流气正比计数器和多道能谱测量单元,建立了2πα、2πβ粒子发射率现场校准装置。性能测试结果表明:该装置对α平面源的坪区为700~1 500 V,坪长为800 V,坪斜为0.25%/100 V;对β平面源的坪区为1 650~2 050 V,坪长为400 V,坪斜为0.44%/100 V。使用该装置测量2πα、2πβ粒子发射率基准装置定值的标准平面源,经各项修正后,结果与基准测量结果在不确定度范围内一致。在现场校准了一批α、β标准平面源,校准结果与上一校准周期的结果在不确定度范围内一致,验证了该装置作为现场测量标准装置实现粒子发射率量值现场传递的可行性。

Based on a large-area, windowless, gas-flow proportional counter, an alpha/beta 2 π emission rate on-site calibration device is established. Performance tests are taken and the results show that the plateau of alpha lasts from 700 V to 1 500 V, the length is up to 800 V and the slope is 0. 25% per 100 V, the plateau of beta lasts from 1 650 V to 2 050 V, the length is up to 400 V and the slope is 0. 44% per 100 V. This on-site calibration device is used to measure the standard surface sources which are calibrated by the the absolute alpha/beta 2 π emission rate measuring system, the results are well agreed with the standard values within the range of uncertainties. On-site measurement of another group of standard surface sources are taken, values of corrected results are agreed with the values calibrated in previous cycles within the range of uncertainties, which verifies the feasibility of this calibration device to deliver the on-site standard values.