Abstract：In the low-energy X-ray reference radiation field of China Institute of Metrology, a tungsten target molybdenum filter X-ray radiation with a tube voltage of 23, 25, 28, 30, 35kV was established, and the additional filtration was 0.06mm Mo film. Its half-value layer measurement shows that the half-value layer is maintained at 0.346 to 0.405mm of aluminum. The effective energy is maintained at 15.4 to 16.4keV, which is significantly higher than the molybdenum target X-rays excited by the same tube voltage. The correction factor of the mammography X-ray free air ionization chamber was measured, and the measurement of the air kerma was completed.
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2018, Vol. 39 
