Study on correction factor of synchrotron radiation X-ray free air ionization chamber composite loss

At the 4W1B test station of the Synchrotron Radiation Source in Beijing, the composite loss correction factor of the free-radiation ionization chamber of the synchrotron radiation was measured by the 12KeV single-energy X-ray obtained from the twin crystal. The corresponding free air ionization chamber and the traditional method for measuring the composite loss correction factor are introduced. Under the condition of voltage saturation, the method of changing the thickness of the absorption sheet is used to change the dose rate and calculate the composite loss correction factor. The result is shown in The corrected share of the selected 2400V operating voltage is 1.000000048.