Testing the absolute beam intensity of the high-energy pulsed electron beam with a double-mode readout ionization chamber

We constructed an ionization chamber (IC) to test the absolute intensity of the BEPC-LINAC (Beijing Electron Positron Collider-Linear Accelerator) test beam. The IC was adapted for the 1.89 GeV high-energy electron beam, with pulse time width of 1.2 ns and frequency of 25 Hz, by equipping it with a double-mode readout and choosing the optimum circuit parameters for the readout modes. The measured absolute intensity of the test beam is 7.2×109 electron/s, and is consistent with PSPICE simulations.