A multichannel position sensitive ionization chamber for X-ray intensity monitoring

Abstract A multichannel position sensitive ionization chamber with low noise electronics has been built for intensity monitoring of two barely separated beams in dual energy subtraction angiography. The chamber construction and performance measured with an X-ray source are presented. Poisson statistics of the absorbed photons is compared with the intensity resolution and found to be the principal limit. The spatial resolution and the noise in a given integration times are discussed.