Figure 3
From: First evaluation of a novel ionisation chamber for thermal neutron beam monitoring
Schematic representation of the 
readout concept. The symmetric parallel plate ionisation chamber pair on the left is fed with a biasing voltage on its central electrode. One of the chambers is boron coated. γ-induced signals together with noise are annihilated while the neutron signal is read out by a noise-optimised TIA, limited in bandwidth to about 125 kHz. In the final design the bandwidth is actually limited to 50 kHz, precisely the bandwidth needed to detect a Gaussian pulse of 10μs FWHM