Thank you about the information! I will start immediatly trying to find some information about boron. But if it does not work I will think about rebuilding the circuit.
I need urgent help! we have a beam made of some neutrons and some photons. I thought about the beryllium polycrystaline but I'm not really sure it could work. The beam has an energy of 2 MeV moreless. Sorry for my spoken english.