-----Original Message----- From: [email protected] > Aluminum foil will stop beta radiation (and look how thin it is).
Sure - and stopping the electron produces bremsstrahlung - easily detected, and you seem to be underestimating the capability of detectors. > Fast electrons are not very penetrating which may go some way toward explaining why Rossi said that you could detect radiation in some places but not others, and he provided a hole for the detector where he thought some would be detected, but not too much. Many things Rossi has said indicate he is not skilled in radiation detection, and that may be why he chose Levi, who is an expert. > Nevertheless, only about 1% of fast electrons create x-rays, and many of these will have energy considerably less than the maximum. 1% is huge. Even inexpensive meters are sensitive enough to detect them at far less percentage. The CRT is a good example - they are not particularly high voltage to being with (35 kV) and all electrons are stopped, most by phosphors, but still the old CRTs produce X-rays in the one mR/h range which is 100 times more than good detectors can register. One of the reasons no one wants them anymore. Jones
