There are many sorts of radiation. One distinction is ionizing
vs non-ionizing. A Geiger-Muller gas tube detects ionizing
radiation (electron, proton, heavy ion, gamma, X-ray) but
ignores neutrons (these need special media to convert to
some other more detectable energetic species).
Any PN junction is an ionizing radiation detector. The issue
is sensitivity (real and false) all down the line, from the
self-capacitance and conversion efficiency at the front
end, to signal chain noise and gain and pulse shaping /
extinction.
There are many, many, many papers published by CERN
and affiliated science-funding-ticks about radiation detector
circuits and sensors. You can also find dosimeters using
charge accumulation (detect and integrate) and event-
counting methods if you dig deep.