Alpha source also emits gamma

 This is the alpha source. It is being detected through the sides of the GM tube. Since paper will stop alpha radiation, it can't be detecting alpha. The emission of an alpha particle leaves the nucleus in an excited energy state. It then loses energy by emitting gamma ray photons. I was interested in using the alpha source as another option for showing the inverse square law decay in gamma ray intensity with distance. As the photographs show, the range of readings is not really good enough. I was using the most sensitive setting and still only getting readings precise to 1sf.