I show how air, thin tissue paper, copier paper, and mylar plastic provide varying levels of shielding against the alpha particles emitted by a Polonium-210 sample.
Aare Baumer - 2020-03-14
Hello Sean, nice to see your experiment. But why you are using Polonium? Years ago I had article in Amateur scientist about my interactive exhibit and I used Am241 from smoke detector and CCD camera.
kd5byb - 2020-03-15
I was thinking the same - why not Am241? Still, very nice demonstration of how alphas are shielded by air and other materials. :)
Sean Breheny - 2020-03-15
I used Polonium because it is a pure alpha emitter which decays to a stable isotope. If I used Am241, there would be some gamma output and it would not be so easy to show that the paper stopped almost all the alpha (because the gamma would still be reaching the detector)
Aare Baumer - 2020-03-15
@Sean Breheny Aha, got it.
kd5byb - 2020-03-15
@Sean Breheny Ah ha! That makes excellent sense. :)
Aare Baumer - 2020-03-15
@kd5byb Then disaining exhibit about radioactivity, I didnt know about gamma rays! But I was hit by surprise, that CCD matrix was knocked down pixel by pixel(p-n sandwich was destroyed). It took 4-5 months of direct 24 h. bombing until CCD was out. Distance between Am241 and matrix was 3 mm.
Aare Baumer - 2020-03-14
Hello Sean, nice to see your experiment. But why you are using Polonium? Years ago I had article in Amateur scientist about my interactive exhibit and I used Am241 from smoke detector and CCD camera.
kd5byb - 2020-03-15
I was thinking the same - why not Am241? Still, very nice demonstration of how alphas are shielded by air and other materials. :)
Sean Breheny - 2020-03-15
I used Polonium because it is a pure alpha emitter which decays to a stable isotope. If I used Am241, there would be some gamma output and it would not be so easy to show that the paper stopped almost all the alpha (because the gamma would still be reaching the detector)
Aare Baumer - 2020-03-15
@Sean Breheny Aha, got it.
kd5byb - 2020-03-15
@Sean Breheny Ah ha! That makes excellent sense. :)
Aare Baumer - 2020-03-15
@kd5byb Then disaining exhibit about radioactivity, I didnt know about gamma rays! But I was hit by surprise, that CCD matrix was knocked down pixel by pixel(p-n sandwich was destroyed). It took 4-5 months of direct 24 h. bombing until CCD was out. Distance between Am241 and matrix was 3 mm.