Does thorium-232 emit X-rays?

Question

The question is derived from an experiment... "Red" tungsten TIG welding electrodes consists 2% of thorium-232. They are slightly radioactive... I have such electrodes, so I checked their radioactivity by an NR-750 Geiger counter (indeed they are radioactive).

I interpreted that particles, which are detected, are electrons from beta decay. But if I put electrodes behind a few mm steel shield, I still detect some events. Why? Does it mean that X-rays are also emitted? But why?

According to Thorium series, only alpha particles and beta particles are emitted.

Is there a control? What is the result of removing the welding electrodes, but keeping the steel shield (there could be contaminants in the steel)? What about the background radiation (with enough events to be statistically meaningful)? — Peter Mortensen, Apr 24 '22 at 09:07
Metal shield doesn't radiate itself in this experiment. Radiation is function of electrodes. — Andrew123, Apr 24 '22 at 22:44

score 7 · Answer 1 · answered Apr 23 '22 at 23:48

7

Tl-208, in the decay series, is a strong gamma-ray emitter. That's probably what you're seeing.

answered Apr 23 '22 at 23:48

John Doty

20,827

But it is not listed a gamma ray, but as beta (β− decay)(?). – Peter Mortensen Apr 24 '22 at 08:59
1

@Peter Beta decay disturbs the balance of the nuclear shell structure, so it often leaves the daughter nucleus in an excited state, and it soon loses that extra energy via gamma emission(s). Alpha decay generally has a more symmetrical effect on the shell structure, but some alpha decays are followed by gamma emission. – PM 2Ring Apr 24 '22 at 10:45

Does thorium-232 emit X-rays?

1 Answers1