Effect of temperature on radioactivity? I'm researching the effect of temperature on uranium radioactivity, however I can't find any solid empirical evidence to prove the notion that temperature does not affect radioactivity.
Can anyone link to some solid data on the topic, or offer some advice on where to find such data?
 A: What do you mean by "prove"? If you mean in a strict mathematical sense, then looking for such assurances is a lost cause.
There are quite a wide variety of papers on this matter. Curie attacked this particular problem in 1913 with radium. They immersed a radium source in liquid hydrogen for more than an hour and didn't find a change of more than 0.1% in its activity. You can read more from the paper by Curie & Kamerlingh Onnes entitled, "The radiation of radium at the temperature of liquid hydrogen" in KNAW, Proceedings, 15 II, 1912-1913, pp. 1430-1441. People even claimed, from Russia, that polonium's activity varied depending on geography. Hardly the case.
More recently, work has been done on the half-life decay rate of $^{97}{\rm Ru}$ without seeing a noticeable temperature dependence near 20K compared with RT. See the paper by Goodwin, Golovko, Iacob and Hardy entitled, "Half-life of the electron-capture decay of $^{97}\rm Ru$: Precision measurement shows no temperature dependence" in Physical Review C (2009), 80, 045501, arXiv:0910.4338.
It could be that there is a small dependence, but not even the Russian paper mentioned above by Martin agrees there is a measurable temperature dependence.
A: There are suggestions that low (>1K) temperatures slow the decay rate - at least for some large atoms
Reference: G. M. Gurevich et al.: The effect of metallic environment and low temperature on the 253Es $\alpha$ decay rate. Link
A: My understanding is that at absolute zero, molecular vibration even ceases with the exception of zero-point energy. Since this is applicable to Nobel Gases, we can only extrapolate other inferences to other objects. Ionizing radiation if I am not mistaken occurs more rapidly as the fissionable material is condensed closer and closer by pressure. That is the working theory behind the Atomic Bomb. Compress fissile material to the point of criticality and you have a big release of energy. One might suppose that at absolute zero, no further compression of material may happen so therefore the rate of decay would be lessened to a greater extent than in nature. Just my two cents worth.
