Half-life of radioactive isotopes near 0 K.

DavidZuccaro

Would the observed half-life of a sample of a radioactive isotope (eg. iodine 131) be different from the nominal half-life when it is cooled down to a temperature near absolute zero.

Have there been any experiments conducted to examine this question?

Mark M

Welcome to PF!

Temperature does not have any effect on radioactive half-life. Remember that temperature is the average atomic motion. Decay is mediated by the weak nuclear force, which has no relation to the movement of the particle.

DavidZuccaro

Fair enough.

So my follow up question is does the half-life of a particular isotope vary in accordance with any other physical property such as electric field - excepting weak nuclear force which you have mentioned.

mfb

Electric fields are not strong enough to have an impact - in addition, if the nucleus sees them, it just accelerates. And electric field gradients are even smaller, when applied to the size of a nucleus.

Three ways to influence nuclear transitions:
- Electron capture needs electrons, and depends on the presence of electrons nearby. There, you can alter the speed of the process.
- In a similar way, you could shoot a lot of neutrinos and stimulate proton<->neutron transformation. However, I do not think this would give a measurable effect.
- Pressure similar to the conditions in white dwarfs or neutron stars. This allows to get particles close enough to have a significant influence.