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Comment: Re:isotope vs isomer (Score 3, Interesting) 499

by subnuclear (#9093682) Attached to: The Controversy of a Potential Hafnium Bomb
You just have to make a lot of halfnium from some nuclei and some of the halfnium will have this higher energy spin-state spontaneously. You can seperate different spin-states using strong magnets since the amount a particle bends in a magnetic field depends on its spin. The X-rays aren't used to controlled the spin but to the kick the nucleus in to a higher-energy and less stable spin-state. The nucleus then decays into the ground state releasing a much more energetic photon than the X-ray you put in.

However, the cross-section (the probability of occurance) for this X-ray excitation is incredibly small in every isomer studied. It usually requies much more energy to be put in than can be produced. Carl Collins's data shows a much larger cross-section (10,000x larger!), but follow-up experiments by Argonne National Labs and others haven't seen a damn thing. Collins data is not very convincing to anyone, but Collins

One of the chief duties of the mathematician in acting as an advisor... is to discourage... from expecting too much from mathematics. -- N. Wiener

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