On Fri, Jul 25, 2014 at 8:00 AM, Bob Higgins <rj.bob.higg...@gmail.com>
wrote:

One of the things about Hagelstein's proposition that bothers me is that
> the excited nucleus does not want to stay excited for very long - it decays
> in an incredibly short time.  Suppose you are de-exciting a dd* that wants
> to release 24 MeV of energy with a set of phonons at 10THz.  The frequency
> difference is 24MeV=5.8e21Hz compared to 10THz=1E13Hz or a ratio of 5.8E8.
>  If you are taking the energy away with a 5.8E8x lower frequency phonon, it
> seems like it would take 5.8E8x as long to extract the energy.  Can an
> excited nucleus be coerced into waiting to burp that long?  It seems like
> it would require extreme coupling between the excited nucleus and the
> lattice for that to happen - much more coupling than the exchange coupling
> of the electronic lattice can provide.
>

Yes -- your feeling about phonons is similar to mine (and, for me, spin
coupling, too).  The problem largely feels like a bandwidth/latency
optimization problem.  The compound nucleus is optimizing for the fastest,
highest throughput decay.  So it has different options (observed and
hypothesized):

   - gamma emission -- high latency, high throughput
   - kinetic disintegration (to 3He, t, etc.) -- medium latency, high
   throughput
   - coupling with phonon modes -- low latency, low throughput?
   - spin coupling -- low latency, low throughput?
   - electromagnetic impulse (EMP) -- low latency, high throughput?

(When seen in the above light, the optimized solution seems to me to be
EMP, assuming the different channels have been properly characterized.)

Eric

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