RE: Decay properties change at temperature extremes?

["Franta, Jaroslav" <frantaj@aecl.ca>]

Radsafe colleagues,

I'm not sure whether this strays too much from permitted RADSAFE topics, but
your question is one that's been puzzling me a little as well -- especially
since last year's announcement of the famous experiment of super-cold Bose
Einstein Condensation (BEC) of atoms, using laser trapping & cooling. 
The experiment involved neutral atoms (magnetic traps do work for neutral
particles - the field
interacts not with the charge but with the magnetic dipole moment), so it
should, in theory be possible to condense a bunch of neutrons also (the
laser frequency would probably have to different ??).
The point is that "free" neutrons have a half-life of ~ 12 minutes, whereas
neutrons inside (stable) atomic nuclei and in neutron stars are stable (or
extremely long-lived). So, one would expect that a BEC made of neutrons
would behave like an atomic nucleus or a piece of neutron-star-stuff  --
with unlimited life span. Wonder whether the transition would be sudden, or
whether there would be a gradual increase in life as the BEC state (the
neutron wavefunctions will start to interact with each other) is approached
? Presumably, a BEC made of atoms with radioactive nuclei would also result
in lifetime increases (?) - and would be easier to do experimentally than
the pure neutron version... maybe someone's even tried to do this already ?

Jaro
frantaj@aecl.ca
> ----------
> From: 	Langenegger, Armin[SMTP:alang@allsaintshealthcare.org]
> Reply To: 	radsafe@romulus.ehs.uiuc.edu
> Sent: 	Monday, November 15, 1999 11:56 AM
> To: 	Multiple recipients of list
> Subject: 	RE: Decay properties change at temperature extremes?
> 
> Hello Bob,
> 
> There was a physics today article a few years back that showed
> polarization
> of beta decay at ultra low temps, that is the directions of the ejected
> beta
> was in preferential directions as I recall.
> 
> Try going to the www.aip.org <http://www.aip.org>  web site and searching
> the archives of physics today for the article.
> 
> Armin Langenegger MS DABMP
> 
> 
> 		-----Original Message-----
> 		From:	Zoon, Robert (OD) [mailto:razoon@exchange.nih.gov]
> 		Sent:	Monday, November 15, 1999 9:53 AM
> 		To:	Multiple recipients of list
> 		Subject:	Decay properties change at temperature
> extremes?
> 
> 		Dear Radsafer's:
> 
> 		One of our scientists has posed the question below and I
> said that, although I
> 		believe the answer is no from everything I have been taught
> about radioactive
> 		decay, I would try to see if any research has been done in
> this area:
> 
> 		The question is:  Is there any change in the decay
> properties of alpha or beta
> 		emitters at extremes of temperature, either high or low?
> His specific range of
> 		interest was 0 - 500 degrees Kelvin.  I wouldn't expect any
> change at 500 K,
> 		which is only about 227 degrees C.  However, a lot of
> strange things happen as
> 		materials approach absolute zero.
> 
> 		Any help would be greatly appreciated, even a contact at a
> university or
> 		research laboratory.
> 
> 		Bob Zoon
> 		Radiation Safety Officer, NIH
> 		301-496-2254
> 
> 	
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