CAN CHEMICAL ENVIRONMENT AFFECT NUCLEAR PROPERTIES?

[John Jacobus <crispy_bird@YAHOO.COM>]

I saw this through another e-mail server and thought

it would be of interest.



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-----Original Message-----

From: physnews@aip.org [mailto:physnews@aip.org]

Sent: Friday, September 10, 2004 11:32 AM

To: Jacobus, John (NIH/OD/ORS)

Subject: Physics News Update 700





PHYSICS NEWS UPDATE

The American Institute of Physics Bulletin of Physics

News

Number 700 September 10, 2004  by Phillip F. Schewe

and Ben Stein

	

. . .

CAN CHEMICAL ENVIRONMENT AFFECT NUCLEAR PROPERTIES?  A

new experiment shows that the decay lifetime of

radioactive beryllium-7 changes by almost 1% when

placed inside a carbon-60 molecule.  This is perhaps

the largest shift yet seen in a chemically induced

modification of a nuclear lifetime.   The Be-7 is

unstable and one way for it to decay is for the

nucleus to capture one of its own electrons, process

in which a proton is turned into a neutron. Now if the

Be atom lies in the cavity within a C60 molecule (in

which case it is referred to as endohedral Be, or

abbreviated further, Be@C60) the surrounding halo of

carbon-based electrons apparently modifies the

wave-functions of the beryllium-associated electrons

and the associated "phase space" so that the rate at

which electrons are captured by the Be nucleus  is

speeded up.  Previous attempts to modify nuclear

lifetimes through chemical means have resulted in

shifts that were at the 0.15% level.  The researchers

from Tohoku University and Yokohama National

University (Japan) doing the present experiment

believe that it would be premature to suggest that

this approach can be used to mitigate the problems of

storing radioactive materials, but, in the near term

the use of endohedral fullerenes (cargo-carrying C60

molecules) might lead to specialized radio-therapies

or tracers for tagging metabolic pathways in the body.

 (Ohtsuki et al., Physical Review Letters, 10

September 2004; Ohtsuki@LNS.tohoku.ac.jp)

. . .



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"A devotee of Truth may not do anything in deference to convention.  He must always hold himself open to correction, and whenever he discovers himself to be wrong he must confess it at all costs and atone for it."

Monhandas K. Gandhi, in "Autobiography"



-- John

John Jacobus, MS

Certified Health Physicist

e-mail:  crispy_bird@yahoo.com





		

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