Re: What is meant by "forbiddenness of the decay path?"

["Drew Thatcher" <Thatcher.Drew@home.com>]

Try and find a copy of an introductory nuclear physics text.  My copy is
"Introductory Nuclear Physics" by Kenneth Krane.  In the discussion of
angular momentum and parity selection rules, you'll find a great discussion
of allowed and forbidden decays.  About six pages of text explain the topic.

Since there are several nuclear physicists on this listserver I won't get
myself into trouble by trying to summarize this information.  I'll merely
state that forbidden decays have a lower probability of occurence of about
E-04 that of allowed decays.  Each higher order of forbiddenness results in
a transition probability that is smaller than the previous by about E-04 as
well.

Regards,
Drew Thatcher

Andrew H. Thatcher, MSHP, CHP
Washington Department of Health
thatcher.drew@home.com
360.236.3255 voice
801.858.7891 fax
-----Original Message-----
From: Jacobus, John (OD) <JJacobus@exchange.nih.gov>
To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
Date: Wednesday, November 10, 1999 4:58 PM
Subject: What is meant by "forbiddenness of the decay path?"


>I am reviewing a manual that discusses beta decay, which indicates that
some
>paths are forbidden?  Can anyone tell me that refers to?  Are there
>probabilistic values associated with this?
>
>-- John
>
>"It isn't necessary to imagine the world ending in fire or ice-there are
two
>other possibilities: one is paperwork, and the other is nostalgia."
>-Frank Zap
>
>
>
>John Jacobus, MS
>Health Physicist
>National Institutes of Health
>Radiation Safety Branch, Building 21
>21 Wilson Drive, MSC 6780
>Bethesda, MD  20892-6780
>Phone: 301-496-5774      Fax: 301-496-3544
>jjacobus@exchange.nih.gov (W)
>jenday@ix.netcom.com (H)
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