Re: Total U-238 activity

["Charles Meyer" <Charles.Meyer@tdh.state.tx.us>]

> Date:          Mon, 22 Jun 1998 12:44:37 -0500 (CDT)
> Reply-to:      radsafe@romulus.ehs.uiuc.edu
> From:          Les Slaback <lester.slaback@nist.gov>
> To:            Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Subject:       Total U-238 activity

> As Ron K. pointed out, restricting ourselves to the theoretical question ....
> 1.  The entry in the last two versions of the RHH erroneously shows two
> nuclides in the split following the Pa-234m decay.  Only the .13% Pa-234
> should be there (shown as Pa235 IT, should be Pa-234).
> 2. Ignoring some fine details in decay equilibrium this branch then adds
> .0013 Bq to the decay total.
> 3. Taking those details into account note that the daughter activities are
> not exactly equal to the parent activity, but are constant in a fixed ratio
> at equilibrium which for long lived parents is very close to 1.
> 4. As to 'PC correctness', given that the attribution of 'daughter' only
> applies to the unstable progeny how can one discuss the point without
> getting into hotter water?
> Disclaimer:  the above are the personal musings of the author, and do not
> represent any past, present, or future position of NIST, the U.S. government,
> or anyone else who might think that they are in a position of authority. 
> Lester Slaback, Jr.  [Lester.Slaback@NIST.GOV] 
> NBSR Health Physics 
> Center for Neutron Research 
> NIST 
> Gaithersburg, MD  20899 
> 301 975-5810
>

Actually, that should be P correctness. 
<><><><><><><><><><><><><><><><><>            
<>    Charles R. (Russ) Meyer                  <>
<> Email:charles.meyer@tdh.state.tx.us 
<>     Phone:(512)834-6688                       <>
<>        Fax:(512)834-6654                        <>
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