Compilation of gamma-rays available

[JMUCKERHEIDE@delphi.com]

From:   IN%"RADCH-L@frcpn11.in2p3.fr"  "liste de distribution pour les
RADIOCHIM ISTEs", IN%"WELSHA@KBPNFS01.ESKOM.CO.ZA"  "Andrew Welsh" 17-MAR-1995 
08:27:20.90 

Subj:   Compilation of gamma-rays available


Hi everyone

There have been a few messages lately about good references for
gamma-ray data.  I have recently competed a fairly thorough survey
of all references available to me and have compiled what I believe is
a high-reliability table of energies, yields and halflives.
I have distributed it to a number of people around our nuclear plant
(Chemists/physicists).
Let me quote from my foreword to give you a better idea of the
project:

"Significant gamma-emitters
Table of Energies, Yields and Halflives


Foreword

In the past Radiochemistry has had various nuclear data reference
works available, but the degree of agreement between them has
frequently been a cause for concern.  Thus it was felt that a
thorough compilation and evaluation  was necessary in order
 to establish one definitive and reliable source of nuclear decay
data. It represents many weeks of often tedious work, by a
number of people, as no fewer than ten separate references
 were included in the survey

The methodology was as follows:  The nuclides selected for
evaluation were essentially those currently in our analysis
libraries on site and at the Environmental Survey Laboratory,
and commonly-used calibration isotopes.  A decision was made
(arbitrarily) to include all energies whose yields exceed 1% and
these energies were then entered into a database.  Often there
were as many as ten data points for each energy.  The evaluation
and the actual decision of what energy, yield and halflife to accept
for each nuclide was performed by myself, and it must be said that
often it was a subjective decision.  I tried to avoid the simple
calculation of weighted averages - rather I chose values which were
consistent among the more reputable of the available references.
The spread of energies, yields and halflives found among the various
references was frequently quite disturbing.  However, I do believe that
the end result is far better than relying on any one or two "favoured"
reference works.  The information was scrutinised at each stage of
the compilation and evaluation process, often by four independent
people, and thus I have the confidence that there have been no
transcription errors whatsoever.

The references consulted were the following, in approximate
order of "reliability weighting":
. IAEA-TECDOC-619, X-ray and gamma-ray standards for detector
calibration, September 1991
. The Health Physics and Radiological Health Handbook, Revised Edition, 1992
. Atomic Data and Nuclear Data Tables, Volume 29, Number 2, September 1983
. Radioactive Decay Data Tables, US Department of Energy, April 1981
. Table of Isotopes, Seventh Edition, 1978
. Gamma-ray Spectrum Catalogue, Third Edition, Aerojet Nuclear Company, March
 1974
. Radiochemical Analyses Handbook, Framatome, pre-1982
. Amersham source catalogue
. Isotope Products Laboratories source catalogue, July 1993
. Other references of unclear origin, which were accordingly given
less weight in the evaluation.

The information is presented in two sections: the first ordered by
energy, and the second by nuclide name alphabetically.  The actual
data contained in each section is, however, completely identical.

The raw data from the first stage of compilation is in the file
NUCLIDES.MDB (and the associated .IDB file) which is in
Microsoft Access 3 format.  This file contains all the information
from all the reference works, and is thus of interest if it is desired
to compare the degree of agreement between the various
references.  It is larger than 500 kb.  The few errors that were
identified were not corrected in this file - for this information,
the NUCFINAL.* files and the annotated printout in my possession
should be consulted.  This printout also provides details of the
evaluation process.
The corrected final data is in the files NUCFINAL.MDB (and .IDB)
and NUCFINAL.XLS, which is in Microsoft Excel 5 format.  "



I would be very willing to share this information with anyone who is
interested, for free.  Though I have great faith in the accuracy of
the project, I can obviously not take responsibility for any errors
that may still be lurking.
If anyone would like the files, e-mail me and I will send them off to
you by e-mail.

Regards
Andrew Welsh
Radiochemist
Koeberg Nuclear Power Station
Cape Town
South Africa