Gamma-Ray Data for Neutron Activation Analysis

(Suggestion: Print this page to keep instructions handy before proceeding.)

Look up isotope corresponding to a given gamma ray

1. Access the Erdtmann and Skoya database on the Lund Nuclear Data WWW Service: http://nucleardata.nuclear.lu.se/database/es/
2. Enter the following:
• gamma-ray energy
• uncertainty (be a little generous!)
• limits on the half-life (suggested: 6 hours to 10,000 years)
• production: thermal neutron activation. (If there is no match, try fast neutron activation. Although the source was irradiated in a well thermalized part of the reactor, there may be a few products of fast neutron reactions.)
3. Click on "Submit Energy Search" to see specific gamma rays that satisfy the criteria

Note: You can also look up gamma rays in Table of Isotopes (ToI) decay database http://nucleardata.nuclear.lu.se/nucleardata/toi/radSearch.asp . The ToI database includes uncertainties, but does not allow one to specify a production method, which results in many more isotopes for a given gamma ray energy.

Look up all gamma rays for an isotope

1. Access the Table of Isotopes decay database on the Lund Nuclear Data WWW Service:  http://nucleardata.nuclear.lu.se/nucleardata/toi/nucSearch.asp
2. Enter the following:
• Mass number
• Either the atomic number Z or the Element symbol
3. Click on "Search"
4. Click on the isotope symbol to see a complete list of radiations. This will get you the gamma rays and x-rays from decay.

Thermal neutron capture cross sections

http://ie.lbl.gov/ngdata/sig.txt

This is a single table. The values you want are the 2200 m/s (thermal) cross sections labeled sigma(O), given in the adjacent columns labeled "Sigma" and "Unc." The units are barns (10^-24 cm^2). Where cross-sections are given for capture to more than one state (isomers) of the resulting nucleus, the energy of the state in keV is given in the first column.

Half lives and natural isotopic abundances

These are also available in the ToI database nuclide search.

Data on sample and irradiation (spring 2008)

Sample weight:	0.5440 +- 0.0001 (should have been measured)	g
Thermal neutron flux:	(~3 ) x 10^12	n/(cm^2s)
Start of irradiation:	Wednesday before lab, 15:40
Duration of irradiation	Mon/Wed groups: 10.00/20.00	minutes