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Handgun ammunition contains Ba and Sb compounds. Firing a handgun leaves residues of these elements in microgram quantities on the back of ones hand. Such quantities are 1000 times above the detection threshold for neutron activation analysis for Ba and Sb. Assuming a swab is taken from the back of a suspects hand:
If analysed via slow neutron activation, determine which isotope of Sb is likely to be created. Then, consult the National Nuclear Data Centre (http://www.nndc.bnl.gov/nudat2/) and determine the gamma radiation that will be emitted.
What is the energy of the most intense gamma peak? (in keV)
(assume the original target nuclei are those which are naturally most abundant)
121Sb is the most abundant isotope of Sb, so I assume that is the target nuclei. If we are analyzing it via neutron activation that would add 1 neutron to it's mass number, making it 122Sb
I have the decay radiation information for 122Sb here: http://www.nndc.bnl.gov/nudat2/decaysearchdirect.jsp?nuc=122SB&unc=nds
I'm not really sure what I'm looking for on the page though. I believe the answer is 564.24 keV, with an intensity of 70.67 %.
I also found this image from a neutron activation experiment that supports this:
https://carlwillis.files.wordpress.com/2011/09/sb_activation.jpg
If analysed via slow neutron activation, determine which isotope of Sb is likely to be created. Then, consult the National Nuclear Data Centre (http://www.nndc.bnl.gov/nudat2/) and determine the gamma radiation that will be emitted.
What is the energy of the most intense gamma peak? (in keV)
(assume the original target nuclei are those which are naturally most abundant)
121Sb is the most abundant isotope of Sb, so I assume that is the target nuclei. If we are analyzing it via neutron activation that would add 1 neutron to it's mass number, making it 122Sb
I have the decay radiation information for 122Sb here: http://www.nndc.bnl.gov/nudat2/decaysearchdirect.jsp?nuc=122SB&unc=nds
I'm not really sure what I'm looking for on the page though. I believe the answer is 564.24 keV, with an intensity of 70.67 %.
I also found this image from a neutron activation experiment that supports this:
https://carlwillis.files.wordpress.com/2011/09/sb_activation.jpg
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