ProblemSet-6-2005

ProblemSet-6-2005 - NE-524 Interaction of radiation with...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: NE-524 Interaction of radiation with Matter Problem Set #6 (Complete by 11/20/2005) 1) Aluminum bronze, an alloy containing 90% Cu and 10% Al by weight has a density of 7.6 g/cc. What are the linear and mass attenuation coefficients? ( Cu = 9.91 and Al = 4.45 barns) 2) Compute the thickness of Al and Pb to transmit 10% of a narrow beam of 0.1 MeV photons. 3) 4) What fraction of their energies do 1 MeV and 0.1 MeV photons lose if they are scattered through an angle of 90o? In an experiment, it was found that a 1 cm thick lead absorber attenuated a 10 MeV neutron flux to 84.5% of its initial value. What is the total cross section? (Pb atomic weight = 207.21, = 11.3 g/cc) A sample containing an unknown quantity of chromium is irradiated for one week in a thermal neutron flux of 10E11 n/cm2.sec. The resulting Cr-51 gamma rays produce a net counting rate of 600 counts per minutes in a scintillation counter with an efficiency of 10%. How many grams of chromium were in the original sample? - 5) - thermal neutron activation = 13.5 barns reaction: Cr-50 + n ----> Cr-51 + Cr-51 half life = 27.8 days Cr-50 forms 4.31% by number of the naturally occurring chromium Cr atomic weight = 52.01 Cr-51 branching ratio = 9.8% Answers: 1) 2) 3) 4) 5) 0.718 cm-1, 0.0944 cm2/g Al: 4.98 and Pb: 0.038 cm 1 MeV: 0.338 and 0.1 MeV: 0.836 5.12 barns 9.47E-6 grams ...
View Full Document

This note was uploaded on 04/11/2008 for the course CHNE 524 taught by Professor Mohagheghi during the Fall '08 term at New Mexico.

Ask a homework question - tutors are online