Resolution of Time-Dependent Gamma Spectra with a Digital Computer and Its Use in Activation Analysis

Modern trends in activations analysis vol. 2

“…before magic neutron or proton numbers [31]. They also follow Mattauch's rule [32,33] , namely that isomers do not occur with even-even nuclei, that all nuclei with a spin of 9/2 in the ground state have a metastable state and that nuclei with a spin of 3/2 or 5/2 in the ground state have no metastable state.…”

“…Different equations have been proposed to describe an unmoderated fission flux [16][17][18] ®(E)=k l exp (-E) sinh V2E (31) = k2 exp (-1.036£) sinh \/2.29£ (32) = k 3 VE exp (-0.775E) (33) For reactor irradiations one can consider that in many instances this fast neutron spectrum is little disturbed above 2 MeV.…”

“…This system incorporates magnetic tape, a large area CRT display oscilloscope, RADIATION DETECTION AND DATA HANDLING function keyboard, and light pen. This system has been employed to develop techniques for the analysis of 4096 channel pulse height spectra to obtain gamma-ray energies and intensities through the use of manmachine interaction with a graphical system [33,34]. More recently a larger system, shown in Figure 45, has been employed to expand this capability.…”

“…An example of how these devices are used might be to describe a procedure used to analyze Ge(Li) spectra using graphical techniques [33,34] . Assuming that a portion (256 channels) of a 4096 channel pulse height spectrum is displayed on the large screen oscilloscope, as if one Display of oscilloscope screen showing concept of information retrieval using light pen.…”

“…Computer preparation of data for the catalog included (1) reduction of the number of channels of data by combining data in adjacent pairs of channels in order to smooth the spectra and reduce statistical 1 173 scatter, (2) correcting for counting losses caused by dead time, (3) converting the spectra from counts per channel to counts per channel per minute, (4) subtraction of background, ( 5) normalization to a "standard" flux, and ( 6) preparing a semi-log plot of the spectrum. Analysis of unknowns [33] was then begun by visual identification of spectral components using the catalog. Computation of the total peak area for the component having the highest energy gamma-ray peak was used for quantitative result computation for the element from which the gammaray emitter was formed.…”