Software energy calibration

Itis difficultnowadays to separate the MCA as an electronic device and the software used to control it and handle the spectra it generates. Hardwired MCA instruments, such as the Canberra SlOO and the ORTEC MCB/Maestro MCA Emulator, did little more than acquire the spectra and store them, with facilities for two point energy calibration and ROl readout. One can expect all MCA systems to do the following ... 

S //Asa mediator between CFD calculations and macro-scale process simulations, the reactor geometry is represented by a relatively small number of cells which are assumed to be ideally mixed. The basic equations for mass, impulse and energy balance are calculated for these cells. Mass transport between the cells is considered in a network-of-cells model by coupling equations which account for convection and dispersion. The software is capable of optimizing a process in iterative simulation cycles in a short time on a standard PC, but it also requires experimentally-based data to calibrate the software modules to a specific micro reactor. 

The position of arrival, and hence the energy and angle of emission, is then calculated for each pair of electrons and the corresponding time-of-flight of each electron through the analysers is also calculated and used to correct the coincidence spectrum. The software allows the data to be displayed in a number of ways, and is also used to check the calibre of the data and to provide instrumental checks. 

You should find the WinLab (Perkin-Elmer) software used to control and to acquire GFAA data already downloaded. Retrieve and enter the software via the keyboard. The Pb HCL should turn on as well. A stable signal is necessary in order to continue. Proceed to autozero the detector, and if not satisifed, go to the realign lamps screen and adjust the physical position of the Pb HCL so as to bring the energy throughput near to that for the deuterium lamp. Set up a sequence to run a lab blank, a series of calibration standards for Pb, and one or more ICVs. 

The instructions with the software packages indicate how to determine / and a, how to measure the parameters of the efficiency calibration of the detector and convert it to specific counting geometries, and how to convert the peak areas into the mass firactions of the elements. The software packages have libraries of ko values, Qo values, mean resonance energies, half-lives, decay types, and the details of the decay schemes needed for true coincidence summing calculations. 

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