Application Notes to Multiparameter Systems |
Introduction
Coincidence measurements are a powerful tool in physics for observing complex phenomena.
The close time relation of two or more parameters assures that such an event results from a single physical process.
The simultaneous acquisition of two or more physical parameters using ADC’s or TDC’s result in set of numbers that characterize a a specific physical process in detail.
This set of numbers can be looked at as a n-dimensional vector. The histograming (accumulation) of a large number of these vectors result in a multidimensional spectrum that is usually stored in the memory of a PC
As n-dimensional spectra can not be visualized on a PC-monitor and are very difficult to imagine by the human mind it is necessary to compute projections in a single or two dimensions for easy viewing on a computer monitor.
Conditions are usually applied on the remaining parameters. Analysis software is available to meet typical requirements of the experimenter.
An alternative storage facility is in "list-mode" – this means the capability of the system to store the incoming events in the order of arrival in a mass storage devices like hard disks (HDD),
The advantage of a data storage in list mode is that one set of experiment data can be analyzed on and on using the same data with varying analysis parameters. We call this Replay – an efficient way to save the user from repeating the experiment many times if the analysis parameters are not set to an optimum. If properly stored the data saved in list mode can be analyzed even years later using different analysis algorithms without the need to repeat the experiment.
A few examples of the many different applications where our multiparameter system is used are:
Short descriptions of the MPA-3 multiparameter system: