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&SIGNAL: PLOT-FIELD: functions

charges

The induced charges are computed by first calculating a drift-line of the requested type and then integrating the internal product of drift velocity and weighting field over the drift-line. The charge thus obtained is multiplied with the charge of the particle that has been drifted.

The charge should be +1 or -1 for a particle drifting from the read-out electrode to another conductor and 0 for a particle that drifts between conductors that are not read out.

The charge induced over a given path should, apart from the sign, should not depend on the type of particle that drifts. However, in the presence of a magnetic field, electrons and ions will in general follow different paths, may therefore end up at different points, and hence induce different charges.

Charges are expressed in multiples of the electron charge.

The electrode whose weighting field is to be used can be set with the GROUP keyword. You can limit the charge integration to a time window by means of the TIME-WINDOW keyword.

status

The numeric status codes indicate where the particle ended up. They have a 1-1 correspondence with the status strings displayed in regular program output.

times

The times are the total drift time for particles of the selected type from the position at which the function is to be evaluated until the particle leaves the AREA, hits an electrode, exceeds the maximum number of steps, is abandoned etc.

The times are expressed in \μsec.

weighting_field

The weighting field is the field with which the drift velocity of a moving charge is multiplied to obtain the current induced in the various electrodes.

There is one such field per electrode or per group of sense wires.

This field is computed by setting the read-out electrode to unit voltage and earthing all other conductors.

The unit of the weighting field is 1/cm.

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Formatted on 21/01/18 at 16:55.