SIGNAL-PARAMETERS 

&SIGNAL: SIGNAL-PARAMETERS


AVERAGE-SIGNAL

Switching on this option makes that the total induced charge corresponds closely to the integral of the signal that is output by the program. This is less trivial than it may sound since signals can contain structure on a much smaller time scale than the binning of the signal.

The averaging is done with an 2*n_average+1 point Newton-Raphson integration over a time bin centred at the point in time indicated in the output, interpolating the signal vector with a polynomial order set with INTERPOLATION-ORDER.

[By default, 5 points are used, i.e. n_average is set to 2.]


INTERPOLATION-ORDER

In order to average the signal over a time bin, the signal is interpolated with polynomials of order n_order, and then integrated using the Newton-Raphson technique over 2*n_average+1 points. The n_average parameter is set with the AVERAGE-SIGNAL option.

The parameter n_order should not be chosen large since especially electron pulses rise very fast. This can easily give rise to interpolated values of the wrong sign.

[A value of 1 is therefore recommended, and is also default.]


SAMPLE-SIGNAL

If this option is switched on, then the signal that the program returns corresponds to the current at the point in time indicated in the output. Any fine structure smaller than the binning is lost, which may lead to incorrect integrated currents. Also, the signal when summed will not be normalised.

[By default, AVERAGE-SIGNAL is used with 5-point integration.]


SUM-SIGNAL

If this option is switched on, then the signal between integration steps is assumed to be constant. The signals will be correctly normalised to the extent that this assumption holds. This is the appropriate setting for Monte_Carlo and and microscopic drift-line integration, but not for Runge_Kutta_Fehlberg integration.

[By default, AVERAGE-SIGNAL is used with 5-point integration.]


INTEGRATE-WEIGHTING-FIELD

Only used with microscopic drift-line integration.

Requests 6-point Gaussian integration of the weighting field over a drift-path segment when computing the induced current. This is considerably more precise in case long steps are taken because of sparse drift-line sampling as set with the step_size option of the INTEGRATION-PARAMETERS command. The only disadvantage of this over the alternative SAMPLE-WEIGHTING-FIELD, is that the calculation time is larger.

[Default is 6-point Gaussian integration.]


SAMPLE-WEIGHTING-FIELD

Only used with microscopic drift-line integration.

Requests mid-point sampling of the weighting field over a drift-path segment when computing the induced current.

[Default is 6-point Gaussian integration.]


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