Pixie16 Parameters

This page discusses some of the essential Pixie Parameters as outlined below.

• Module Parameters
• Module Control MODULE_CSRB
• Trigger Control TrigConfigX
• Trigger Filter Decimation FAST_FILTER_RANGE
• Energy Filter Decimation SLOW_FILTER_RANGE
• Channel Parameters
• Channel Control CHANNEL_CSRA
• Trigger Risetime TRIGGER_RISETIME
• Trigger Flattop TRIGGER_FLATTOP
• Trigger Threshold TRIGGER_THRESHOLD
• Energy Risetime ENERGY_RISETIME
• Energy Flattop ENERGY_FLATTOP
• Tau TAU
• Trace Length TRACE_LENGTH
• Trace Delay TRACE_DELAY
• Channel Timing Parameters

Module Parameters

TrigConfigX

TrigConfig Calculator

Channel Parameters

This section describes the Pixie16 channel parameters including those related to the trigger (fast) and energy (slow) trapezoidal filters that do the initial processing of signals.

CHANNEL_CSRA

Trigger Filter

This trapezoidal filter is designed to trigger the system to perform further signal processing and possibly lead to data recording based on the triggering settings.

TRIGGER_THRESHOLD

This is a channel parameter which sets the threshold above which the trigger filter must exceed to continue processing. Typically this is set as low as possible without triggering on noise.

TRIGGER_RISETIME

This is a channel parameter which sets the risetime of trapezoidal filter. Increasing this value will average mor samples together.

TRIGGER_FLATTOP

Energy Filter

This is a trapezoidal filter that is designed to extract the energy of a pulse after the system had been triggered. This filter is run nearly independently on every channel. The following settings are all channel parameters.

ENERGY_RISETIME

This is a channel parameter and sets the risetime of the trapazoidal filter. This value has a strong impact on the energy resolution. By increasing its value the resolution drops until reaching a point where further increase will cause increased noise to be incorporated into the filter. Remember that the filter length is 2 x Risetime + Flattop and that the dead time will increase as filter parameter lengths are increased.

ENERGY_FLATTOP

This is a channel parameter and sets the flattop or gap of the trapezoidal filter. Its value should be roughly the same as the pulse rise time.

TAU

This parameter is the most critical for the energy computation. It compensates for the previous decaying pulse. It should be set roughly to the decay constant of the attached sginals.

Timing