FilterBadPulses v1

../_images/FilterBadPulses-v1_dlg.png

FilterBadPulses dialog.

Summary

Filters out events associated with pulses that happen when proton charge is lower than a given percentage of the average.

Properties

Name Direction Type Default Description
InputWorkspace Input EventWorkspace Mandatory An event workspace
OutputWorkspace Output EventWorkspace Mandatory The name to use for the output workspace
LowerCutoff Input number 95 The percentage of the average to use as the lower bound

Description

The algorithm looks at sample logs (“proton_charge”), finds the mean, and rejects any events that occurred during a pulse that was below a certain percentage of that mean. This effectively removes neutrons from the background that were measured while the accelerator was not actually producing neutrons, reducing background noise.

Usage

Example - Using a simple proton charge log

ws = CreateSampleWorkspace("Event",BankPixelWidth=1)

AddTimeSeriesLog(ws, Name="proton_charge", Time="2010-01-01T00:00:00", Value=100)
AddTimeSeriesLog(ws, Name="proton_charge", Time="2010-01-01T00:10:00", Value=100)
AddTimeSeriesLog(ws, Name="proton_charge", Time="2010-01-01T00:20:00", Value=100)
AddTimeSeriesLog(ws, Name="proton_charge", Time="2010-01-01T00:30:00", Value=100)
AddTimeSeriesLog(ws, Name="proton_charge", Time="2010-01-01T00:40:00", Value=15)
AddTimeSeriesLog(ws, Name="proton_charge", Time="2010-01-01T00:50:00", Value=100)
AddSampleLog(ws,"gd_prtn_chrg", "1e6", "Number")
wsFiltered = FilterBadPulses(ws)

print ("The number of events that remain: %i" % wsFiltered.getNumberEvents())
print ("compared to the number in the unfiltered workspace: %i" % ws.getNumberEvents())

Output:

The number of events that remain: 950
compared to the number in the unfiltered workspace: 1900

Categories: Algorithms | Events\EventFiltering