ApplyDeadTimeCorr-v1.rst

Description

Assuming that the InputWorkspace contains measured counts as a function of TOF, the algorithm returns a workspace containing true counts as a function of the same TOF binning according to

$$N = \frac{M}{(1-M*(\frac{t_{dead}}{t_{bin}*F}))}$$

where

N = true count
M = measured count
t_dead = dead-time
t_bin = time bin width
F = number of good frames

DeadTimeTable is expected to have 2 columns:

1. Integer type, containing spectrum number (not index)
2. Double type, containing t_dead value of the spectrum

Usage

Example - Applying the correction using custom dead times:

ExCustomDeadTimes

# Load single period of a MUSR run input = LoadMuonNexus('MUSR0015189.nxs', EntryNumber=1)

# Remove uninteresting bins input = CropWorkspace('input', XMin=0.55, XMax=12)

# Create a table with some arbitrary dead times dead_times = CreateEmptyTableWorkspace() dead_times.addColumn('int', 'Spectrum no.') dead_times.addColumn('double', 'Deadtime')

for i in range(1,65):

dead_times.addRow([i, 0.1])

output = ApplyDeadTimeCorr('input','dead_times')

original = Integration('input') corrected = Integration('output')

format_str = 'Spectrum: {0:d}; original: {1:.3f}; corrected: {2:.3f}'

for s in [0,32,63]:

print format_str.format(s, original.readY(s)[0], corrected.readY(s)[0])

Output:

ExCustomDeadTimes

Spectrum: 0; original: 6643.000; corrected: 6861.714 Spectrum: 32; original: 10384.000; corrected: 10928.727 Spectrum: 63; original: 8875.000; corrected: 9273.499

Example - Applying the correction using dead times stored in the Nexus file:

ExLoadedDeadTimes

# Load a MUSR run input = LoadMuonNexus('MUSR0015189.nxs', DeadTimeTable='dead_times')

# Remove uninteresting bins input = CropWorkspace('input', XMin=0.55, XMax=12)

# Apply the loaded dead times output = ApplyDeadTimeCorr('input','dead_times')

original = Integration(input.getItem(0)) corrected = Integration(output.getItem(0))

format_str = 'Spectrum: {0:d}; original: {1:.3f}; corrected: {2:.3f}'

for s in [0,32,63]:

print format_str.format(s, original.readY(s)[0], corrected.readY(s)[0])

Output:

ExLoadedDeadTimes

Spectrum: 0; original: 6643.000; corrected: 6670.079 Spectrum: 32; original: 10384.000; corrected: 10451.664 Spectrum: 63; original: 8875.000; corrected: 8922.105