Update on T2.4:
Gd-lined plastic scintillator detector
Raffaella De Vita
INFN
November 21st 2012
Outline
• Detector Concept and Prototype Layout
• Progresses since last SCINTILLA meeting
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Tests of neutron capture medium and improvements of neutron
capture efficiency
Development and implementation of new readout electronics and
user interfaces
Data outputs and format
Preparation of DL2.4.2
• Detector layout for next technology benchmark
• Future activity and time schedule
21/11/2012
SCINTILLA
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Detector Concept and Prototype Layout
5” PMTs
(20x40x80 cm3)
LAYOUT:
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•
•
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Plastic scintillator layers, wrapped in reflective
foils and interlayered by Gd-coated foils
VME-based DAQ (commercial boards):
Total volume = 64 liters
Front surface = 3200 cm2
OPERATION:
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•
Detect presence of radioactive material via
increase of pulse rates
Discriminate gammas and neutrons by
different event topology:
- E>5 MeV
- Coincidence of Prompt-delayed events
21/11/2012
SCINTILLA
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Neutron Absorber Test Setup
Validation of simulation results on
Gd-oxide amount via measurement in
dedicated test setup
• Measurements of neutron capture
time for different thickness of the
scintillator and Gd-Oxide
• Reduction of capture time by a factor
2.5 for an increase of absorber
thickness of a factor 4
➝ will be implemented for February
technology benchmark
• Reduction of capture time by a factor
1.5 for smaller scintillator thickness (1
cm vs. 2 cm)
• ➝ will be implemented in final
prototype
21/11/2012
SCINTILLA
2cm-thick scintillator
1cm-thick scintillator
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DAQ Layout
Hardware instrumentation
Cables and connections with the detector
Temperature monitoring embedded on the
HV power supply boards
21/11/2012
SCINTILLA
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The acquisition program at a glance…
At startup:
Checks the status of the hardware (enviromental variables)
Sets the HV channels to power on the PMTs
Properly initializes the digitizer board (thresholds, acquisition mode,
integration window, …)
During acquisition:
Monitors the rates of photon-like and neutron-like events
Notifies neutron/photon alarms if rates exceed threshold
Writes data to output files (N42.42 and “expert” formats)
At the end of the acquisition:
Analyzes the data (energy and time distributions)
Shows summary plots on the Data Viewer
21/11/2012
SCINTILLA
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First Tests
Measurement of
rates, spectra and
prompt-delayed
coincidences with
AmBe source
21/11/2012
SCINTILLA
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N42.42 XML File structure
The XML file is one of the output of our system.
The planned XML file format has a structure divided
into 3 parts:
1. The HEADER: It describes the run taken. There is
the list of parameters and definitions used for the
analysis, followed by the environmental variables
2. The CENTRAL PART: It contains all the data rates,
counts and alarms recorded with a certain
frequency
3. The END of File: Summary of all the counts, mean
rates AND all the alarms appeared along the run
selected by radiation hypothesis (n and gamma)
Header
Place & Date
Measurement Type
Environmental variables
System configuration (HV, ..)
N and gamma energy range
Central part
Date, counts, alarms,
backgrounds
End of file
Time range
n and gamma counts
n and gamma rates
Alarm settings
Alarms
Summary
21/11/2012
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XML Header example (.xml file)
<!– HEADER -->
<?xml version="1.0" encoding="UTF-8"?>
<?xml-model href="http://physics.nist.gov/N42/2011/N42/schematron/n42.sch" type="application/xml"?>
<RadInstrumentData>
<Remark> EXAMPLE XML FILE 2011 version </Remark>
<Remark> ===== HEADER ===== </Remark>
<Remark> Measurement Date: 003-11-22T23:45:00.6-07:00 and Location: Genova </Remark>
<RadDetectorInformation id="RPM INFN-ANSALDO">
<RadInstrumentManufacturerName>INFN-ANSALDO</RadInstrumentManufacturerName>
<RadInstrumentIdentifier> Aa1 </RadInstrumentIdentifier>
<RadInstrumentModelName> Prototype 1 </RadInstrumentModelName>
<!-- RadInstrumentDescription, RadInstrumentVersion -->
<RadInstrumentClassCode>Portal Radiation Monitor</RadInstrumentClassCode>
<RadInstrumentCharacteristics>
<Characteristic>
<CharacteristicName> Arm1 </CharacteristicName>
<CharacteristicValue>40</CharacteristicValue>
<CharacteristicValueUnits>centimeters</CharacteristicValueUnits>
<CharacteristicValueDataClassCode>double</CharacteristicValueDataClassCode>
</Characteristic>
</RadInstrumentCharacteristics>
</RadDetectorInformation>
<RadDetectorInformation id="Aa1"> <!-- DNDO official name to be searched -->
<RadDetectorName>Bar1 -Aa1-</RadDetectorName>
<RadDetectorCategoryCode>Gamma-Neutron deiscriminator</RadDetectorCategoryCode>
<RadDetectorKindCode>PVT</RadDetectorKindCode>
<RadDetectorDescription> Comment about single bar </RadDetectorDescription>
<RadDetectorLengthValue units="cm">40</RadDetectorLengthValue>
<RadDetectorWidthValue units="cm">1</RadDetectorWidthValue>
<RadDetectorDepthValue units="cm">10</RadDetectorDepthValue>
</RadDetectorInformation>
<EnergyWindows id="GammaWindowSettings”>
<WindowStartEnergyValues>0 0 100</WindowStartEnergyValues>
<WindowEndEnergyValues>100 3000 400</WindowEndEnergyValues>
</EnergyWindows>
<Remark> User: Operator </Remark>
XML Center and End of File example (.xml file)
<!-- CENTRAL PART -->
<Remark> ==== CENTRAL PART ==== </Remark>
<!-- Per le environmental variables ci pensiamo poi -->
<!-- Background -->
<RadMeasurement>
<MeasurementClassCode>Background</MeasurementClassCode>
<StartDateTime> 003-11-22T23:45:00.6-07:00 </StartDateTime>
<RealTimeDuration> PT100M </RealTimeDuration>
<GrossCounts radDetectorInformationReference="Bar1"
energyWindowsReference="GammaWindowSettings">
<CountData> 5 22 200 </CountData> <!-- With Gammawindows -->
</GrossCounts>
<GrossCounts radDetectorInformationReference="Bar2" >
<CountData> 5 </CountData> <!-- Without Gammawindows -->
</GrossCounts>
</RadMeasurement>
<!-- NEUTRONS -->
<RadMeasurementGroup id="Neutrons"/> <!-- The same for Photons -->
<RadMeasurement>
<MeasurementClassCode> Measurement Run </MeasurementClassCode>
<StartDateTime> 003-11-22T23:45:00.6-07:00 </StartDateTime>
<RealTimeDuration> PT0.1S </RealTimeDuration>
<GrossCounts radDetectorInformationReference="Bar1">
<CountData>5 22 200</CountData>
</GrossCounts>
<AverageCountRateValue> 12 </AverageCountRateValue>
<AverageCountRateUncertaintyValue> 0.2
</AverageCountRateUncertaintyValue>
</RadMeasurement>
21/11/2012
<!-- END of File -->
<Remark> ==== END of File ==== </Remark>
<AnalysisResults type="Arm1">
<AnalysisComputationDuration> PT2S </AnalysisComputationDuration>
<GrossCountAnalysisResults id="Neutrons"
radDetectorInformationReference="Bar1">
<TotalCountsValue> 3045 </TotalCountsValue>
<AverageCountRateValue units="CPS"> 100 </AverageCountRateValue>
<AverageCountRateUncertaintyValue units="CPS"> 0.1
</AverageCountRateUncertaintyValue>
</GrossCountAnalysisResults>
<GrossCountAnalysisResults type="Photons">
<TotalCountsValue> 3045 </TotalCountsValue>
<AverageCountRateValue units="CPS"> 200 </AverageCountRateValue>
<AverageCountRateUncertaintyValue units="CPS"> 1.2
</AverageCountRateUncertaintyValue>
</GrossCountAnalysisResults>
<RadAlarm id="Neutrons" radDetectorInformationReference="Bar1">
<RadAlarmDescription> Average rates alarms for Neutrons: 3
</RadAlarmDescription>
</RadAlarm>
<RadAlarm id="Photons" radDetectorInformationReference="Bar1">
<RadAlarmDescription> Average rates alarms for Photons: 0
</RadAlarmDescription>
</RadAlarm>
<AnalysisResultDescription>
Possible State: Probable NORM.
Alarm active for photons radiations: NO.
Alarm active for neutron radiation: YES.
Error messages: NO. Detector status: ACTIVE.
</AnalysisResultDescription>
</AnalysisResults>
</RadInstrumentData>
SCINTILLA
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Preparation of DL2.4.2
Deliverable 2.4.2: Technical Design of the Gd-Lined Plastic Scintillator
Detector with Integrator Initial Guidelines for the Integration and
Deployment of the Technology
Deadline: 31/12/2012
Updated detector design:
• Documentation of neutron capture studies ➝ first draft available
• Documentation of new electronic readout system ➝ first draft available
• Documentation of updated detector layout ➝ in progress
Implementation of Integrator Guidelines:
• Documentation of data output and N42.42 output format ➝ in progress
• Other guidelines ➝ to be started
21/11/2012
SCINTILLA
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System Layout for Technology Benchmark
• One pillar configuration
• System size:
• Services:
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•
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Power line: 220 V, XXX W
One optical fiber from
electronic box to system
console (5 m, can be
increased)
Ethernet line from system
console to benchmarking
server (?)
Optical Fiber to
System Console
source
DETECTOR
Detector: 60x30x195 cm3
Electronic box: 60x15x40 cm3
System console: 1 pc
ELECTRONICS
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220 V
21/11/2012
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Future Activity and Time Schedule
Work Plan:
• Complete modifications of neutron absorber in the detector prototype
• Complete the development of the new electronic readout and user
interface
• Complete he implementation of the N42.42 output format
• Implement integration requirements for technology benchmark
• Test new system with gamma and neutron sources in INFN lab
scintilla_f plan
11/ 14/ 12 8:09 PM
Task
Oct 2 0 12
1) Prototype hardware modification (neutron absorber)
1.1) design
1.2) implem entation
Eff ort
Dec 2 0 1 2
Jan 2 01 3
2w
2w
2) Development of readout software and user interface
4w 2d
3) Test of new readout on detector prototype
2w 3d
4) First m easurem ent cam paign in INFN lab
1w
5) Second measurement campaign in INFN lab
1w
21/11/2012
Nov 2012
4w
SCINTILLA
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backup
SCINTILLA
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XML example (web-browser)
The final printed draft of the XML file is:
EXAMPLE XML FILE 2011 version ===== HEADER ===== Measurement Date: 003-1122T23:45:00.6-07:00 and Location: Genova INFN-ANSALDO Aa1 Prototype 1 Portal
Radiation Monitor Arm1 40 centimeters double Bar1 -Aa1- Gamma-Neutron
deiscriminator PVT Comment about single bar 40 1 10 0 0 100 100 3000 400 User:
Operator ==== CENTRAL PART ==== Background 003-11-22T23:45:00.6-07:00 PT100M
5 22 200 5 Measurement Run 003-11-22T23:45:00.6-07:00 PT0.1S 5 22 200 12 0.2
==== END of File ==== PT2S 3045 100 0.1 3045 200 1.2 Average rates alarms for
Neutrons: 3 Average rates alarms for Photons: 0 Possible State: Probable NORM.
Alarm active for photons radiations: NO. Alarm active for neutron radiation: YES. Error
messages: NO. Detector status: ACTIVE.
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Readout and Data Processing Scheme
21/11/2012
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