![Page 1: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/1.jpg)
Anders Ringbom, Anders Axelsson, Mattias Aldener, Tomas Fritioff, Johan Kastlander, Anders Mörtsell
Swedish Defence Research Agency (FOI)
SAUNA III – a major upgrade
![Page 2: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/2.jpg)
Outline
• Scientific reasons to develop the noble gas systems in IMS.
• SAUNA III development:
• Collection and processing
• Detector
• Software
• Summary and Conclusions
![Page 3: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/3.jpg)
Why do we need to develop the NG systems further?
Practical/economic reasons:
● Improve reliability, maintainability and user friendliness
Scientific reasons:
● The PrepCom requirements, set 20 years ago, need an update● Based on the technology available at the time● Background not known at the time● Only based on detection capability
● Need to approach the problem with respect to network verification capability● What is the unique NG signal, and how do we increase our capability to
detect it using the current 40 station network?
![Page 4: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/4.jpg)
Better sensitivity is not the whole story
Current systems, 1kt , 100% release
Maximum achievable with current site configuration. 60% of explosions detected within one week (background not included).Will not improve with more sensitive systems*.
*FOI talk in session T4.1: “A novel approach to assess the verification capability of the network”
![Page 5: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/5.jpg)
The signals we are looking for...
Isotope combination Network background* (95% conf. level)
Network background* (99% conf. level)
133Xe, 133mXe, and 135Xe 0.27% 0.07%133Xe and 135Xe 3.2% 0.98%133Xe and 133mXe 2.7% 0.67%133Xe 35% 28%133Xe and 131mXe 4.4% 1.9%
● Ratios and ATM compatible with time zero given by seismic signal● Other sources excluded
* Based on > 80 000 samples. See FOI poster:“The global radioxenon background – an update” (T2.4).
DPRK1 SAUNA measurement 2006DPRK1 IMS measurement 2006DPRK3 IMS measurement 2013
![Page 6: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/6.jpg)
Potential improvements
Detection capability:
Relevant for all isotopes at remote stations with low background. Important to increase detection capability for 133mXe everywhere.
Measurement uncertainty:
Important for ratio interpretation. Small uncertainties increase ability to exclude scenarios. Ratio quantification increasingly risky close to detection limit
Time resolution:
Higher time resolution improves source location. Increases ability to distinguish explosion signal from background.
![Page 7: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/7.jpg)
Measurement precision is crucial for discrimination
1h24h
~6 years of data (USX75), 4228 samples, 99% conf. level, 30/4228 = 0.7% remaining
Containment time:
Kalinowski 2010 line
![Page 8: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/8.jpg)
SAUNA: 1999 - 2015 SAUNA-OSI-2014
1990-1999: “pre-SAUNA” NG network in Sweden
1999-2000: The Freiburg INGE experiment
SAUNA I - 1999
SAUNA I atSpitsbergen2000-2004
SAUNA II - 2004
Mobile sampling -2006
SAUNA III - 2018
![Page 9: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/9.jpg)
SAUNA III main specifications
SAUNA II SAUNA III
Carrier gas Helium Nitrogen
Air volume/sample 16 m3 36 m3
Stable Xe volume in cell 1.2 ml 3.0 ml
Collection time 12 h 6 h
Air flow 22 SLM 100 SLM
MDC 133Xe / sample, 2 cells 0.3 mBq/m3 ~0.2 mBq/m3
MDC 133Xe / sample, 4 cells - ~0.15 mBq/m3
![Page 10: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/10.jpg)
Sampling oven
Sampling oven
Pump
PLC
XPU
Process ovens
GC
SoH
Archive
PCPC
UPS
SAUNA II
He Detectors
![Page 11: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/11.jpg)
Pumpand PSA
PLC
XPU
POV
GC
SoH
Archive
PCPC
UPS
SAUNA III
Sampling oven
Sampling oven
N Detectors
![Page 12: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/12.jpg)
Sampling and processing*
Pump PSA Sampling
ovenProcess
oven GC
Goal: x10 sXe enrichment, 95% yield
See FOI poster: “Studies of increased air collection capability for SAUNA III”
![Page 13: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/13.jpg)
Sampling and processing
One oven removed
New GC(OSI-type)Sample re-quantifiedafter activity measurement
Pump PSA Sampling
ovenProcess
oven GC
OSI-typesamplingoven :
![Page 14: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/14.jpg)
Beta detector*
● Nitrogen as carrier gas + larger sXe volume => straggling● GEANT calculations to optimize design● Refinement of polishing and coating technique● Goal: all produced cells should have an energy resolution
< 35 keV @ 129 keV electron energy● Four different designs will be tested. First cells produced.
“polished”ΔE=31 keV
“rough”ΔE=54 keV
* See FOI poster “SAUNA III detector development”
electron energy (keV)
![Page 15: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/15.jpg)
Beta detector
Teflon reflectorΔE=35 keV
New reflectormaterialΔE=28 keV
Example of test resultswith in-house manufacturedcells (SAUNA II geometry).
Achieved memory effect < 0.1 %.
![Page 16: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/16.jpg)
Active energy drift control
● Energy scale drift ~1% / °C for NaI● Other sources for energy drift: PM-tubes, HV supply, …● Studies of drift performed● Solution using active compensation will be designed -
most likely the QC source will be used for this purpose.
![Page 17: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/17.jpg)
New operational software
● All user functionality in one software with one GUI
● The system operated as a state machine with different modes
● Diagnostic mode● Calibration mode● Manual mode● Routine mode
![Page 18: SAUNA III – a major upgradeSAUNA III main specifications SAUNA II SAUNA III Carrier gas Helium Nitrogen Air volume/sample 16 m3 36 m3 Stable Xe volume in cell 1.2 ml 3.0 ml Collection](https://reader036.vdocuments.us/reader036/viewer/2022062507/5fdddb03a3806b2662565a1a/html5/thumbnails/18.jpg)
Summary and conclusions
● In order to achieve better verification capability using the 40-station IMS NG network, increased measurement precision and time resolution is needed.
● The SAUNA III project address both issues.● The capacity of the sampling system will increase four-fold compared
to SAUNA II.● Nitrogen will be used as carrier gas.● The beta detector will be further developed to improve energy resolution.● Active adjustment of detector energy drift● New operator software is developed, including one single GUI and new
operational modes.● The design is handed over from FOI to manufacturer in December 2016.● According to manufacturer, production can start in 2018.
● The SAUNA concept - operation at ambient temperature - remains.