report on the workshop for - snolab 2005...
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Report on the Workshop for
http://www.hep.umn.edu/lbcf/workshop/
Workshop Agenda
SNOLAB Workshop IV, 17 Aug 2005
SNOLAB Workshop IV, 17 Aug 2005
● Identify cross disciplinary applications for low background counting.
● Identify areas for improving low bg counting to better fill the users’ needs.
● Quantify the low background counting capabilities of sites in North America.
● Develop a means of scheduling access to counting facilities for users.
Workshop Goals
SNOLAB Workshop IV, 17 Aug 2005
● Particle/Astrophysics● Semiconductor manufacture● Biology● Archeology● Environmental Monitoring and Emergency
Response● Security
Counting Across Disciplines
SNOLAB Workshop IV, 17 Aug 2005
● Particle/Astrophysics● Semiconductor manufacture● Biology● Archeology● Environmental Monitoring and Emergency
Response● Security
Counting Across Disciplines
IC Materials Overview● High purity metals and alloys
– Cu, Al, Ta, W, Ti, Pb, Sn, Ag, Ru● Range in purity from 99.99% to
99.9999%● Alpha Activity Requirements
– 0.02 α⋅hr 1‑ ⋅cm 2‑ : early 1990’s
– 0.01 α⋅hr 1‑ ⋅cm 2‑ : late 1990’s
– 0.002 α⋅hr 1‑ ⋅cm 2‑ : 2001
– 0.0002 α⋅hr 1‑ ⋅cm 2‑ :2006
● Primary alpha emitters– 210Pb in Pb/Sn solders– U & Th
Material purity critical to reliability
Low Alpha Material Specification
0.0001
0.001
0.01
0.1
1990 1995 2000 2005 2010
Year
cts/
hr/
cm2
Synergies WorkshopB.Clark
Current Instrumentation Capability● Industry uses Gas Proportional
Counters– Area :1000 cm2 – Geometry: 2– Background– 2-3 cph optimal, 4-6 nominal– No energy spectroscopy
capability● Limited ability to identify
contamination sources● 0.002 analysis requires ~7 days
counting time for 20% RSD
Current instrumentation incapable of timely analysis
Ordela 8600
Alpha Sciences 1950
Synergies WorkshopB.Clark
Bulk Memory Test at Tower-Soudan
Synergies WorkshopJ.Wilkinson
Bulk Memory Test at Tower-Soudan
Synergies WorkshopJ.Wilkinson
SNOLAB Workshop IV, 17 Aug 2005
● Particle/Astrophysics● Semiconductor manufacture● Biology● Archeology● Environmental Monitoring and Emergency
Response● Security
Counting Across Disciplines
Production Inventory Inventory
Nuclide half-life atom/m2/sec dpm/m2 at/cm2
10Be 1,500,000 years 460 27,000 3,070,000,000,000 26Al 710,000 years 1 84 4,520,000,000 36Cl 310,000 years 11 660 15,000,000,000 81Kr 230,000 years 0.01 1 12,400,000 14C 5,730 years 25,000 1,500,000 652,000,000,000 39Ar 268 years 129 7,750 158,000,000 32Si 150 years 2 96 1,090,000 3H 12.3 years 2,500 150,000 140,000,000 22Na 2.6 years 1 52 10,200 35S 87 days 14 840 15,200 7Be 53 days 810 48,600 535,000 37Ar 35 days 8 498 3,620 33P 25.3 days 7 408 2,140 32P 14.3 days 8 486 1,440
Synergies WorkshopE.Brown
H2PO4
H2PO4
DOPH2PO4
DOPPart. P H2PO4
DOPPart. P
H2PO4
DOPPart. P
33P/32P = 0.82 33P/32P
= 1.0533P/32P = 0.95
33P/32P = 1.15
33P/32P = 1.4
33P/32P ratios in dissolved and particulate P result from the source ratio (i.e. you are what you eat) and the P
residence time.Synergies WorkshopE.Brown
32P t½ =14.3 d33P t½ = 25 d
32P/ 33P t½ = 33.4 d
Advantages:•P is a nutrient used by all living organisms.•Radioisotope half-lives relevant to biological timescales.•In-situ tracers avoid issues associated with ‘bottle effects.’•Ratio of isotopes minimizes changes due to dilution.
Disadvantages:Large sample volumes and extensive purification:
5 tons per sample!!! Several hour shiptime.
32P, 33P formed by spallation reactions in the atmosphere
Synergies WorkshopE.Brown
SNOLAB Workshop IV, 17 Aug 2005
● Particle/Astrophysics● Semiconductor manufacture● Biology● Archeology● Environmental Monitoring and Emergency Response
● Security
Counting Across Disciplines
Public Health Laboratory:Operations
● 1. environmental monitoring outside nuclear reactor sites
● 2. safe drinking water; monitor public water supplies
● 3. radiological emergency response
Synergies WorkshopJ.Brenner/J.Lorenz
Sample Collection per Facility
● River water samples – Upstream 1/month until freeze over– Downstream 1/month
River sediment 1/yr● Milk from local dairy farm 1/month● Cattle feed 1/month● Hay and grasses 1/month during growing season● Apples 1/month during growing season● Air filter samples 2/month● One residential well sample 1/month
Synergies WorkshopJ.Brenner/J.Lorenz
Methods of Analysis● Tritium
– Analysis based on EPA Method 906● Instrumentation
– Packard TRICARB-2750 Liquid scintillation counter
MDH Laboratory MDC <200 pCi/LDrinking Water MCL 20,000 pCi/LDrinking Water required activity 1,000 pCi/L46 river water samples per year (average)
Synergies WorkshopJ.Brenner/J.Lorenz
SNOLAB Workshop IV, 17 Aug 2005
● Standard analysis techniques and off the shelf counters – Well defined procedures
● Modest shielding – E.g. Pb castles in basements.
● Sensitivity is probably ok.● Major issues are throughput and speed.
Public Health
Radiation Laboratory Analysis
0
50
100
150
200
250
300
350
400
Jan
03'
Apr
03'
Jul
03'
Oct
03'
Jan
04'
Total Samples
Drinking Water
Program
Synergies WorkshopJ.Brenner/J.Lorenz
SNOLAB Workshop IV, 17 Aug 2005
● Whole Body Counting - Tom Shutt● Beta Cage - Richard Schnee
Techniques
Water shield
SS Sphere6-8 m Ø(less with low background PMTs)
scintillator
PMTs≈ 100
Sample20 cm Ø, 40 cm longPlastic - 13 Kg plasticCu - 110 Kg
• “Mini-me” version of Borexino
• Whole-body counting of sample
• 14C sets threshold near 250 KeV
A new facilityLaura Cadonati (MIT)
Synergies WorkshopT.Shutt
Synergies WorkshopR.Schnee
SNOLAB Workshop IV, 17 Aug 2005
● Europe– ILLIAS
● North America– Berkeley– Kimbalton– PNNL and LoMo– SNOLAB– Soudan
Counting Facilities
Synergies WorkshopK.Heegar for K.Lesko
Counting Facilities: Berkeley
Mine Portal
Sedimentary Host Rock
Synergies WorkshopB.Vogelaar
Counting Facilities: Kimbalton
Drive-in Access: Width 42’ (12.8 meters) Height 26’ – 105’ (8 – 32 meters) Length up to one mile
Synergies WorkshopB.Vogelaar
Counting Facilities: Kimbalton
Base facility:
•1700 ft deep• accessed by truck (or bus)• concrete pad of 42'x113’Concrete poured July 19, 2005; ready Sept 2005
PLAN:• water, septic, 50kW electric• internet• 20'x40' assembly hall• 12'x40' office trailer• 8'x24' NRL lab• unallocated (~ 40'x40')• 30 minutes from VT to the mine• 15 minutes from the surface
Synergies WorkshopB.Vogelaar
Counting Facilities: Kimbalton
Material Screening
HPGe detctors, like these at Gran Sasso
Prefabricated laboratories can be driven in.
Synergies WorkshopB.Vogelaar
Counting Facilities: Kimbalton
Synergies WorkshopT.Hossback
Counting Facilities: LoMo
Synergies WorkshopT.Hossback
Counting Facilities: LoMo
Synergies WorkshopT.Hossback
Counting Facilities: WIPP
Synergies WorkshopT.Hossback
Counting Facilities: WIPP
Low background Screening and Prototyping Facility at the Soudan Underground Lab
40’ x 35’ x 100’ cavern surrounded by a 99% efficient active muon veto
SOLO HPGeJim Reeves: Cu Electroforming SBIR + Cu screening detector (microBq/kg) Diode M (35%)
Twin (75%)UF detector (100%)
Synergies WorkshopP.Cushman
Counting Facilities: Soudan
Low background Screening and Prototyping Facility at the Soudan Underground Lab
CDMS offices
CDMS Aux Clean RoomBFand SiLi detector
Veto shield repaired last summer DAQ: location & time stamp for each muon Synergies Workshop
P.Cushman
Counting Facilities: Soudan
Ante-room Ante-room
Multi-purpose clean room
Clean room over tank
Water ports with crane
Electro form
40 ft
Upper mezzanine above tank top
Use
r sh
ield
ing
Clean room over tank
anteroomClean room
Clean room
Water tankShieldedbays
mezzanine
anteroom
radon scrubbing plenum.
stairs
current mezzanine
Muon veto shield
Muon veto shield
Mu
on
vet
o s
hie
ld
Mu
on
veto sh
ield
100 ft
Drawings and Design Consultation: Short Elliott Henderson Engineering, Inc
Synergies WorkshopP.Cushman
Counting Facilities: Soudan
SNOLAB Workshop IV, 17 Aug 2005
● Location– http://www.hep.umn.edu/lbcf/integration/index.html
● Intended to be an access site to the low background counting facilities (primarily in North America).
● Will list the capabilities of the facilities● Eventually allow scheduling of samples.● Contact
– P. Cushman: [email protected]
Integration Website
SNOLAB Workshop IV, 17 Aug 2005
● Particle Physics Experiments want
– Counting Speed– Increased Sensitivity
● Other disciplines want
– Mostly Counting Speed– But also in some cases increased Sensitivity
● Various plans to expand the underground screening facilities (Soudan, Kimbalton)
● Effort to develop an integrated low background counting infrastructure (Integration Website).
● However, presently there does not appear to be excess capacity in North America.
Summary
End