isac science forum - triumf science... · 2009. 3. 18. · isac science forum: wednesday, august...
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ISAC Science Forum: Wednesday, August 20th, 2008 at 15:15 in the ISAC-II Conference Room The schedule for the meeting will be as follows: * reports on finished/on-going and up-coming experiment: * EDM (Mike Hayden -SFU) * beta-NMR (Gerald Morris) * TRINAT (John Behr) * status actinide test (Colin Morton) * fall schedule discussion (G. Ball) * supernanogan and CSB installation and commissioning plan (F. Ames) * aob
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Gordon Ball,1 John Behr,1 Tim Chupp,2 Celia Cunningham,2 Greg Demand,3
Martin Djongolov,1 Paul Finley,3 Adam Garnsworthy,1 Paul Garrette,3 Katie Green,3
Greg Hackman,1Mike Hayden,4 Carolyn Kierans,1,4 Jamie Kilkenny,1
Wolfgang Lorenzon,2Matthew Pearson,1 Tim Raben,2 Evan Rand,3
Chandana Sumithrarachchi,3 Carl Svensson,3 Eric Tardiff,2 Smarajit Tirambak,1
Scott Williams,1 Jan Zirnstein2
1TRIUMF2University of Michigan3University of Guelph
4Simon Fraser University
S929 Rn Electric Dipole Moment
Search at ISAC: Progress Report
Hayden / ISAC Science Forum / Aug 20, 2008
Spokesmen: T. Chupp and C. Svensson
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Requested: 8 shifts of 121Cs & 123Cs with intensities ~106 s-1
(decay to 121Xe,123Xe)
Basis: beams of 1.3 × 106 s-1 and 5.6 × 107 s-1 previously
demonstrated at ISAC for 121Cs & 123Cs from Ta
production targets and surface ion sources
Objective: collect, manipulate, and polarize 121Xe & 123Xe
(surrogates for Rn isotopes)
Received: 123gCs: 1.2×106 s-1 & 123mCs: 6.2×104 s-1
→ 123Xe: τ½ ~ 2 hrs, J=1/2
121gCs: 7.8×103 s-1 & 121mCs: 6.2×104 s-1 Low!
→ 121Xe: τ½ ~ 40 min, J=5/2
Hayden / ISAC Science Forum / Aug 20, 2008
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REDM
Rn EDM location
at ISAC-I
Goal#1: commission ILE1 beamline extension to RnEDM
Hayden / ISAC Science Forum / Aug 20, 2008
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implant Cs
(decays to Xe)
heat foil to
release Xe and …
… cryopump Xe
to coldfinger
1
2
3
4 warm coldfinger
and ‘push’ into
cell using N2 gas
5 close valve, and start
next collection cycle
Goal#2: test and refine collection & transfer of Xe
Hayden / ISAC Science Forum / Aug 20, 2008
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Hayden / ISAC Science Forum / Aug 20, 2008
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Hayden / ISAC Science Forum / Aug 20, 2008
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Transfer Efficiency(Coldfinger and Push)
• Transfer Xe by
cryopumping directly
into cell
• Warm up cell and
cryopump Xe to
coldfinger
• Push Xe back into cell
using N2 gas
Preliminary
Preliminary
Preliminary
Preliminary
Hayden / ISAC Science Forum / Aug 20, 2008
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Study Xe Adsorption to Surfaces
0.0085 0.0090 0.0095 0.0100 0.0105 0.0110 0.01150.01
0.1
1
123Xe on Stainless Steel
(Tcell/T
CF)1/2 RCF/R
cell
1/T (1/K)
preliminary result: EB=2.75(15) x 10
3 K
Preliminary
Preliminary
Tcell = 77K
cell
coldfingerTCF > Tcell
HPGe
(Rcell)
HPGe
(RCF)
Hayden / ISAC Science Forum / Aug 20, 2008
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Hayden / ISAC Science Forum / Aug 20, 2008
Goal#3: incorporate spin-exchange optical pumping &
polarization of 121Xe; measure γ-ray emission anisotropies
cell B, M
HPGe
HPGe
Laser (on/off 10 min period)
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Hayden / ISAC Science Forum / Aug 20, 2008
Started with 123Xe because of low 121Xe rates (~ 18hrs)
Finished run with 121Xe (~ 12 hrs)
Goal#3: incorporate spin-exchange optical pumping &
polarization of 121Xe; measure γ-ray emission anisotropies
Entire sequence (cool coldfinger, heat foil, collect Xe,
warm coldfinger, push into cell, start optical pumping)
accomplished in under 10 minutes
time →off
on
off
on
off
on
offγasymmetry
Hints of γ-ray asymmetries for 121Xe, but not yet conclusive
β+-assymetry for 123Xe ?
Detailed analyses underway
Preliminary
Preliminary
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Hayden / ISAC Science Forum / Aug 20, 2008
Summary
beamline commissioning
efficient and rapid transfer of noble gas to cell
polarize and detect asymmetries?
statistics limited by 121Cs
production rate
Next Steps (using Cs →Xe)
study polarization buildup and decay
detect free precession signal
optimize design for sensitivity to β+ asymmetry
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S1127 Search for Exotic Massive Particles in decay oftrapped isomers
Search for anything massive emittedfrom nuclear transition, independentof interaction in detector or lifetime• Statistical sensitivity ∼ 10 � 6branch per day of counting
photo−ionizing
778 nm
E= 0 V/cm E= 3 V/cm
6 cm
e−+Rb
γ
18.025.0
6− 1.0 m
2−
Rb86
556 keV
Behr for Kong, Chatwin-Davies, Gorelov, Murray, Pearson
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Neutral daughter atom has 1.9 eV kinetic energy:photoionization scheme
Thibault PRC 1981: we agree withtheir isotope shifts in trappingtransitions :)
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< 1250nm
5P
5D
Rb I5S
778 nm
778 nm
Behr for Kong, Chatwin-Davies, Gorelov, Murray, Pearson
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We need the unknown S to D transition of the 86Rbground state
• Yield insufficient to hunt fortransition on the decaying atoms(estimate ∼ 1/minute onresonance)• We realized (9 p.m. Tuesday) wecould trap the 18-day 86gRb andmeasure the 2-photon yield on thetrapped atoms• Then we took several hours ofdata on 86mRb decay with thelasers fixed at that frequency. Wemay find in the analysis that wehave demonstrated our technique.
Behr for Kong, Chatwin-Davies, Gorelov, Murray, Pearson
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summaries
• Trapped several 1,000 atoms 86mRbTrapped several 10,000 atoms 86gRb and measured neededisotope shift in S to D two-photon transitionTook 3 hours data in final night in full experimental mode withfrequencies optimized.• Yield of 86mRb was 6x106/sec for most of run.Yield declined 20% yesterday after one proton trip, thendropped linearly to 3x10**6/sec at end of run• Those of us who are here and those of us who are sleeping(like Tao Kong, Ph.D. student) thank everyone for the extra dayof beam where we made critical progress
Behr for Kong, Chatwin-Davies, Gorelov, Murray, Pearson
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Actinide Target Development – ISAC Science Forum, August 20, 2008 A.C. Morton
The plan:
• First test run with a UOx target • Limited currents:
o ~1 A o 300 A•hrs total – total potential radiological hazard
comparable to 30,000 A•hrs on Ta or Nb
• Originally scheduled to start today; delayed until next week – license and entrance module
The run:
• Stage 1: 0—100 A•hrs (~8 shifts) o No extraction
o Rad. safety measurements at 50, 100 A•hrs • Stage 2: 100—300 A•hrs (~16 shifts)
o Extraction and delivery to yield station
o Yield measurements of selected alkalis o Rad. safety measurements at 150, 300 A•hrs
• Need CNSC “concurrence” to proceed to Stage 2
Status:
• Monitoring and controls:
o Radiation monitoring upgrades completed o Some controls work still in progress
• Target:
o Entrance module repaired and replaced o TM1 to fly to ITW August 21
• Licence:
o Hearing (in Ottawa) August 22 [Incorrectly reported as “tomorrow” in the meeting – ACM] – not public
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Status and Commissioning Planfor the
ISAC Charge State Breeder (CSB)
Friedhelm Ames, TRIUMF, August 20, 2008
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B(m0)
B(m(Emax))
B(z)
z
1+ n+
rf
B)E(m
qcrf =ω=ω
PHOENIX ECR source:
3cm1210...1110en
keV730maxET25.1maxB
T52.0)0m(BGHz5.14rf
−=
=⇒=
=⇒=ν
Electron Cyclotron Resonance Ion Source (ECRIS)
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charge breeder results from the test stand
Measurements with ions from standard ISAC ion sources
Element Mass
Charge state with maximum efficiency (A/Q)
Efficiency (%)
rise time (90%) for charge state with maximum efficiency (ms)
1+ ion source
Ar
Kr
Xe
K
Rb
Cs
ECR1025.58+ (5)40
84 ECR
129
401
39
6.3
85/87
12+ (7)
17+ (7.6) 432
9+ (4.3)
13+ (6.5)
4.8
2.1
133 20+ (6.7)
3
3.5
230
300
ECR
surface
surface
surface + testsource
•emittance of Csn+ measured < 20 π mm mrad @ 15 kV
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installation in ISAC mass separator room
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Statusmechanical installation finishedservices installation finishedvacuum finishedcontrols not finished scheduled end of Sept.rf not tested scheduled end of Sept.
August 14, first test on the injection of ions from ISAC into the CSB failedinvestigation of reasons is going on
PlanComissioning of charge breeding with Cs test ion sourceNew injection test from ISAC scheduled for October 30
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End of shut-down 2008
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Status and Commissioning Planfor the
OLIS SUPERNANOGAN ECR ion source
Friedhelm Ames, TRIUMF, August 20, 2008
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SUPERNANOGAN ECR ion source
permanent magnet6-14.5 GHzsputtering targets and ovens for nongaseous elements
should provide stable highly charged ion beamsas pilot beams for CSB or directly for experiments
ION H+ He+ He2+ C4+ O6+ Ar4+ Ar8+ Ar9+ Ar11+ Xe25+ Au30+
I eµA 1000 1000 500 200 200 300 200 80 30 10 1
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Implementation in existing OLIS cage
microwave source
surface source
SUPERNANOGAN
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gas inlet and control system
source cart in OLIS HV cage
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Schedule for final installation and commissioning (draft)
ISAC Science Forum_Aug 20 2008.docEDM_M. Hayden.pdfTRINAT_J. Behr.pdfActinide Test_C. Morton.pdfCSB_F. Ames.pdf
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