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CANADA’S NATIONAL LABORATORY FOR PARTICLE AND NUCLEAR PHYSICS. Owned and operated as a joint venture by a consortium of Canadian universities via a contribution through the National Research Council Canada. - PowerPoint PPT Presentation
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CANADA’S NATIONAL LABORATORY FOR PARTICLE AND NUCLEAR PHYSICS
Owned and operated as a joint venture by a consortium of Canadian universities
via a contribution through the National Research Council Canada
LABORATOIRE NATIONAL CANADIEN POUR LA RECHERCHE EN PHYSIQUE NUCLÉAIRE ET EN PHYSIQUE DES PARTICULES
Propriété d’un consortium d’universités canadiennes, géré en co-entreprise à partir d’une contribution administrée par le Conseil national de recherches Canada
OUTLINEALPHA introduction New Results with Si vertex detectorDevelopment for Spectroscopy TRIUMF Review on ALPHA
Makoto C. Fujiwara, ACOT, March 13, 2009
Project ALPHA:Antihydrogen Laser Physics
Apparatus
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MAKOTO C. FUJIWARA
ALPHA Antihydrogen Project
• ALPHA: Canadian funding in Jan 2006First beam at CERN in July 2006
• May 2007, first ALPHA presentation at ACOT
• April 2008, TRIUMF Review on ALPHA (see attached report)
• Increasingly strong university participation– UBC, Calgary, Simon Fraser, York + Montreal (5 graduate
students) – Rob Thompson: leading the effort for U. Calgary to join TRIUMF
as Associate Member
• ALPHA-Canada: significant force in ALPHA– Responsible for much of subatomic physics aspects– Leading the development of antihydrogen spectroscopy
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MAKOTO C. FUJIWARA
Motivations: Simple and Clear
• Atomic hydrogen: one of best studied systems
• Comparison with Hbar (antihydrogen): a “must do”– CPT symmetry, Gravity
• Stable trapping of Hbar:– Technical bottleneck for symmetry
tests– Opening up new field: Antimatter
Science
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MAKOTO C. FUJIWARA
Trapping Antihydrogen
Na-22Na-22
ee++ Production Production (MeV)(MeV)
ModerationModeration
Accumulation (eVAccumulation (eV)
Cooling ( ~ meV)Cooling ( ~ meV)
108 e+
ADADp- Production
(GeV)
Deceleration (MeV)Trapping (keV)
Cooling (~ meV)
104 p-
1010-12-12 1010-9-9
Superimpose Magnetic Trap
U B
Easy, eh?
Cold Hbar Production: ATHENA (2002) + Neutral Trap
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MAKOTO C. FUJIWARA
Challenges in Anti-Atom Trapping
• Plasma stability – Normally axial symmetry
assures plasma confinement [O’Neil’s confinement theorem]
– Magnetic trap field strongly breaks the symmetry
108 e+104 p-
• Antimatter atoms – Can’t buy an
antihydrogen gas bottle!
– Standard atom trap techniques do not apply
– Need to invent new methods
“Pushing new physics boundaries in plasma, atomic and other fields”TRIUMF Review Report
• Atomic formation processes– Not completely understoode.g. MCF et al, PRL 101, 053401
(2008)
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MAKOTO C. FUJIWARA
Challenges in Anti-Atom Trapping
• Plasma stability – Normally axial symmetry
assures plasma confinement [O’Neil’s confinement theorem]
– Magnetic trap field strongly breaks the symmetry
108 e+104 p-
• Antimatter atoms – Can’t buy an antihydrogen
gas bottle!• Must be synthesized in situ
from pbar and e+ plasmas• Compatibility of Penning trap
and neutral trap
– Standard atom trap techniques do not apply
• No anti-Teflon walls• No convenient lasers• No collisional cooling
“Pushing new physics boundaries in plasma, atomic and other fields”TRIUMF Review Report
• Atomic formation processes– Not completely understoode.g. MCF et al, PRL 101, 053401
(2008)
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MAKOTO C. FUJIWARA
ALPHA: Before and After
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MAKOTO C. FUJIWARA
What we have achieved so far
• Design, Construction, commissioning: NIM (2006)
• Trapping of e-, e+, pbars in Penning traps• Electron cooling of pbars• Hbar production at 3T (like ATHENA)• Pbar, e+ confinement in Octupole field: PRL (2007)• Hbar production at 1T: J. Phys. B (2008)• Plasma diagnosis in Octupole: Phys. Plasmas (2008)
• Pbar plasma radial manipulations: PRL (2008) • Commissioning of 2/3 Si detector• Observation of ballistic transport: in preparation for Phys.
Lett. B• Discovery of zero-rotation bounce resonance: submitted to
PRL• Production of Hbars in magnetic trap: submitted to PRL• First search for trapped antihydrogen: in preparation • Proposal for realistic schemes for microwave
spectroscopy
Reported atTRIUMF ReviewApril 2008
New since May 2008
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MAKOTO C. FUJIWARA
New Progress in 2008:ALPHA Si Vertex Detector
Liverpool, TRIUMF +Calgary (Richard Hydomako),
UBC (Sarah Seif El Nasr)York (Hasan Malik, Scott Menary)
Montreal (J.P. Martin)
ALPHA-Canada responsible for Basic design, Readout (30k ch), DAQ, Monte Carlo,
Reconstruction, Analysis and Operation of the Detector
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MAKOTO C. FUJIWARA
Antihydrogen Detection and Diagnosis
Trapped Hbar detection: Create Hbars in a neutral trap Clear all the charged particles Release the trap in ~20 msec Look for annihilations on the walls
First measurements will be statistics limited Need best event characterizations, background
rejections Position sensitive detection of antihydrogen
annihilations 3D annihilation imaging: unique tool to study
plasmas
Si: 3 layers 30k channel
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MAKOTO C. FUJIWARA
Physics with Si tracker 1: Ballistic loss
• “Ballistic” pbar loss in octupole field due to symmetry breaking
• Unique annihilation signatures – Enhanced at trap edges
– 4 hot spots at each end • Background for Hbar detection
Cross sectional images at trap edges
Axial annihilation distribution
Calculated field lines in neutral trap
Sarah Seif El Nasr, M.Sc. Thesis (UBC)
In prep. for Phys. Lett. B (2009)
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MAKOTO C. FUJIWARA
Result2: New plasma transport mechanism
• Non-harmonicity of electrostatic potentials• Symmetry breaking multipole magnetic fields
Zero-rotation bounce resonance
Si vertex images
Data SimulationSubmitted to PRL (2009)
Simulated particle orbits
Gaining quantitative understanding of new plasma processes
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MAKOTO C. FUJIWARA
Result 3: Hbar production in anti-atom trap:
• Efficient Hbar production in neutral trap, detected via Si
• Important milestone for Hbar trapping
• Started search for trapped Hbars
Hbar yields vs. trap depths
Hbar images via Si tracker
Submitted to Phys. Rev. Lett. (2009)
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MAKOTO C. FUJIWARA
Towards Antihydrogen Spectroscopy
Walter Hardy (UBC)Mike Hayden, Mohammad Dehghani
(SFU)Rob Thompson, Tim Friesen
(Calgary)[David Jones, UBC]
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MAKOTO C. FUJIWARA
Wave Spectroscopy: Hardy & Hayden
1. Positron Spin Resonance – Pulsed W at ~20
GHz trapped un-trapped
– Look for annihilations– Can start with a few
atoms
0.0 0.2 0.4 0.6 0.8 1.0
B0 (T)
Ene
rgy
(GH
z) 15
-15
ah
(Anti)hydrogen energy diagram
20 GHz
trapped states
un-trapped states
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MAKOTO C. FUJIWARA
W Spectroscopy: Hardy & Hayden
1. Positron Spin Resonance – Pulsesd W at ~20 GHz
trapped un-trapped– Look for annihilations– Can start with a few atoms
2. NMR (pbar spin flip)– 655 MHz at magic 0.65T
turning point: insensitive to 1st order B inhomogeneity
– Double resonance w/ PSR
0.0 0.2 0.4 0.6 0.8 1.0
B0 (T)
Ene
rgy
(GH
z) 15
-15
ah
(Anti)hydrogen energy diagram
20 GHz
655 MHz
trapped states
un-trapped states
ALPHA has accepted Wavefor 1st spectroscopy attempt
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MAKOTO C. FUJIWARA
Microwave Tests at CERN & SFUhorn focusing
reflector
Loss > 10 dB
W. Hardy et al, June 2008 at CERN
Plasma compatible resonator
M. Hayden et al. 2008
4 cm
SFU prototype f0: 600-800 MHz Q: 100-300
opposed finger-like structures
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MAKOTO C. FUJIWARA
ALPHA Review & Collaboration Meeting
April 4-8, 2008, TRIUMF ~30 participants (9 institutes, incl. 4 Canadian)
Reviewers : G. Gwinner (Manitoba), M. Lefebvre (UVic), M. Romalis (Princeton) “It is fair to say that without Alpha Canada’s contribution, the
experiment would not be operating today.”“ Continued support of TRIUMF in the near future is crucial to reap the
rewards of previous investment.”
“[In the spectroscopy phase] It will still be advantageous to focus the university efforts through TRIUMF leadership.”
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MAKOTO C. FUJIWARA
Extra Slides
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MAKOTO C. FUJIWARA
2009 Run: June 8 to Nov 23 (longer due to LHC?)
– Detector/Software• Full Si detector commissioning• Improved Data Acquisition• Improvements in tracking and analysis codes• Better understand detector backgrounds
– Trapping • Hbar trapping attempts with established
schemes• Colder plasmas with new cooling schemes
– Spectroscopy• Development of efficient injection of 30 GHz
W
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MAKOTO C. FUJIWARA
University of Aarhus: G. Andersen, P.D. Bowe, J.S. Hangst
RIKEN: D. Miranda, Y. Yamazaki
Federal University of Rio de Janeiro: C.L. Cesar,
University of Tokyo: R.S. Hayano
University of Wales, Swansea: E. Butler, M. Charlton, A. Humphries, N. Madsen
L. V. Jørgensen, M. Jenkins, D.P. van der Werf
Auburn University: F. Robicheaux
University of California, Berkeley: W. Bertsche, S. Chapman, J. Fajans, A. Povilus, J. Wurtele
Nuclear Research Centre, Negev, Israel: E. Sarid
University of Liverpool: P. Nolan, P. Pusa
University of University of British ColumbiaBritish Columbia:: S. Seif El Nasr, D.J. Jones, WS. Seif El Nasr, D.J. Jones, W..N. Hardy*N. Hardy*
University of CalgaryUniversity of Calgary:: T. Friesen, R. Hydomako,T. Friesen, R. Hydomako, R.I. Thompson*R.I. Thompson*
UniversitéUniversité de de MontréalMontréal: J.-P. Martin*: J.-P. Martin*
Simon Fraser UniversitySimon Fraser University: M. Dehghani, M. Hayden*: M. Dehghani, M. Hayden*
TRIUMFTRIUMF: P. Amaudruz*, M. Barnes, M.C. Fujiwara*, D.R. Gill*, : P. Amaudruz*, M. Barnes, M.C. Fujiwara*, D.R. Gill*,
L. Kurchaninov*, K. Olchanski*, A. Olin*, J. Storey + Professional Support**L. Kurchaninov*, K. Olchanski*, A. Olin*, J. Storey + Professional Support**
York UniversityYork University: H. Malik, S. Menary*: H. Malik, S. Menary** Active faculty/staff in present phase* Active faculty/staff in present phase
**P. Bennett, D. Bishop, R. Bula, S. Chan, B. Evans, T. Howland, K. Langton, J. Nelson, D. Rowbotham, P. Vincent +**P. Bennett, D. Bishop, R. Bula, S. Chan, B. Evans, T. Howland, K. Langton, J. Nelson, D. Rowbotham, P. Vincent +
Undergrad Students: W. Lai, L. Wasilenko, C. KolbeckUndergrad Students: W. Lai, L. Wasilenko, C. Kolbeck
Project ALPHA CollaborationProject ALPHA Collaboration
ALPHA-CanadaALPHA-Canada
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MAKOTO C. FUJIWARA
ALPHA Publications
1. 'A Magnetic Trap for Antihydrogen Confinement' Nucl. Instr. Meth. Phys. Res. A 566, 746 (2006)
2. 'Antimatter Plasmas in a Multipole Trap for Antihydrogen'Phys. Rev. Lett. 98, 023402 (2007)
3. 'Production of Antihydrogen at Reduced Magnetic Field for Anti-atom Trapping'J. Phys. B: At. Mol. Opt. Phys. 41, 011001 (2008)
4. 'A Novel Antiproton Radial Diagnostic Based on Octupole Indused Ballistic Loss'Phys. Plasmas 15, 032107 (2008)
5. 'Critical Loss Radius in a Penning Trap Subject to Multipole Fields'Phys. Plasmas 15, 032108 (2008)
6. 'Compression of Antiproton Clouds for Antihydrogen Trapping'Phys. Rev. Lett 100, 203401 (2008)
7. Antihydrogen Formation Dynamics in and Anti-atom trap, submitted to Phys. Rev. Lett. (2009)
8. Magnetic multipole induced zero-rotation frequency bounce-resonat loss in a Penning-Malmberg trap used for antihydrogen trapping submitted to Phys. Rev. Lett. (2009)
9. 'Temporally Controlled Modulation of Antihydrogen Production and the Temperature Scaling of Antiproton-Positron Recombination'M. C. Fujiwara et al. (ATHENA data analysis) Phys. Rev. Lett. 101, 053401 (2008)
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MAKOTO C. FUJIWARA
Canadian Contributions
1. Beam monitors2. External Scintillator3. Internal Scintillator4. MIDAS DAQ System5. On-line/Off-line Software6. Si vertex detector design & simulations7. Si readout electronics 8. Trap control electronics9. Building Experiment 10.Running Experiment 11.Physics Analysis 12.Developments towards spectroscopy
1. Beam monitors2. External Scintillator3. Internal Scintillator4. MIDAS DAQ System5. On-line/Off-line Software6. Si vertex detector design & simulations7. Si readout electronics 8. Trap control electronics9. Building Experiment 10.Running Experiment 11.Physics Analysis 12.Developments towards spectroscopy
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MAKOTO C. FUJIWARA
Building ALPHA at CERN
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MAKOTO C. FUJIWARA
ALPHA Potential Sensitivity (model dep’t!)
CPTVn
nmE
1
~
GeVPossible CPTV shift (Pospelov)
Small absolute energy E probes high energy
scale
For n=1, m=1 GeV, CPTV = MPl ~ 1019 GeV
ECPT ~ 10-19 GeV (~10 kHz in frequency)
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MAKOTO C. FUJIWARA
ALPHA Antihydrogen Apparatus
Mixing trap(1T)
e+
Mixing electrostatic potential
Octupole magnet
Si tracker
antiproton trap(3T)
pbar
Superimpose Penning Trap and Magnetic Trap
U B
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MAKOTO C. FUJIWARA
ALPHA Challenges
Characteristic energy scales:– Plasma energy: space
charge (∝ener2 ) ≈ 10 eV– Neutral trap depth:
(B) ≈ 0.1 meV– Need to bridge 105
disparity in energy scales
Careful optimization of plasma processes
Sensitive detection system
Understanding plasma
Optimizations in particle moving and shaking: – ~40 potentials, time scale,
particle numbers etc.– Not a fundamental
limitation, but takes time!– Largely systematic trial
and error: much of 5-6 months beam time spent on this
Antihydrogen quantum states:– Formation process still not
completely understood– Need ground state for
spectroscopy “Pushing new physics boundaries in plasma, atomic and other fields”
TRIUMF Review Report
28
MAKOTO C. FUJIWARA
ALPHA Challenges
• Plasma stability – Normally axial symmetry
assures plasma confinement [O’Neil’s confinement theorem: 1980]
– Magnetic trap field strongly breaks the symmetry
r c 2
e
1
2i
N
iBP
Radial B field
Octupole vs Quadrupole
• Use Octupole instead of Quadrupole
• Perturbation near axis much reduced
108 e+104 p-
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MAKOTO C. FUJIWARA
Plasma confinement in Octupole trap
• Antiprotons and positrons in 1.2 T octupole field
• Number of particles measured as a function of storage time
• Demonstrate compatibility of Charged and neutral trap
Phys. Rev. Lett. 98, 023402 (2007)Radial B field : Octupole vs
Quadrupole
• Use Octupole instead of Quadrupole • Perturbation near axis much reduced
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MAKOTO C. FUJIWARA
More ALPHA Physics Results• Hbar production in 1T• New plasma radial diagnosis• Obtained with APD readout
Scintillator Arrays operated at 1 to 3T
• Developed at TRIUMF/UBC due to Si detector delays
J. Phys. B 41, 011001 (2008) Fast Track
Phys. Plasmas 15, 032107 (2008)
Scot Menary (York)R&D for new beam detector
CVD Diamond
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MAKOTO C. FUJIWARA
Antiproton Plasma Radial Compression
• Plasma radial control important
– Recall E ∝ener2 • External rotating RF
field exerts torque on plasma radial compression
• What’s new?– Normally need
coolant – Use electrons as a
coolant
Phys. Rev. Lett. 100, 203401 (May 2008)
Multi-channel plate imaging
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MAKOTO C. FUJIWARA
Si Tracker Construction
• Summer 2005 Basic design at TRIUMF Compatible with traps
• Oct-Nov 20076 modules in situ test
• June-Nov 200838 module out of 60 commissioned (only 20,000 channel!)
• Spring 2009Full detector (30,000ch)will be installed
Si sensors built at Liverpool
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MAKOTO C. FUJIWARA
Read Out System
• Custom made modules• TRIUMF-Montreal
48 channel FADCs• Level 1.5 triggering
capability with FPGA• Much improvement over
ATHENA in performance & cost
• Similar to Belle system
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MAKOTO C. FUJIWARA
AD Future at CERN
CERN Research Board, December 2008• Antiproton Decelerator: operational until
2017• New antimatter gravity experiment AEGIS
just have been approved
Other high intensity hadron facilities • Proposal for low energy pbars at GSI/FAIR• LOI at J-PARC, Fermilab
Mike Hayden
PSR Lineshapes and spectral resolution
16 18 20 22
b-c a-d
f (GHz)
10-7 10-6 10-5 10-410-5
10-4
10-3
f bc /
f bc
(s)RF pulse length (s)
limited by radial homogeneity of field
limited by spectral
width of RF pulse
atoms move significant distances during
no resolution improvement forpulses longer than ~10s
Mike Hayden
10-7 10-6 10-5 10-410-5
10-4
10-3
10-2
f cd /
f cd
(s)
NMR lineshape and spectral resolution
RF pulse length (s)
limited by spectral
width of RF pulse
B0 = 1.01B′
B0 = B′
atoms move significant distances during
coherent atom-field interactions limited by transit time to ~ 100s 654.0 654.2 654.4 654.6 654.8 655.0
B0= B'
B0> B'B
0< B'
c-d transition
f (GHz)
fcd at B0=B′
Mike Hayden
10-5 10-4101
102
103
104
Pow
er (
W)
Pulse Duration (s)
Power Requirement
RF pulse length (s)
Pow
er (
W)
c-d transitionEjection
probabilities of a
few percent/pulsefield homogeneity limit
transit-time limit
Estimates for power required to induce spin flip; based on K/Ka-band Wave loss measurement and calibration of B1 in UHF resonator
assumes B0=B′
20% conversion/pulse
c d
b-c transition
Mike Hayden
Expectations
Initial Experiments: a handful of H; B ~ 1T; measure PSR lines to 1:103 or 30 MHz (difference gives a/h)
Later Experiments: plenty of H; measure PSR lines to 1:106 or ~ 30 kHz (limited by static field homogeneity)
UHF Resonator: measure fcd to 1:106 or 650 Hz (limited by transit broadening)
Combined at B′: gives a/h to 1:106 and p to 2:105 independent of any other measurement
Recommended