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 Project ALPHA: Antihydrogen Laser Physics Apparatus OUTLINE ALPHA introduction New Results with Si vertex detector Development for Spectroscopy TRIUMF Review on ALPHA Makoto C. Fujiwara, ACOT, March 13, 2009 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 1
ALPHA Antihydrogen Project • ALPHA: Canadian funding in Jan 2006 First 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 2 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 3 MAKOTO C. FUJIWARA
Trapping Antihydrogen Cold Hbar Production: ATHENA (2002) + Neutral Trap 10 -12 10 -9 AD Na-22 p- Production (Ge. V) e+ Production (Me. V) Deceleration (Me. V) 104 p- 108 e+ Moderation Accumulation (e. V) e. V Trapping (ke. V) Cooling ( ~ me. V) Cooling (~ me. V) Superimpose Magnetic Trap Easy, eh? 4 MAKOTO C. FUJIWARA
Challenges in Anti-Atom Trapping • Antimatter atoms – Can’t buy an antihydrogen gas bottle! – Standard atom trap techniques do not apply – Need to invent new methods • Plasma stability – Normally axial symmetry assures plasma confinement [O’Neil’s confinement theorem] – Magnetic trap field strongly breaks the symmetry 104 p- 108 e+ • Atomic formation processes – Not completely understood e. g. MCF et al, PRL 101, 053401 (2008) “Pushing new physics boundaries in plasma, atomic and other fields” 5 MAKOTO C. FUJIWARA TRIUMF Review Report
Challenges in Anti-Atom Trapping • 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 • Plasma stability – Normally axial symmetry assures plasma confinement [O’Neil’s confinement theorem] – Magnetic trap field strongly breaks the symmetry 104 p- 108 e+ • Atomic formation processes – Not completely understood e. g. MCF et al, PRL 101, 053401 (2008) “Pushing new physics boundaries in plasma, atomic and other fields” 6 MAKOTO C. FUJIWARA TRIUMF Review Report
ALPHA: Before and After 7 MAKOTO C. FUJIWARA
What we have achieved so far • • • • Design, Construction, commissioning: NIM (2006) Trapping of e-, e+, pbars in Penning traps Reported at Electron cooling of pbars TRIUMF Review Hbar production at 3 T (like ATHENA) April 2008 Pbar, e+ confinement in Octupole field: PRL (2007) Hbar production at 1 T: J. Phys. B (2008) New since M Plasma diagnosis in Octupole: Phys. Plasmas (2008) 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 8 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 (30 k ch), DAQ, Monte Carlo, Reconstruction, Analysis and Operation of the Detector 9 MAKOTO C. FUJIWARA
Antihydrogen Detection and Diagnosis n Trapped Hbar detection: n Create Hbars in a neutral trap n Clear all the charged particles n Release the trap in ~20 msec Si: 3 layers 30 k channel n Look for annihilations on the walls n First measurements will be statistics limited n Need best event characterizations, background rejections Position sensitive detection of antihydrogen annihilations n 3 D annihilation imaging: unique tool to study plasmas 10 MAKOTO C. FUJIWARA
Physics with Si tracker 1: Ballistic loss Calculated field lines in neutral trap • “Ballistic” pbar loss in octupole field due to symmetry breaking • Unique annihilation signatures Axial annihilation distribution – Enhanced at trap edges – 4 hot spots at each end • Background for Hbar detection Sarah Seif El Nasr, M. Sc. Thesis (UBC) In prep. for Phys. Lett. B (2009) MAKOTO C. FUJIWARA Cross sectional images at trap edges 11
Result 2: New plasma transport mechanism • Non-harmonicity of electrostatic potentials • Symmetry breaking multipole magnetic fields Zero-rotation bounce resonance Si vertex images Data Simulation Simulated particle orbits Submitted to PRL (2009) Gaining quantitative understanding of new plasma processes 12 MAKOTO C. FUJIWARA
Result 3: Hbar production in anti-atom trap: Submitted to Phys. Rev. Lett. (2009) Hbar yields vs. trap depths Hbar images via Si tracker • Efficient Hbar production in neutral trap, detected via Si • Important milestone for Hbar trapping • Started search for trapped Hbars 13 MAKOTO C. FUJIWARA
Towards Antihydrogen Spectroscopy Walter Hardy (UBC) Mike Hayden, Mohammad Dehghani (SFU) Rob Thompson, Tim Friesen (Calgary) [David Jones, UBC] 14 MAKOTO C. FUJIWARA
m. Wave Spectroscopy: Hardy & Hayden (Anti)hydrogen energy diagram Energy (GHz) 15 1. Positron Spin Resonance trapped states 20 GHz a h – Pulsed m. W at ~20 GHz trapped un-trapped – Look for annihilations – Can start with a few atoms un-trapped states -15 B 0 (T) MAKOTO C. FUJIWARA 15
m. W Spectroscopy: Hardy & Hayden (Anti)hydrogen energy diagram Energy (GHz) 15 655 MHz 1. Positron Spin Resonance – Pulsesd m. W at ~20 GHz trapped un-trapped – Look for annihilations – Can start with a few atoms trapped states 20 GHz a h un-trapped states 2. NMR (pbar spin flip) ALPHA has accepted m. Wave for 1 st spectroscopy attempt -15 B 0 (T) MAKOTO C. FUJIWARA – 655 MHz at magic 0. 65 T turning point: insensitive to 1 st order B inhomogeneity – Double resonance w/ PSR 16
Microwave Tests at CERN & SFU W. Hardy et al, June 2008 at CERN horn focusing reflector Loss > 10 d. B Plasma compatible resonator M. Hayden et al. 2008 SFU prototype f 0: 600 -800 MHz Q: 100 -300 4 cm opposed fingerlike structures 17 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. ” 18 MAKOTO C. FUJIWARA
Extra Slides 19 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 m. W 20 MAKOTO C. FUJIWARA
Project ALPHA Collaboration 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 British Columbia: S. Seif El Nasr, D. J. Jones, W. N. Hardy* University of Calgary: T. Friesen, R. Hydomako, R. I. Thompson* Université de Montréal: J. -P. Martin* Simon Fraser University: M. Dehghani, M. Hayden* TRIUMF: P. Amaudruz*, M. Barnes, M. C. Fujiwara*, D. R. Gill*, ALPHA-Canada L. Kurchaninov*, K. Olchanski*, A. Olin*, J. Storey + Professional Support** York University: H. Malik, S. Menary* * 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 + Undergrad Students: W. Lai, L. Wasilenko, C. Kolbeck MAKOTO C. FUJIWARA 21
ALPHA Publications 1. 2. 3. 4. 5. 6. 7. 8. 9. 'A Magnetic Trap for Antihydrogen Confinement' Nucl. Instr. Meth. Phys. Res. A 566, 746 (2006) 'Antimatter Plasmas in a Multipole Trap for Antihydrogen' Phys. Rev. Lett. 98, 023402 (2007) 'Production of Antihydrogen at Reduced Magnetic Field for Anti-atom Trapping' J. Phys. B: At. Mol. Opt. Phys. 41, 011001 (2008) 'A Novel Antiproton Radial Diagnostic Based on Octupole Indused Ballistic Loss' Phys. Plasmas 15, 032107 (2008) 'Critical Loss Radius in a Penning Trap Subject to Multipole Fields' Phys. Plasmas 15, 032108 (2008) 'Compression of Antiproton Clouds for Antihydrogen Trapping' Phys. Rev. Lett 100, 203401 (2008) Antihydrogen Formation Dynamics in and Anti-atom trap, submitted to Phys. Rev. Lett. (2009) Magnetic multipole induced zero-rotation frequency bounce-resonat loss in a Penning. Malmberg trap used for antihydrogen trapping submitted to Phys. Rev. Lett. (2009) '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) 22 MAKOTO C. FUJIWARA
Canadian Contributions 1. Beam monitors 2. External Scintillator 3. Internal Scintillator 4. MIDAS DAQ System 5. On-line/Off-line Software 6. Si vertex detector design & simulations 7. Si readout electronics 8. Trap control electronics 9. Building Experiment 10. Running Experiment 11. Physics Analysis 12. Developments towards spectroscopy 23 MAKOTO C. FUJIWARA
Building ALPHA at CERN 24 MAKOTO C. FUJIWARA
ALPHA Potential Sensitivity (model dep’t!) Possible CPTV shift (Pospelov) Ge. V Small absolute energy DE probes high energy scale For n=1, m=1 Ge. V, LCPTV = MPl ~ 1019 Ge. V DECPT ~ 10 -19 Ge. V (~10 k. Hz in frequency) 25 MAKOTO C. FUJIWARA
ALPHA Antihydrogen Apparatus Superimpose Penning Trap and Magnetic Trap e+ Octupole magnet Si tracker antiproton trap (3 T) Mixing trap (1 T) Mixing electrostatic potential pbar 26 MAKOTO C. FUJIWARA
ALPHA Challenges Characteristic energy scales: – Plasma energy: space charge (∝ener 2 ) ≈ 10 e. V – Neutral trap depth: (m. DB) ≈ 0. 1 me. V – 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 27 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 104 p- 108 e+ Radial B field Octupole vs Quadrupole • Use Octupole instead of Quadrupole • Perturbation near axis much reduced 28 MAKOTO C. FUJIWARA
Plasma confinement in Octupole trap Phys. Rev. Lett. 98, 023402 (2007) Radial B field : Octupole vs Quadrupole • Use Octupole instead of Quadrupole • Perturbation near axis much reduced • 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 29 MAKOTO C. FUJIWARA
More ALPHA Physics Results • Hbar production in 1 T • New plasma radial diagnosis • Obtained with APD readout Scintillator Arrays operated at 1 to 3 T • Developed at TRIUMF/UBC due to Si detector delays Scot Menary (York) R&D for new beam detector CVD Diamond J. Phys. B 41, 011001 (2008) Fast Track Phys. Plasmas 15, 032107 (2008) 30 MAKOTO C. FUJIWARA
Antiproton Plasma Radial Compression Phys. Rev. Lett. 100, 203401 (May 2008) • Plasma radial control important – Recall E ∝ener 2 • External rotating RF field exerts torque on plasma radial compression • What’s new? Multi-channel plate imaging – Normally need coolant – Use electrons as a coolant 31 MAKOTO C. FUJIWARA
Si Tracker Construction • Summer 2005 Basic design at TRIUMF Compatible with traps • Oct-Nov 2007 6 modules in situ test • June-Nov 2008 38 module out of 60 commissioned (only 20, 000 channel!) • Spring 2009 Si sensors built at Liverpool Full detector (30, 000 ch) will be installed 32 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 33 MAKOTO C. FUJIWARA
AD Future at 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 34 MAKOTO C. FUJIWARA
PSR Lineshapes and spectral resolution no resolution improvement for pulses longer than ~10 ms l tra ec lse sp pu by F d R ite of lim idth w limited by radial homogeneity of field RF pulse length t (s) atoms move significant distances during t Mike Hayden
NMR lineshape and spectral resolution coherent atom-field interactions limited by transit time to ~ 100 ms lim wi ited dth b of y sp RF ec pu tral lse fcd at B 0=B′ B 0 = 1. 01 B′ B 0 = B′ RF pulse length t (s) atoms move significant distances during t Mike Hayden
Power Requirement Estimates for power required to induce spin flip; based on K/Ka-band m. Wave loss measurement and calibration of B 1 in UHF resonator assumes B 0=B′ b- Power (W) ct ra ns c-d itio n tra ns itio n Ej pr ectio few obab n pe ilitie rce s nt/ of a pu lse field homogeneity limit d 20% c conversion/pulse transit-time limit RF pulse length t (s) Mike Hayden
Expectations Initial Experiments: a handful of H; B ~ 1 T; 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 k. Hz (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 gp to 2: 105 independent of any other measurement Mike Hayden
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