Antimatter Physics Opportunities with ELENA at CERN-AD
ELENA-Canada Working Group
TRIUMF Town Hall MeetingAug 1-3, 2007
This talk is NOT about
• Request for General Infrastructure Support for External Program– Support for external experiments (e.g, G0, Q
weak, ALPHA) an important part of present Five Year Plan
– Should remain so for 2010-15
See Des Ramsay’s report to TUG 5YP Committee
This talk is about:• Proposal for TRIUMF’s Accelerator-Related Con
tributions to ELENA (Extra Low Energy Antiproton Ring)– A new compact cooler ring for ultra-low energy antipro
tons at CERN-AD – Dramatic enhancement of antimatter physics opportu
nities
• No parallel sessions at this meeting --- many people running the experiment at CERN or away
• Have been doing our home work for the past year; submitted “white paper” to TRIUMF/TUEC
Physics Case: Simple and Clear• Comparisons of simplest atom (H) and anti-atom
(Hbar) with highest possible precision
Given that: – Hydrogen: one of best studied system in all physics
(c.f. Nobel Prize 2005)– Cold Antihydrogen: produced in large quantities
(APS, IOP: Top Physics News 2002)
H-Hbar comparison: Obvious thing to do!– Some of best CPT tests, 1st Antimatter Gravity– CERN Review: “no guarantee, but imperative duty”
Technically very challenging. Similarities with ion traps, UCN, but antiparticles difficult
Examples: with1000 trapped Hbars
• 10-12 precision (f~1 kHz) in 1s-2s laser transition (Hänsch 1993)
– e+ mass, charge improved by 4 orders of magnitude– X 10 more stringent CPT test than K0 in absolute ene
rgy scale (within effective field theory)
• With laser cooling – Direct test on gravity on
antimatter
• Precision and feasibility fundamentally limited by number of Hbars
HmghkT
2
1
Vertical height ~1 m for Hbar at 2 mK
Vertical Hbar trap
Why ELENA?
ELENA will provide ultra-low energy phase-space compressed beam enhancing number of usable pbars by up to 4 orders of magnitude
DecelerationStoch., electron
Cooling
PbarAD Degrader foil
3.5 GeV/c
100 MeV/c (5 MeV) 5 keV
Trap
~10-4 efficiency: 99.99% lost
DecelerationE-cooling
ELENA
100 keV 5 keV5 MeV
ELENA Details: Feasibility Study by CERN
Momentum, MeV/c 100 – 13.7
Energy, MeV 5.3 – 0.1
Circumference, m 26.062
Emittances at 100 keV, π mm mrad 5 / 5
Intensity limitation by space charge 1.1 107
Maximal incoherent tune shift 0.10
Bunch length at 100 keV, m / ns 1.3 / 300
Expected cooling time at 100 keV, sec 1
Required vacuum* for Δε=0.5π mm mrad/s,Torr 3*10-12
IBS blow up times for bunched beam* (εx,y=5π mm mrad, Δp/p=1 10-3), s
1.1 / -9.1 / 0.85
* No electron cooling is assumed
ELENA basic parametersELENA Layout
Proposed TRIUMF contributions
• Build upon successful LHC collaboration
• Low energy beam transport lines
• Injection/ejection kickers
• Actual level of contributions depends – Maximum: Capital ~$1-2 M + Manpower– Minimum: Consultation to AD team
Low Energy Beam Lines
• CERN Study: “Beam transport of 100 keV beams will not be an easy task”
• AD team is asking for assistance– CERN is HIGH energy lab; ISOLDE 30 yrs old– Influence of strong stray B fields from trap magnets
• TRIUMF Beam Dynamics Group (Baartman et al): state-of-art beam line expertise with and ISAC, experience for B shield with H- line
• IDEAL MATCH!
Injection/Ejection Kickers
• Mike Barnes– Leading ELENA kicker
design– Similar to AGS kicker
designed by TRIUMF– Expertise with NSERC
funded research– Power semiconductors
Injection kicker
Required angle @5.3 MeV 30 mrad
Magnetic length 505 mm
Integrated magnetic field 0.01 T m•
Max. rise/fall time(1% to 99%)
300 ns
Flat top 400 ns
Good field region, 50mm x 50 mm
Magnet type Transmission-line
Vacuum tube connectors 100-mm Flange (od)
PFN type Cable
System impedance 16.7 Ω
Ejection kicker
Required angle @200 keV 30 mrad
Magnetic length 275 mm
Integrated magnetic field 0.002 T m•
Max. rise/fall time(1% to 99%)
1000 ns
Flat top 400 ns
Good field region 50 mm x 50 mm
Magnet type Lumped inductance
Vacuum tube connectors Flange for ¢ =100mm
PFN type Cable
PFN impedance 25 Ω
ELENA Status
• LOI to CERN by AD Users (2005)• Feasibility Study by CERN AB Div (Draft 30+ pg)• CERN “White Paper”, approved June 2007:
– ELENA in “4th theme” --- “to be partially funded by CERN with external contributions”
– CERN funds earmarked for 4th theme from 2010
• York Atomic Group attempted CFI capital ~2 MCHF for ELENA (2006, unsuccessful)
ELENA-Canada Working Group
• Collaboration of Canadian Antimatter Physics Community related to 3 experiments at CERN-AD (~20 physicists)– ALPHA – ATRAP– ASACUSA
• Large University components, in fields less represented at TRIUMF (AMO, Low Temp, Cond. Matter)
ELENA Canada Working Group
TRIUMF Accelerator DivisionRick Baartman, Mike Barnes (at CERN), Fred Jones
University of British ColumbiaWalter Hardy, David Jones
University of CalgaryRob Thompson
Simon Fraser UniversityMike Hayden
TRIUMF Science DivisionPierre Amaudruz, Makoto Fujiwara, Dave Gill, Leonid Kurchaninov, Konstantin Olchanski,
Art Olin, James Storey
York University Matthew George, Eric Hessels, Scott Menary, Cody Storry, Matthew Weel
Windsor University
Gordon Drake
Summary• Physics case clear and strong• Canadians playing leading roles in the AD experi
ments: ~1/4 of ALPHA and ATRAP• ELENA up to 104 increase in usable pbars• TRIUMF can make focused, yet visible contributi
ons• By doing so, it will strengthen its user base by bri
nging in active university researchers• As national accelerator research center, this is a
n opportunity which should not be missed