Presentation on theme: "FLAIR 2 February 2009T. Eriksson CERN BE/OP1 The CERN Antiproton Decelerator (AD) Status and Future."— Presentation transcript:
FLAIR 2 February 2009T. Eriksson CERN BE/OP1 The CERN Antiproton Decelerator (AD) Status and Future
FLAIR 2 February 2009T. Eriksson CERN BE/OP2 Introduction Based on a previous CERN machine (the Antiproton Collector – AC), AD started producing low-energy antiproton beams for physics in Here we will discuss problems linked to AD:s co-existance with CERN main programs and recent decisions taken with regard to AD:s future.
FLAIR 2 February 2009T. Eriksson CERN BE/OP3 Background AA –3.57 GeV/c Antiproton Accumulator ring; –10 12 pbars stored (peak). p/pbar collisions in SPS AAC (AA+AC) –Large acceptance Antiproton Collector ring added. Production rate increased 10-fold to 6*10 10 pbars/h –+ low energy experiments in LEAR ?AD –AC converted from fixed energy storage ring to Decelerator. 5*10 7 pbars slowed down to 100 MeV/c (5.3MeV kinetic). Local experimental area. –Fast extraction for Penning traps + other low energy exp.: ATRAP: Production and study of trapped Hbars ALPHA: Production and study of trapped Hbars ASACUSA: Spectroscopy on Antiprotonic helium, traps etc. etc. ACE: Biological effect of Pbars => tumor treatment
FLAIR 2 February 2009T. Eriksson CERN BE/OP4
FLAIR 2 February 2009T. Eriksson CERN BE/OP5 AD Basic Parameters –Circumference182 m –Production beam1.5*10 13 protons/cycle –Injectedbeam5*10 7 pbars/cycle –Beam momenta max-min3.57 – 0.1 GeV/c –Momenta for beam cooling Stochastic3.57 and 2.0GeV/c Electron0.3 and 0.1GeV/c –Transverse emittancesh/v200 – 1 mm.mrad –Momentum spread6*10 -2 – 1*10 -4 dp/p –Vacuum pressure, average4* Torr –Cycle length100 s –Deceleration efficiency85 %
FLAIR 2 February 2009T. Eriksson CERN BE/OP6 Operation statistics Run time (h) Total Physics Md Beam available for physics (%) Uptime AD machine (%)
FLAIR 2 February 2009T. Eriksson CERN BE/OP run Key dates: 23/4: Ring closure, start HW-tests 11/5: Start setting up with beam 8/6: start physics
FLAIR 2 February 2009T. Eriksson CERN BE/OP8 AD Consolidation Many HW breakdowns of major components since 2004: several ring/transferline magnets, vacuum leaks, power supplies etc. Lengthy repairs due to lack of spares, need for vacuum bakeout, obsolete equipment, loss of know-how etc. Reduced AD maintenance/support due to other CERN priorities => Limited consolidation budget for urgent measures granted following approval of AD running Consolidation budget requested in 2008 for continued AD operation in the medium/long term Focus is mainly on consolidating existing equipment The two scenarios under consideration are: –(1) Continued operation until the end of 2012 with no major modifications to the AD machine –(2) Operation until the end of 2016 with the possibility to implement the proposed ELENA upgrade.
FLAIR 2 February 2009T. Eriksson CERN BE/OP9 AD Consolidation Analysis of breakdown risks, identification of items and costs for consolidation was done as well as a risk score classification. Some 40 items have been identified, costs (manpower+material) estimated and summed up for the 2 scenarios 2012/2016. The matter was discussed at the Research Board meeting 5/12/09; It was decided to execute approx. 1/3 of the proposed 2016 consolidation program. Quote: “Since AD operation will be incompatible with the new PS2, this sets a clear end-point to the programme in It was agreed that the strategy to be followed should have the aim of maintaining the AD facility operational until then, but consistent with the budgetary constraints.”
FLAIR 2 February 2009T. Eriksson CERN BE/OP10 Proposed new experiment: AEGIS The proposed AEGIS experiment was in principle approved as AD-6 at the RB meeting 5/12/09. Budgetary details remain to be worked out. Standard fast extraction of the 100 MeV/c beam The extension of the existing ACE beamline has been foreseen since the beginning of AD and requires manufacturing and installation of 2 quadrupoles, 1 dipole, 3 combined H/V corrector magnets and 3 bpm:s as well as vacuum chambers and equipment. Work is planned to be started in 2009, first beam in 2011
FLAIR 2 February 2009T. Eriksson CERN BE/OP11 Long-term AD future AD and antiprotons. According to the planning of the FAIR project, the antiproton facility in GSI should have succeeded to the AD after the year The continuation of antiproton experiments at CERN after the PS complex is decommissioned is therefore unlikely. In spite of this, if an antiproton facility is still needed on the CERN site, the following scenarios can be envisaged: –For a limited period of time (1-2 years) the old PS complex could be kept active and dedicated to the production of antiprotons. –For continuation in the medium term, the AD target could receive a proton beam from PS2 via a 1.3 km transfer line, using a new 650 m long tunnel and passing through 3/4 of the PS ring. –For continuation in the long term, a new and modern antiproton facility with its target area should be built in a cavern close to PS2.
FLAIR 2 February 2009T. Eriksson CERN BE/OP12 Connection to AD for continued Pbar physics in the medium term.
FLAIR 2 February 2009T. Eriksson CERN BE/OP13 In the long term, a new antiproton facility could be built either 40m underground or in a surface building further away from PS2 Possible PS2 surface experimental area Possible PS2 underground experimental areas
FLAIR 2 February 2009T. Eriksson CERN BE/OP14 Sideview of baseline scheme
FLAIR 2 February 2009T. Eriksson CERN BE/OP15 Long-term AD future May 09 meeting to discuss Non-LHC physics Objective is to define strategies for optimizing physics output at CERN… and world-wide We might know more about the future of low- energy pbar physics after that…..
FLAIR 2 February 2009T. Eriksson CERN BE/OP16 AD – future improvements: ELENA
FLAIR 2 February 2009T. Eriksson CERN BE/OP17 ELENA basic parameters Energy, MeV 5.3 – 0.1 Circumference, m 25.6 Emittances at 100 keV, π mm mrad 5 / 5 Intensity limitation by space charge 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 IBS blow up times for bunched beam* (ε x,y =5π mm mrad, Δp/p= ), s 1.1 / -9.1 / 0.85 * No electron cooling is assumed
FLAIR 2 February 2009T. Eriksson CERN BE/OP18 AD – future improvements: ELENA 3,5 years project duration 10 MCHF + 50 Man-years needed CERN approval conditioned to external funding 50/50 ELENA was not discussed during RB 5/12/09 External partners interested in participating in the project
FLAIR 2 February 2009T. Eriksson CERN BE/OP19 TSR => ELENA ? A visit to the TSR facility at MPI-K Heidelberg has enabled us to verify the feasibility of using an appreciable amount of the TSR machine components for the construction of the proposed low energy antiproton ring, ELENA. Even thought the TSR ring size (53 m) does not fit the dimensions of the ELENA ring, which would have a circumference of about 30 m, most of the TSR elements could be used for the smaller ring. Magnets: All 8 bending magnets fit the requirements. 20 quadrupole magnets are available, 8 are required for use in ELENA and the rest will be used in the transfer line or kept as spares. Orbit correction:The 8 backleg windings on the main bends will be used for the horizontal orbit correction. A total of 12 dipoles are available to correct the vertical orbit or to provide extra elements for the horizontal correction. Injection & ejection:The magnetic and electrostatic septa of TSR could be adapted for use in ELENA. The kickers, however, do not fit the requirements. In addition an number of magnetic correctors can be used in the AD-ELENA transfer line. Electron cooling:It is proposed to use the electron target experiment as an electron cooler for ELENA. This device comes complete with the Faraday cage and high voltage platform. A modification to the electron gun will be needed in order to exchange the photocathode with a conventional thermionic cathode.
FLAIR 2 February 2009T. Eriksson CERN BE/OP20 TSR => ELENA ? Vacuum:All vacuum chambers are made of 316LN stainless steel and are bakeable. Turbo molecular pumps, ion pumps and Ti sublimation pumps can all be re-used in ELENA. In addition 5 sector valves are also available as well as vacuum gauges and residual gas analysers. Only the pumps and the valves are equipped with bakeout jackets. The rest of the machine is equipped with heating strips and insulating material. The complete control of the bakeout could also be used. Instrumentation:8 horizontal/vertical pick-ups (LEAR type, fully bakeable) can be used to measure the closed orbit. The intensity is measured with a standard Bergoz BCT and the circulating beam profile is measured with ionization profile monitors and a scraper. Schottky pick-ups are installed but their use in ELENA might be limited due to the low number of particles. They would be useful for the tune measurement where a dedicated BTF kicker is available. Taking the above into consideration, we estimate that between 2.5 to 3 MCHF could be saved by using TSR elements in the construction of the ELENA post- decelerator ring. This represents about 25% of the total budget.
FLAIR 2 February 2009T. Eriksson CERN BE/OP21 TSR => ELENA ? Proposed ELENA/TSR lattice
FLAIR 2 February 2009T. Eriksson CERN BE/OP22 THANK YOU