LHCI – Injector Accelerator for the LHC Motivation. Inject 1.5 TeV proton beams to LHC instead of the current 0.45 TeV beams from the SPS At this new energy the field harmonics [1] of the LHC magnets are satisfactory enough to prevent luminosity losses expected with the - PowerPoint PPT Presentation
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February 1, 2006 AD LARP meeting Henryk Piekarz SC Magnets at Fermilab LHCI – Injector Accelerator for the LHC Motivation Inject 1.5 TeV proton beams to LHC instead of the current 0.45 TeV beams from the SPS At this new energy the field harmonics [1] of the LHC magnets are satisfactory enough to prevent luminosity losses expected with the lower energy of the SPS beams In a long term, the LHCI accelerator would greatly facilitate the implementation of the doubling of the LHC energy (LHC2) The proposed new LHC injection scheme is motivated by desire to advance goals and extend frontiers of high-energy particle physics [1] LHC Design Report Vol 1, O.Brunning et al., CERN-2004-003, Section 4.7 Dynamic aperture
Transcript
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
LHCI – Injector Accelerator for the LHC Motivation
Inject 1.5 TeV proton beams to LHC instead of the current 0.45 TeV beams from the SPS
At this new energy the field harmonics [1] of the LHC magnets are satisfactory enough to prevent luminosity losses expected with the lower energy of the SPS beams
In a long term, the LHCI accelerator would greatly facilitate the implementation of the doubling of the LHC energy (LHC2) The proposed new LHC injection scheme is motivated by desire to advance goals and extend frontiers of high-energy particle physics
Lucio Rossi of CERN proposed (9/05) to consider an Injector Accelerator (LHCI) based on the VLHC low field magnets to boost the initial energy of the proton beam in LHC
HP with help from Gijs de Rijk (CERN) investigated feasibility of the LHCI ring in the LHC tunnel during 3 weeks stay at CERN in 10/05, and produced a report indicating that the LHCI magnet ring can be installed in the LHC tunnel but the beam injection from the LHCI to LHC is a very difficult problem
John Johnstone and Tanaji Sen (11/05) begun investigating the LHCI lattice and the design of the transfer lines
From 11/05 HP is discussing with Vl. Kashikhin options for fast kicker magnets, and with Steve Hays matching power supplies
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Elected Boundaries for LHCI Injector Accelerator Design
- LHCI will fit inside the LHC tunnel without major modifications
- LHCI magnet ring will be installed using regular LHC shutdowns
- The current SPS-LHC injection scheme will remain intact, and it will be used to inject beams to the LHCI
- A reversal to the standard SPS-LHC injection scheme will be possible at any time after implementation of the LHCI
- The LHCI accelerator components will be designed using primarily known technologies, so only the prototyping will be necessary thus allowing to proceed with LHCI design now
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Proposed LHCI – LHC Injection Scheme
The new injection scheme shows only the path from SPS to LHCI to LHC
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
VLHC Low Field Magnet for the LHCI
FNAL
Fermilab cluster:Injection, Extraction,RF, Two Detectors
Typical Stage 1Surface Facility forCryogenics (1 of 6)
Far ClusterLF -> HF Transfer
and Collimation Ring OrientationArbitrary
Stage 1
Required for Stage 2
VLHC: - 233 km accelerator ring - ~ 3200 main arc dipoles - ~ 466 km continued length of transmission line superconductor
LHCI: - ~27 km accelerator ring - 1232 main arc dipoles - ~ 54 km continued length of transmission line superconductor
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Base Magnet of the LHCI Accelerator
• Magnet cross-section area: 26 cm (height) x 24 cm (width)• 1.8 Tesla field (nominal operation)• 0.6 Tesla (beam injection)• 20 mm magnet pole gap• Energized by 100 kA, single turn transmission line superconductor• Coolant – supercritical helium (4.2 K, 4 bar, 60 g/s) • Warm beam pipe vacuum system (ante-chambers required)• Alternating gradient 16 m
We propose that LHCI is basedon the VLHC Low Field magnet
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
LHCI Magnet Location in the LHC Tunnel
It fits easily in the space above the LHC magnet
-Minimum vertical distance between LHC and LHCI beams: 1100 mm
-The holding brackets and the magnets can be installed without disturbing the LHC operations
-The LHe can be tapped at convenient locations from the QRL line (1600 g/s)
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
LHCI Arc Dipole Magnet in LHC Tunnel
Normal tunnel area Area with cryogenic feed tower
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
VLHC Low Field Magnet Tests
• Test gradient dipole magnet - 1.5 m long• Transmission line superconductor – 16 m long• Current leads: 100 kA (RT->LHe)• Power supply: 100 kA dc• Quench detection & protection system: standard• Magnetic measurements: - Tangential coil: 0.7 m long, 15 mm diameter - 102 element Hall Array• Supporting cryogenics - Two – phase LHe at ~ 5 K - Three independent flows of 6 g/s each
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
100 kA dc Power Supply
Steven Hays: MOA04P001
1.5 V @ 100 kA Switcher PowerSupply was used as both: - Ramping supply, and - Holding supply
It consists of: - Bulk 400 V, 240 kW filtered and regulated supply - 10 switcher cells connected in parallel at the input to the magnet current leads
Operated as constant power device:No regulation was available for using the load current, or magnetic field
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
100 kA dc Current Leads
Yuenian Huang: WEA03PO04Lead: 202 Cu rods, 1650 mm long, 6.35 mm dia.Est. heat transfer: 200 W/m2_KTemperature profiles: Blue dots – no current Purple square: 90 kA, stable Red triangles: 100 kA, 5.6 g/s, stable for 15’
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Magnet and B-field Measuring Instrumentation
Magnet view (tangential coil side) Magnet view (Hall station side)
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Magnetic Measurements
Gueorgui Velev, TUA07PO02
Probe: 15.2 mm dia. x 754.1 mm longVespel (polyimide) used to form the probe (winding support) and bearings.
Field Harmonics measured to:order 10 at 1.966 Tesla (collisions),and order 6 at 0.1 Tesla (injection)
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Magnetic Measurements
Quadrupole component is as designed; ~ -415 units, both atinjection and full field 1.966 T.
102 element Hall Probe confirmsthe +/- 4% gradient.
Sextupole component very small;~ few units, and no change frominjection to the full field 1.966 T.
The b4 – b10, and the a4 – a10 also << 4 units, or << 0.04%.
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
VLHC Low Field Magnet Team
Members of the VLHC Low Field Magnet Group:Ruben Carcagno, Brad Claypool, George W. Foster, Steven Hays, Yuenian Huang, Vladimir Kashikhin,Ernest Malamud, Peter Mazur, Roger Nehring, Andrew Oleck, Henryk Piekarz, Roger Rabehl, Phil Schlabach, Cosmore Sylvester, George Velev, James Volk (FNAL) and Masayoshi Wake (KEK)
Five papers published at MT-19, Genoa, Italy, 2005
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Principle of the LHCI-LHC Beam Transfer
After the LHCI ring filling is complete, the kicker magnets are turned off as soon as the last proton bunch passed through them.
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
LHCI-LHC Transfer Line Boundaries
- LHC-LHCI vertical separation: 1100 mm- LHC beams separation: 194 mm ( LHCI: 150 mm)- Total length of ½ of straight section: 260 m- Total available free space between D1 and Q7: 176.5 m
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
LHCI Beam Pipe Inside the LHC Magnets
LHCI beam pipes can be inside the LHC magnet cryostat. Thisallows to minimize to 170 mmthe required LHCI beam deflection in the Kickers
The fringe B-field outside the yoke is very small , and so is the heat load of the LHCI pipe Modification of LHC magnets can be done using the spares, and then swapping them with those in the tunnel
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Fast Kicker Magnets
A conceptual view of the fast kicker magnet arrangements:(A)- LHCI and LHC beam share the beam pipe(B)- LHCI and LHC beams are separated
A B
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Fast Kicker Magnet Power Supply
Magnet gap: 6 cm => 4 T, 90 kA, 30 KV @ 3 usec & 1 uHenry
February 1, 2006 AD LARP meeting Henryk Piekarz
SC Magnetsat Fermilab
Schedule & Cost
Construction 5 – 6 years, and $150 M of total cost
