f lhc accelerator research program accelerator systems tanaji sen fnal/apc project management ...
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LHC Accelerator Research ProgramAccelerator Systems
Tanaji SenFNAL/APC
Project management Accelerator Physics Instrumentation Beam commissioning LHC@FNAL Software (LAFS)
September 26, 2007
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T. Sen: LARP Accelerator Systems
Accelerator Systems
• The Accelerator Systems effort is a collaboration between: BNL, FNAL, LBNL, SLAC
• FNAL effort in - Accelerator Physics: IR upgrade, Wire
compensation, Electron lens compensation
- Instrumentation: Schottky monitor, Tune and chromaticity tracker, AC dipole
- Collimation: Tertiary collimators - IR, Hardware and Beam commissioning
September 26, 2007
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T. Sen: LARP Accelerator Systems
FY07 Accelerator Systems Budget
September 26, 2007
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T. Sen: LARP Accelerator Systems
APC and Accelerator Division
• FY07 Budget ~ $ 0.84 M• Current Effort: 19 people - Scientists: 10 - Engineers and designers: 5 - Guest scientists and post-docs: 2 - Graduate student: 1 - Hardware commissioner at CERN: 1
September 26, 2007
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T. Sen: LARP Accelerator Systems
IR Upgrade Studies
Issues with quads-1st vs dipoles-1st
• Apertures and peak fields• Chromaticity• Beam-beam interactions• Geometric aberrations• Energy deposition• Luminosity gain at lower L*
Beam-beam compensation is required to benefit from lower L*
Slim magnets inside detectors under study
Local chromaticity compensation scheme developed
Luminosity vs L* Geometric Aberrations vs L*
Beam-beam footprints Energy deposition and L*
J. Johnstone, N. Mokhov, I. Rakhno. T. Sen
September 26, 2007
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T. Sen: LARP Accelerator Systems
Beam-beam wire compensation
• Au experiments in RHIC, 2007
Simulations, FNAL
Tune shift vs separation Tune scan of dynamic aperture
BTF comparison Loss rates
FNAL: H.J. Kim. T. Sen; BNL, LBNL and SLAC
September 26, 2007
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T. Sen: LARP Accelerator Systems
Tertiary Collimators
• Detailed MARS15 calculations confirmed, tertiary collimators do their job both in IP1 and IP5.
• Energy deposition and radiation levels are well under control.
• Betatron cleaning contribution dominates over beam-gas, with energy deposition in IRQ well below limits.
• Particle fluxes at CMS detector calculated for both sources, with beam-gas being a driver at large radii.
Tungsten tertiary collimators designed to protect the LHC high-luminosity inner triplets IP1 and IP5 and the ATLAS and CMS detectors against:
• Any remnants of a mis-steered beam not captured in the IP6 beam abort system.
• Tertiary halo generated in the IP3 and IP7 collimation systems.
• Products of beam-gas interactions in a 550-m region upstream of IP1 and IP5.
N. Mokhov, I. Rakhno
Muon flux: plan view
September 26, 2007
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T. Sen: LARP Accelerator Systems
Schottky Monitor
Schottky Monitor will provide unique capabilities– Only tune
measurement during the store
– Bunch-by-bunch measurement of parameters such as Tune, Chromaticity
• Non invasive Technique
• Diagnosis of beam-beam effects and electron cloud
• Monitors installed in LHC in summer 2007
FNAL. R. Pasquinelli, A. Jansson, …; CERN: F. Caspers, …
September 26, 2007
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T. Sen: LARP Accelerator Systems
Schottky Monitor
September 26, 2007
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T. Sen: LARP Accelerator Systems
Tune and Chromaticity tracker
• Tune tracker is operational in the Tevatron, RHIC and SPS
• Tevatron: 2 novel methods of chromaticity tracking: (i) continuous head-tail (ii) rf phase modulation method
• Head-tail method investigation to continue at SPS, RHIC
• Phase modulation method will be developed further in the Tevatron
Head-tail method
Phase modulation
FNAL: C.Y. Tan; BNL: P. Cameron, CERN: M. Gasior, R. Jones
September 26, 2007
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T. Sen: LARP Accelerator Systems
AC dipole studies
Machine Tevatron LHC
E [GeV] 980 7000
σ [mm] 0.5 0.3
Bl [Gm] (4σ)
140 165
fac dipole
[kHz]20.5 3, 8, 14,
19,…
Collaborators UT Austin: R. Miyamoto , S. Kopp FNAL: A. Jansson, M. Syphers BNL: M. Bai, R. Calaga, W. Fischer, P. Oddo CERN: H. Schmickler, J. Serrano
An AC dipole produces oscillating dipole magnetic fields A sustained oscillation can be excited without blowing up the beam size The LHC AC dipole strength is close to that of that the Tevatron AC dipole
βV @ B0 [cm]
βV @ D0 [cm]
Prot Helix
27.9 30.8
Pbar Helix
35.9 36.2
September 26, 2007
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T. Sen: LARP Accelerator Systems
Electron lens compensation
TEL onon:
dQ=0.001
Effects ~comparableexcept TELcan affect individual bunches
Tevatron: TEL2 installedLHC: Simulation
TEL2 acts on proton bunches and increases both Intensity and Luminosity lifetime. Effect is reproducible Compensation works for ~10hrs into a store Head-on compensation under study for RHIC and LHC
V. Shiltsev et al
September 26, 2007
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T. Sen: LARP Accelerator Systems
Hardware Commissioning
• IR commissioning has much overlap with general Hardware Commissioning– Fermilab commissioners are split between these two
tasks– cryogenics, power, magnet experts sent– personnel “integrated” into CERN departments, teams
M. Lamm
September 26, 2007
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T. Sen: LARP Accelerator Systems
Beam commissioning
LHC@FNAL provides conduit to the CERN CCC and accelerator data, as well as CMS system
• LHC@FNAL, will allow monitoring and help diagnose from Fermilab during commissioning• Used to collaborate on SPS machine studies• Major challenge has been to make secure connections to CERN control system, without compromise of control/operation from CERN
E. Harms, M. Syphers
September 26, 2007
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T. Sen: LARP Accelerator Systems
Long term visitors
Beam commissioning:– CERN: must meet specific needs; no “tourists”– wish to send ...
• a) “Sr” personnel, with expertise• b) “Jr” personnel, who can lead in future (e.g.
Toohig fellows) LTV Advisory Committee formed (chaired by M. Syphers)
– members from all labs and from CERN– meet regularly to determine program priorities and
recommend long-term visitors to be sponsored by LARP
– funded to send several FTE’s each year
LARP will send several beam commissioners; ~10 long term visitors approved by LARP and CERN
September 26, 2007
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T. Sen: LARP Accelerator Systems
LAFS
• Software effort funded by Fermilab, outside of LARP. ~5-6 FTEs• Coordinated with CERN control group and input from operations
group• Role-based Access
– authentication of LHC applications user– authorization from CERN for the user– has become fundamental to the LHC software application development– settings history for all LHC applications will be generated through RBA
• Sequencer– initiating software tasks “on event” in sequential order
• ex: fill ring 1; measure emittances, etc.; fill ring 2; ...– strong intellectual input based on Tevatron experience
• Instrumentation Applications– tune display control room application
• most mature coding at this point– wire scanner control room application
• working on requirements and design documents– synchrotron light control room application
• working on requirements and design documents
CERN liaison: 1 person at CERN for a year coordinating efforts
D. McGinnis et al
September 26, 2007
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T. Sen: LARP Accelerator Systems
Summary
• Accelerator Systems FY07 budget = $3.8M among BNL, FNAL, LBNL and SLAC. Nearly the same to 2009
• APC and Accelerator Division efforts in - IR upgrade: several layouts considered for Phase II - wire compensation: simulations compared with
experiments at RHIC - elens compensation: improved luminosity lifetimes in
Tevatron - tertiary collimators: simulations show they are effective - Schottky monitors: installed in the LHC tunnel - tune/chromaticity tracker: operational/continuing
studies - AC dipole: used for optics measurements - Hardware commissioning: continuing presence at CERN - Beam commissioning: approved list of long term visitors - LHC@FNAL for accelerator scientists and CMS - LAFS providing control room software, applications
September 26, 2007
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T. Sen: LARP Accelerator Systems
Backups
September 26, 2007
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T. Sen: LARP Accelerator Systems
New LARP AS tasks in FY08
• Joint IR studies • Crystal collimation
• Electron-lens compensation
• Crab cavities
September 26, 2007
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T. Sen: LARP Accelerator Systems
LAFS FY07 Org Chart
September 26, 2007
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T. Sen: LARP Accelerator Systems
Budget scope