LHC Collimation Working Group
(former  LHC Beam Cleaning Study Group)


Topics for future meetings

Definition of priorities highest High risk topics (risk of major design changes, risk of failure). Time scale is weeks.
  high Possibility of major changes in design, machine layout or number of components. Time scale is weeks to a couple of months.
  medium Important topic with a medium time scale. Several months. In specific cases the time scale can extend to several years.
  low Important topic with a long time scale of several years. Or a topic of low importance.
     
Energy Deposition Studies Priority  
     
Optimal location of BLM's for collimator tuning in SPS DONE FLUKA team, IHEP
Overall IR7 layout: First results on required absorbers and locations DONE FLUKA team (PDF, PDF, PDF)
Energy deposition in vacuum flanges for various beam loss cases! DONE FLUKA team
AT-VAC (PDF)
Radiation in the RR's of IR7 and required shielding ON-GOING FLUKA team (PDF, PDF, PDF)
Shock heating of water in collimators highest FLUKA team
Radiation effects on the optical fibres for BLM's highest FLIKA team
     
Material for tertiary collimator: W or Cu? DONE FLUKA team ()
Overall IR3 layout: Update on required absorbers and locations DONE IHEP, JBJ (PDF, PDF)
Energy deposition to vacuum pipes in complete insertions. Propose locations for cooled pipes. high FLUKA team, IHEP
Heating of components in case of accident. high FLUKA team (PDF)
Estimate of Ozone for IR7 high FLUKA team
Impact of imperfections on energy deposition high FLUKA team, IHEP
Quench limit versus deposited energy for the superconducting links at IR3 Layout frozen! R. Assmann, R. van Weelderen, JB. Jeanneret, I. Bayshev (PDF)
     
Optimal location of BLM's for the LHC medium FLUKA team, IHEP
Use of high Z material for primary collimator? medium FLUKA team
Showering studies for phase 2 collimation medium FLUKA team
Showering studies at specific locations of beam loss medium-low FLUKA team
Showering studies for tertiary collimators at IR1, IR2, IR5 and IR8 medium-low FLUKA team, IHEP, Mokhov
     
Tuning studies with shower maps (beam loss measurements) low FLUKA team, IHEP
Operational studies (different configurations of collimation) low FLUKA team, IHEP
     
Heating of front and end plate in collimator tank done? FLUKA team
Heat load to springs in the collimator jaws: Equilibrium temperature & radiation resistance. done? FLUKA team
     
Collimator prototype: Precision and control - SPS test    
     
Packages for control DONE M. Jonker, R. Assmann
Components (motor, sensors, cables, ...) DONE S. Redaelli, F. Decorvet
BLM's and DAQ for collimator tuning in the SPS DONE B. Holzer, G. Robert-Demolaize
     
Planning for beam measurements in SPS MD's DONE R. Assmann/G. Arduini (PDF)
Results from collimator tests in the laboratory (measurements with motors/sensors) DONE S. Redaelli (PDF)
Results from collimator tests in the laboratory (mechanical measurements) DONE O. Aberle
     
     
BLM's and DAQ for collimator tuning in the LHC medium B. Holzer
Machine protection constraints for collimator control medium R. Schmidt
Impedance estimates for the SPS DONE Impedance team (PDF1, PDF2, PDF3)
Vacuum test results medium M. Jimenez, A. Rossi
     
Collimator design    
RF contacts and expected impedance DONE S. Calatroni, Impedance team (PDF)
     
Radiation resistance of graphite (experimental tests) high O. Aberle
Erosion damage of copper cooling lines due to high water speed high  
     
Measurement plans for HOM's DONE F. Caspers, T. Kroyer (PDF)
Wire measurement of impedance with uncoated jaws medium F. Caspers
Radiation resistance of NEG coating medium AT/VAC, TS
     
Basic design parameters for different devices DONE R. Assmann (see here)
     
Operational aspects    
     
How many BLM's per collimator? highest  
     
Detection of beam impacts with accelerometers/microphones DONE S. Redaelli, G. Spiezia, A. Masi
Test program for motors high  
BPM systematics with beam loss high B. Holzer (PDF)
Reliability study for collimators in hostile environment high  
Pollution of BLM signal from e.m. noise of other devices (motor, ...) high  
Development of maintenance procedures for servicing/exchanging collimators high  
     
Requirements for alignment in cleaning insertions medium J. Wenninger?
Expected beam loss at the collimators medium M. Lamont
Overall control software for all collimators, including BLM medium  
Study of failure scenarios and estimate of unexpected downtime per year medium  
     
Accelerator physics    
Detailed loss maps high S. Redaelli, G. Robert-Demolaize, R. Assmann
Efficiency and tolerances high G. Robert-Demolaize, S. Redaelli, R. Assmann
     
Tracking tools with detailed aperture models medium G. Robert-Demolaize, S. Redaelli, R. Assmann
Basic simulation of set-up (how many collimators for what intensity - required set-up accuracy - achievable performance) medium G. Robert-Demolaize, S. Redaelli, R. Assmann
Simulation of fine tuning during collision and nominal performance medium G. Robert-Demolaize, S. Redaelli, R. Assmann
Expected performance of tertiary collimators medium  
Use of high Z material for primary collimators medium R. Assmann
Effect of showers induced by lost particles around the LHC ring on the quench performance of superconducting magnets medium  
     
Use scraper below depth of TCP's? low R. Assmann et al
     
Phase 2 collimation    
     
Plans for transition from phase 1 to phase 2 collimation and for installation of phase 2 collimators high R. Assmann, E. Chiaveri
Loss maps for phase 2 high R. Assmann
Brain-storming on innovative phase 2 solutions (goal is to select a few promising paths for prototype studies - including SLAC/US-LARP) medium  
     
Review SPS/TT40 measurements    
     
Aligning the SPS collimator with the BLM   Collimation team/BLM team
Heating of collimator jaws with beam DONE S. Redaelli, G. Robert-Demolaize (PDF)
Mechanical and sound vibrations induce by the beam on the collimator   A. Masi, G. Spiezia, S. Redaelli (PDF)
Review of HOM's measurements at the SPS DONE F. Caspers, T. Kroyer (PDF)
BBQ tune measurements versus collimator position DONE M. Gasior, R. Jones (PDF)
Standard tune measurements with different collimator openening   H. Burkhardt
Comparison between measured and expected impedance ON-GOING E. Metral, F. Zimmermann
Experience with BLM's (SPS + TT40) DONE B. Denhing, B. Holzer, L. Ponce(PDF)
Experience with sensors for position measurements (LVDT's, potentiometers, palmer, ...) - achieved versus expected performance   O. Aberle, F. Decorvet, R. Losito, S. Redaelli
Vacuum of the SPS versus collimator settings   V. Baglin, A. Rossi
Adjusting the collimator angle to the beam profile?   R. Assmann, M. Jonker, S. Redaelli
     

R. Assmann / S. Redaelli, 08/18/2005