LHC Collimation Working 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