Status of energy deposition studies IR7

1
Status of energy deposition studies IR7

• A. Ferrari, M. Magistris, M. Santana, M. Silari,
  V. Vlachoudis

Review of the LHC Collimation Project 30 June 2
July 2004
2
Overview

• Introduction to beam collimation
• Main issues to be studied
• New features of FLUKA
• Implementation of the geometry
• Future work
• This talk is a status report of a work in
  progress. No results are available at the moment.
  
• The FLUKA input is ready and debugged,
  simulations are starting the first week of July.

3
Two warm LHC insertions dedicated to cleaning
IR3, IR7

• Collimation systems
• Momentum and betatron cleaning
• Two beams

4
Principle of beam collimation
Cleaning with collimators (warm)
IR7
RR
RR
Dispersion suppressor (SC)
p,e,p
p,e,p
p,e,p
Beam 1
Primary collimators Damage?
Secondary collimators Damage?
SC magnets Quench?
5
Issues to be studied

• Energy deposition in collimators and downstream
• Damage to equipment in cleaning insertions
• Energy deposition in SC magnets in DS section
• Damage/perturbation to electronic equipment and
  cables
• Position of absorbers to cure problems
• These issues can be studied by means of the MC
  cascade code FLUKA.

6
FLUKA physics

• Physical models available for cross-checking
• FLUKA standard model
• DPMJET 2.5
• DPMJET 3
• Possibility of simulating ions
• Single scattering for incident particles at
  grazing angle

7
FLUKA geometry

• New features of the latest version
• repetition of objects according to symmetry
  transformation (rotation, translation,
  reflection, or combination of these).
• assignment of names to bodies and regions.
• These features allow implementing a complex
  geometry with a modular approach.

8
Advantages of the modular approach

• Time optimisation
• IR7 (more than 200 major components) can be
  implemented with less than 20 prototypes.
• Maintenance
• Any improvement in the prototype geometry applies
  to all replica in the tunnel.
• A new component can be added without modification
  of the existing geometry.
• Avoid duplicating efforts
• Every module can be used or modified by different
  users for future studies.

9
Prototypes
Collimators, dipoles, quadrupoles, sextupoles,
multipoles
MB
MQT
10
Reflection MQW Vertical and Horizontal
11
Rotation and run-time corrections Primary and
secondary collimators

• Rotation around the beam direction and the
  vertical axis
• Jaw material (carbon, metal)
• Collimation gap and misalignment (run-time)

12
Additional components

• Beam Loss Monitors (air volume).
• Vacuum pipes (need for definition of bake-out
  equipment close to pipe ? AT/VAC).
• Tunnel walls and estimates for cables.
• Electronic equipment in RRs (K. Tsoulou).

13
A flexible geometry

• The magnetic fields and the beam loss
  distribution are described in user written
  routines.
• A specifically written program creates
  automatically the full geometry from an on-line
  file.
• Any change in component position, collimator
  rotation or jaw misalignment is automatically
  implemented.
• With minimal modifications, the same program can
  be used to implement different sections of LHC.

14
Special techniques and physics options

• Biasing techniques (Russian roulette,
  splitting, leading particle biasing and region
  importance)
• Energy threshold
• Electromagnetic cascade
• Particles to be tracked
• These options must be defined by the user
  according to the specific case studied.

15
IR7, Straight section
16
Summary

• Large initial effort to set up flexible and
  complete model of IR7 and cold dispersion
  suppressor.
• The straight section of IR7 is fully implemented.
• Prototypes and magnetic field of all components
  in DS have been implemented ? adjusting
  positions.
• Full simulations starting first week of July.
• First complete picture end of July.

17
(No Transcript)