Mini-Workshop CTF3 LOST BEAM DAY

Friday, October 24

CERN, building 40, room 40-SS-C01

Motivation

The CLIC drive beam has at the exit of the drive beam generation complex an average beam-power

of about 100 MW. Such a beam can only be operated if local beam losses are kept below a few ppm.

Developing the instrumentation and algorithm needed to achieve this is one of the tasks of CTF3.

In this context the instrumentation has to provide:

- Time and space resolved quantitative measurement of beam loss.

- Quantitative measurement of beam halos and tail distribution

- Time resolved and precise beam current measurement

This has to go together with theoretical and experimental studies to understand:

- Failure modes

- Upper limits for beam losses

- Mechanism of beam tail generation

- Mechanism of beam halo generation

- Interlock and recovery scenarios

Goal of the mini-workshop

Improve the coordination and definition of related activities

Mini workshop program

Presentations	speaker	time	duration
Session A, session chairman Bernd Dehning
Introduction	Jean-Pierre Delahaye	9^00	10
Hamiltonian Tail Generation mechanism	Daniel Schulte	9^10	20+10
Nonhamiltonian Halo Generation mechanism	Frank Zimmermann	9^40	20+10
Coffee break		10^10	30
Session B, session chairwoman Mayda Velasco
Failure modes of the drive beam	Roberto Corsini	10^40	20+10
Overview of BLM uses and developments at CERN	Bernd Dehning	11^10	15+5
Instruments for imaging of beam halo	Anne-Laure Perrot	11^30	20+10
Lunch break		12^00	90
Session C, session chairman Grahame Blair
Calculation of beam loss generated particle fluxes	Matthew Woods	13^30	20+10
Beam loss detection monitors	Thibaut Lefevre	14^00	20+10
Machine protection based on beam current monitors	David Belohrad	14^30	15+5
Beam loss induced thermal deformation of 30 GHz power extraction structure	Samuli Heikkinen	14 ^50	10+5