1. PACMAN impact on future module design
Hélène MAINAUD DURAND

2. Outline Introduction: presentation of PACMAN project Why PACMAN?
Impact on module through 4 cases:
MB quad + BPM alignment
DB side alignment
MB Accelerating structures alignment
Transport considerations
Outline
Preliminary thoughts
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

3. PACMAN project Web site: http://pacman.web.cern.ch/
PACMAN = a study on Particle Accelerator Components’ Metrology and Alignment to the Nanometre scale
It is an Innovative Doctoral Program, hosted by CERN, providing training to 10 Early Stage Researchers.
Web site:
8 academic partners
8 industrial partners
Duration : 4 years
Start date: 1/09/2013
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

4. Why PACMAN? (1) introduction to CLIC project
At 3 TeV: modules, 2m length
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

5. CLIC project: alignment strategy
Beam off
Mechanical pre-alignment
~ mm over 200 m
Active pre-alignment
µm over 200 m
Beam on
Beam based Alignment & Beam based feedbacks
One to one
steering
Dispersion Free
Steering
Minimization of
AS offsets
Make the beam
pass through
Optimize the position of
BPM & quads by varying
the beam energy
Using wakefield
monitors &
girders actuators
Minimization of the emittance growth
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

6. Why PACMAN? (2) State of the art
Components to be aligned:
Why PACMAN? (2) State of the art ~
Number of components
~ 4000
~ 4000
Budget of error
14 µm
17 µm
17 µm
Quad
BPM AS
Strategy:
Quad
BPM AS AS AS AS
3 steps:
Fiducialisation of the components and their support
Initial alignment of the components on their support
Transfer in tunnel and alignment in tunnel
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

7. Why PACMAN? (3) Example: case of MB quad + BPM
Fiducialisation:
Why PACMAN? (3) Example: case of MB quad + BPM
BPM
Quad
Pre-alignment sensors support
Quad
Stabilization
Nanopositioning
BPM
Pre-alignment sensors support
Initial alignment:
Quad
BPM
Transfer in tunnel & alignment
Stabilization
Nanopositioning
Quad
BPM
Pre-alignment sensors support
Stabilization
Nanopositioning
Pre-alignment sensors support
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016
Tunnel straight reference
of alignment

8. Objectives of PACMAN Some key issues
Magnetic measurements with a vibrating stretched wire (and alternative based on printed circuit boards rotating search coils)
Determination of the electromagnetic center of BPM and RF structure using a stretched wire
Absolute methods of measurements: new measuring head for CMM, combination of FSI and micro-triangulation measurements as an alternative
Improve seismic sensors and study ground motion
Nano-positioning system to check the resolution of BPM
Budget of errors & uncertainties
Combine references & methods of measurements in the same place to gain time and accuracy
Prove their feasibility on a final bench
Extrapolate the tools & methods developed to other projects
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

9. Impact on module: MB quad + BPM
(From F. Morel)
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016
See presentation by Silvia Zorzetti just after

10. Impact on module: MB quad + BPM
More accurate
Less time consuming
Ready to be aligned
Measurements foreseen:
Offset between electrical center of BPM and magnetic axis of Quad
Fiducialisation BPM
Fiducialisation Quad
 electrical zero of BPM + magnetic axis w.r.t external alignment targets within a few microns, at 20°C.
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

11. Impact on module: DB side alignment
Total error budget allocated to the absolute positioning of the components
= radius of the cylinder
= 20 µm for DB quadrupoles ( DB quadrupoles!)
= 100 µm for PETS
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

12. Impact on module: DB side alignment
Objective: adjust the magnetic axis of each DB its nominal position
Sequence:
Wire is put at a nominal position in the CMM coordinate system
Both DB quad are adjusted using the 5DOF adjustment system in such a way that the wire is at their magnetic axis (smallest amplitude of the wire)
The position of the wire is measured w.r.t fiducials and pre-alignment sensor interfaces.
PETS are then aligned in the same coordinate system
More accurate
Less time consuming
Ready to be aligned
Interchangeability between girders
Relax the manufacturing tolerances of girders
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016
See presentation by Jakub Jaros before

13. Impact on module: MB side alignment
See presentation by Natalia Galindo Munoz on Tuesday
Same strategy than before:
Install each AS on a 5 DOF adjustment system
Put the reference its nominal position
Each AS is adjusted in such a way to have the wire at its RF axis.
More accurate
Less time consuming
Ready to be aligned
Interchangeability between girders
Relax the manufacturing tolerances of girders
Relax the manufacturing tolerances of AS (external shape)
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

14. Transport considerations
Development of a high accuracy portable solution (micro-triangulation + FSI), replacing CMM measurements:
Check in-situ fiducialisation + initial alignment of components (with stretched wire or using external alignment targets
Do in-situ fiducialisation + initial alignment in the tunnel, after transport
Transport considerations
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

15. PACMAN project aims at improving the accuracy of fiducialisation & initial alignment of CLIC MB components.
It can be extrapolated to DB components
It will provide a more accurate and faster fiducialisation and assembly of all the components on their girder support
It will relax considerably the tolerances of manufacturing of girders and of some outer references of components.
PACMAN impact on the module design will be discussed in more details in the coming weeks through a cycle of brainstorming meetings, knowing that the solutions proposed are only efficient and accurate at 20 ºC
Summary
Hélène Mainaud Durand
CLIC Workshop 18-22/01/2016

16. Many thanks to:
Claude Sanz, Solomon Kamugasa, Vasileios Vlachakis, Domenico Caiazza, Giordana Severino, Iordan Doytchinov, Peter Novotny, David Tshilumba, Silvia Zorzetti, Natalia Galindo Munoz
Ahmed Cherif, Jean-Christophe Gayde, Jean-Frédéric Fuchs, Stephan Russenschuck, Marco Buzio, Michele Modena, Kurt Artoos, Andrea Gaddi, Manfred Wendt, Nuria Catalan Lasheras, François Morel, Mateusz Sosin, Vivien Rude, Mathieu Duquenne, Antonio Marin, Mickaël Udzig, Michel Rousseau, Bruno Perret, Jakub Jaros, Anna Zemanek, Hermann Schmickler, Steffen Dobert, Carlo Rossi