PACMAN impact on future module design Hélène MAINAUD DURAND

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

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: http://pacman.web.cern.ch/ 8 academic partners 8 industrial partners Duration : 4 years Start date: 1/09/2013 Hélène Mainaud Durand CLIC Workshop 18-22/01/2016

Why PACMAN? (1) introduction to CLIC project At 3 TeV: 20 000 modules, 2m length Hélène Mainaud Durand CLIC Workshop 18-22/01/2016

CLIC project: alignment strategy Beam off Mechanical pre-alignment ~0.2 - 0.3 mm over 200 m Active pre-alignment 14 - 17 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

Why PACMAN? (2) State of the art Components to be aligned: Why PACMAN? (2) State of the art ~ 140 000 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

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

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

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

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

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 (40 000 DB quadrupoles!) = 100 µm for PETS Hélène Mainaud Durand CLIC Workshop 18-22/01/2016

Impact on module: DB side alignment Objective: adjust the magnetic axis of each DB quad @ 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

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 wire @ 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

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

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

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