High Bandwidth Transverse FeedbackPath to Full Function System

W. Hofle

• Constraints and Assumptions• Staged Path• Decisions and Deliverables

Time Line Constraints

LS1 and LS2• Major works in SPS tunnel only in Long Shutdowns• Long Shutdowns dictated by LHC schedule: assume 3 years LHC running in

between long shutdowns

SPS-LIU • Implementation in LS2 (2018)• Commissioning with beam after LS2 (2019 )• Ramp down of LIU funds with commissioning after LS2

LARP • Ramp up of funds now within LARP required to maintain momentum• Signing of an agreement CERN-US essential for a “Full function system”

developed in collaboration with US labs• Construction Project Funds assumed from 2017

LNF-INFN• Support for kicker design and impedance highly valuable, maintain at level agreed

within Hi-Lumi LHC

Phased Schedule

LHC post LS1 Physics RunYear 1

Phase 1:

20172014201320122011 2015 2016 2018Year 2 Year 3

Demonstrator 1

phase 2 beam tests withBunch trains (ecloud)Scrubbing beamIn ramp and at 450 GeV flat top

Phase 2:

Phase 3: Full implementation

decisionsphase 3:

2019LS1 LS2

Bunch Train Demonstrator R&D and operation

New KickerNew Power amplifiers

Electronics R&D

New Pick-up R&D / prototyping ?

Decisions and Preparations in LS1

LS1 • Locations for new pick-up and kicker: dispersion suppressor LSS3+ and LSS3-• Layout fully compatible with LS2 work for 200 MHz RF system upgrade• Cabling for new pick-up and kicker completed in LS1, 7/8” smooth wall coaxial

cables (lower dispersion than corrugated cables), controls cable• Vacuum chamber layout modifications to be done in LS1 to receive kicker and pick-

up post LS1 1. decisions on interfaces 2. ECR (before end of 2013)• 18 months minimum to produce kicker at CERN (E. Montesinos)

Kicker Design• Design report for kicker: complete before end of October 2013• Decide on

1. bandwidth required2. structure type suitable3. kick strength power market survey and tender for amplifiers

Kicker Construction • construct 1 prototype plus spare parts (Faltin type offers full BW in single structure)• advance with design for strip-line in parallel (more flexibility: BW vs. kick strength)

Deliverables and Milestones: Phase 2

Kicker Design report: October 2013• J. Cesaratto (editor)

Kicker electromagnetic design(s): December 2013• Proposal by Design Team

Kicker prototype(s) mechanical design and production +18 months

• E. Montesinos

Pick-up design / down selection: December 2013

Market Survey & Amplifier Tender out March 2014• RF Group (support by BI, LARP appreciated)

Bunch Train Demonstrator electronics: Mid 2014, tentatively

• SLAC (48 bunch demonstrator)

J. Dusatko, SLAC

J. Dusatko, SLAC

J. Dusatko, SLAC

20142016CERN decision required for futurecrate electronics standard (BE-RF-CS, BE-CO)

Simulations and MD program between LS1 and LS2

Simulations and Control Algorithms:• Deliver results before start-up for Q20 along the ramp (ecloud and TMCI)• Bandwidth and Control algorithms for Q20

MD Program:• 25 ns bunch trains• Scrubbing beam• Single Bunch MDs, lower priority, useful due to higher availability• Beam along the ramp• Increased support by OP and ABP for systematic parameter logging in MDs

Full Function System after LS2

Kickers and amplifiers• 2x4 m can be used in LSS3+ and LSS3- with aperture now considered• Beam tests in phase 2 with new kickers and simulations will determine kick strength

and number of kickers required for the final system• Answers not expected before 2016• Budget for 4 Faltin type kickers with 2x2 kW each or 1 Faltin type kicker and

12x10cm strip-lines (less power required, but if 2 kW amplifier available use it ?)• Production kickers and amplifiers delivered in 2018, cabling in LS2

Pick-up:• Installation at the latest in LS2

Electronics: • Production system deployed in 2019• 2 years for final development and production from start of DOE construction project• Electronics is generic, risk for cost is in power / # kickers required

Summary of Staged Approach

Phase 1 completed: Single Bunch demonstrator with limited power and bandwidth

Phase 2: 1 GHz bandwidth with 3x kick strength of phase 1

Phase 2 MDs: Intra-bunch damping with full bandwidth for bunch train subject to ecloud instability

Phase 3: Decisions on final system

• Construction of final system with DOE funds from 2017 onwards

• Commissioning after LS2 (2019+)