R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 1

Task 10.5 -Task 10.5 -High Precision SC High Precision SC Cavity Cavity

Alignment/Diagnostics/BPM Alignment/Diagnostics/BPM with HOM Measurementswith HOM MeasurementsNicoleta Baboi, Ursula van Rienen

Roger M. JonesDESY, Univ. of Rostock, Univ. of Manchester/ Cockcroft Inst.

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 2

Task 10.5 -Overview Participating institutes/staffing

HOM diagnostic measurement method and results achieved to date

Breakdown of each sub-task

Milestones/goals

Finances/budget profile

Summary

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 3

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 4

Sub-task leaders: Nicoleta Baboi (DESY), Ursula van Rienen (Univ. Rostock), Roger M. Jones (CI/Univ. Manchester).

PDRAs: Hans-Walter Glock (Univ. Rostock), Ian Shinton (CI/Univ. of Manchester), TBA (DESY)Ph.Ds: Nawin Juntong (CI/Univ. Manchester), Chris Glasman (CI/Univ. Manchester)

Task 10.5 HOM Diagnostics in SC Accelerator Cavities -Staff

I. Shinton, CI/Univ. of Manchester PDRA

N. Juntong, CI/Univ. of Manchester Ph.d student(PT on FP7)

C. Glasman, CI/Univ. of Manchester Ph.d student(PT on FP7)

H-W Glock, Univ. of Rostock, PDRA U. Van Rienen,

Univ. of Rostock N. Baboi, DESY

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 5

HOM based monitors can radically contribute to the improvement of the beam quality in existing accelerator facilities FLASH at DESY and ERLP at Daresbury Laboratory, as well as the stretched wire test HOM characterisation facility at the Cockcroft Institute, CMTF at DESY, and further facilities using superconducting cavities such as the future XFEL, ILC and 4GLS. The existing international work with SLAC and FNAL, USA, and KEK, Japan is expected to continue as it has important implications on maintaining beam quality in the development of the 16,000 or more main linac accelerating cavities for the ILC.Participating institutes:-         DESY, Germany-         Cockcroft Institute, UK-         Dept. of Physics and Astronomy, University of Manchester, UK-         Institute of General Electrical Engineering, University of Rostock, Germany-        ASTeC, Daresbury Laboratory, UK 

Task 10.5 Task 10.5 HOMs in SC HOMs in SC Accelerator CavitiesAccelerator Cavities

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 6

Task 10.5 Task 10.5 Response of Response of HOM modes to beamHOM modes to beam

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 7

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 8

dump

bunch compressors

collimator section

bypass line

5 accelerating moduleswith 8 cavities each

gunundulators FEL beam

•1.3GHz SC, typically 450-700MeV, 1 nC charge for FLASH/XFEL•HOMs generated in accelerating cavities must be damped.

• These HOMs may also be monitored to obtain beam/cavity info

• Forty cavities exist at FLASH.• Couplers/cables already exist.

• Electronics installed to monitor HOMs (wideband and narrowband response).

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 9

Task 10.5 Analysis of Narrowband Task 10.5 Analysis of Narrowband Signals – Beam PositionSignals – Beam Position

• Resolution of position measurement.– Predict the position at cavity

5 from the measurements at cavities 4 and 6.

– Compare with the measured value.

• X resolution– 9 microns

• Y resolution– 4 microns

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 10

Task 10.5 HOM-BPMs• Calibration based on SVD• Resolution achieved:

– ~5/10m rms (Y/X) single bunch, limited by LO

• Issues:– improve resolution– multi-bunch:

• individual bunches measurable with lower resolution (frep ≤ 1MHz at FLASH)

• speed issues– suitability of various HOMs– alternative electronics– electronics for 3.9GHz cavities

needed

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 11

Task Name Coordinating Institute/Univ.

10.5.1 HOMBPM DESY

10.5.2 HOMCD Cockcroft/Univ. Manchester

10.5.3 HOMDG Univ. Rostock

Task 10.5 Task 10.5 HOM Diagnostics in SC HOM Diagnostics in SC Accelerator CavitiesAccelerator Cavities –Task Breakdown –Task Breakdown

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 12

10.5.1 HOM based Beam Position Monitors (HOMBPM)Initial electronics have been developed for single bunch and installed at FLASH allowing the beam to be centered precisely.Method needs to be verified with additional modes Multi-bunch issues need to be understood.The 3.9 GHz bunch shaping cavities being installed in FLASH and XFEL can readily dilute the beam emittance –important to instrument with electronics modules to diagnose the beam position and improve emittance. Characterisation of HOMBPMs after DESY installation in summer 2009.

10.5.2  HOM Cavity Diagnostics and ALICE/ERLP (HOMCD)HOM spectrum allows one to ascertain the cavity alignment and cell geometry. Will investigate:Mechanical deviations of individual cells from the ideal geometry,Cell-to-cell misalignment,Deformation of fields by couplers.

Task 10.5 Task 10.5 HOM Diagnostics -HOM Diagnostics -Task BreakdownTask Breakdown

I. Shinton, CI/Univ. Manchester PDRA at

FLASH (DESY) HOM shift

C. Glasman, CI/Univ. Manchester Ph.D. student at FLASH (DESY) HOM Shift

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 13

10.5.2  HOM Cavity Diagnostics and ALICE/ERLP (HOMCD) contin.This part of the project requires beam-based measurements at FLASH, DESY and ALICE and RF-based measurements using the wire test facility at CI.

10.5.3 HOM Distributions and Geometrical Dependences (HOMDG)Combining finite element and S-matrix cascading techniques allows the eigenmodes in multiple accelerating cells and cavities to efficiently modeled. The University of Rostock and the University of Manchester have developed a suite of codes.Will apply these powerful computing methods in order to specify allowable tolerances on fabrication and alignment of the TESLA cells and cavitiesIan Shinton’s Beam Time Shifts at FLASH (DESY)

January 2007 (R.M. Jones, CI/Univ. of Manchester Faculty also participated)7/1/07-13/1/07: Participated in HOM shifts September 200725/9/07-29/9/07: Attended as part of HOM shift groups of SLAC, FERMI and KEK – calibration data taken, HOM phase measurements taken across module 4, multibunch data takenJanuary 2008 (Hans-Walter Glock, Univ. Rostock, also participated)15/1/08-23/1/08: 5 shifts in total: remote access control of the machine achieved, 5 collaborative shifts in which calibration data was taken, Multibunch data taken, Phase measurements taken across module 5 for various offsets (beam moved in a circle) – broadband data.September 2008 (C. Glasman, CI/Univ. of Manchester Ph.D. student also participated)21/9/08 – 29/9/08: 1: Collaborative shift, 3 HOM phase/position assigned shifts

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 14

HOM-couplers (pick-ups)

Purpose: on-line measuring device for1. beam alignment on the axes of the 3.9GHz cavities

(& 1.3 GHz cavities) in FLASH (&XFEL&ILC)2. measurement of beam position at the cavity locations

Task: -develop, build, test electronics for 3.9 GHz cavities-interpret signals and integrate in control system-measure cavity alignment

HOM-couplers-one at each cavity end-enable monitoring the HOMs excited by beam

10.5.1 HOMBPM Highlights

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 15

10.5.2 Stretched Wire Measurement of Modes in

Crab Cavity

See: 1. M.Sc. Thesis, N. Chanlek 2007 (Univ. Manchester)

Purpose-built set-up of wire measurement of modes in crab cavity

Dispersion curves of wire displaced from centre of cavity

Measurement of S21 for various offsets Convert to impedance

Dispersion curves reveal expected modal perturbationMeasure S21, convert to impedance, fit to Lorentzian, and hence determine: f, kloss

2 IEEE Trans Nucl. Sc. , vol. 54,No 5, Oct 2007, Burt, Jones and Dexter

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 16

Task 10.5.2 HOMCD –Future Development for ALICE/ERLP

Experience gained on FLASH measurements is invaluable. HOMs in ALICE TESLA cavities will provide information on: 1. Beam position (effectively a built-in BPM)2. Alignment of cells (and groups thereof).

Schematic illustrating ALICE

CI/Univ. of Manchester PDRA I. Shinton (left) and Ph.D. student N. Juntong (right; supported by the Thai Government) will participate in ALICE commissioning in Nov/Dec 2008

Proposal for similar HOM diagnostic measurement on ALICE

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 17

• Resonator without couplers: N ~ 29,000 (2D) N ~ 12·106 (3D)

• Resonator with couplers: N ~ 15·106 (3D) N increases by ~ 500• CSC: „Coupled S-Parameter Calculation“ allows for combination of 2D- and 3D-simulations

HOMcoupler

HOMcoupler

Input coupler

CAD-plot: DESY

K. Rothemund; H.-W. Glock; U. van Rienen. Eigenmode Calculation of Complex RF-Structures using S-Parameters. IEEE Transactions on Magnetics, Vol. 36, (2000): 1501-1503.

Task 10.5.3 –Resonator inc. CouplersTask 10.5.3 –Resonator inc. Couplers

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 18

Identical sectionsHOM1

HOM2

Variation ofcoupler position1,000 frequency points31 lengthsresulting S-matrix: 16 x 16 intern 84 x 84,1h 12min, Pentium III, 1 GHz

SHo

m1H

om2 /d

B

Weak dependence on position

Task 10.5.3 –CSC Resonator ChainTask 10.5.3 –CSC Resonator Chain

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 19

Year Deadline (approx)

Work

1 2009-06-01 Employ post-doc (0.5 FTE)

  2009-07-31 Meeting at DESY

  2009-12-31 Define requirements for HOMBPMs for 3.9GHz cavities

2 2010-06-30 Study HOMs in the 3.9GHz cavities at FLASH

  2010-12-31 Design electronics & LO

  2010-12-31 Meeting (where?)

  2010-06-30 Test electronics

3 2011-03-31 Measurement alignment

  2011-09-30  

  2012-03-31 HOMBPM Calibration

     

4 2012-03-31 Milestone: Prototype HOMBPM-electronics

    Further tests of HOMBPMs and cavity alignment measurements

  2013-03-31 Milestone: Final report

Task 10.5 –PlanningTask 10.5 –Planning

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 20

Deliverables Description/title Nature1 Delivery month2

10.5.1.1Prototype of HOMBPM electronics and code to probe beam centering on 3.9 GHz cavities P 40

10.5.1.2 Report on experimental method and code R 48

Milestones Description/title Nature1 Delivery month2

10.5.1.1 HOM alignment for 3.9 GHz cavity electronics verification

D 40

10.5.2.1

Sub-structure and cavity alignment from HOM signal –algorithm and implementation

R 48

10.5.3.1Final report R 48

Task 10.5 –Milestones/DeliverablesTask 10.5 –Milestones/Deliverables

1=prototype; R=report

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 21

Year FTEs

person-months

Direct costs Indirect costs

Total costs

Requested EC

Personnel

Durable equipm

ent

Consum

able and prototype

Travel

Total direct

Personnel

Material and travel

Total indirect

(€) (€) (€) (€) (€) (€) (€) (€) (€) (€)

 EU post-

doc FDESY

  P D C TD=P+

I T= D+I R < D/3 F D+C+T    1 0.50 0.30 9.60 59520 0 15000 2500 77020 35712 10500 46212 123232 380002 0.50 0.30 9.60 59520 0 15000 2500 77020 35712 10500 46212 123232 380003 0.50 0.30 9.60 59520 0 15000 2500 77020 35712 10500 46212 123232 380004 0.00 0.52 6.20 38465 0 5000 2500 45965 23079 4500 27579 73544 10600Total 2.92 35.00 217000 0 50000 10000 277000 130200 36000 166200 443200 124600

Task 10.5.1 –FinancesTask 10.5.1 –Finances

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 22

Task 10.5.2 –FinancesTask 10.5.2 –Finances

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 23

Task 10.5.3 –FinancesTask 10.5.3 –Finances

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 24

Beneficiary (all costs in

€)

PersonMonths

Total direct costs

Total indirect costs

Total costs(direct+indirect)

ECRequestedfunding¹

UMan/CI 25 199,800 119,880 319,680 95,900

DESY 31 262,500 157,500 420,000 125,800

URostock 24 174,800 104,880 279,680 83,900

…   0 0 0  

…   0 0 0  

…   0 0 0  

…   0 0 0  

…   0 0 0  

Totals: 80 637,100 382,260 1,019,360 305,600

FIXED TARGETS 1,018,500 305,600

Task 10.5 HOM Diagnostics -Finances

R.M. Jones, Task 10.5 HOM Diagnostics, EuCARD WP 10 Kick-off meeting, DESY, 24th March 2009 25

Summary of Task 10.5

HOM characterisation of cavity wake-fields and beam dynamics

for ILC/XFEL. Globalised scattering technique provides a unique

method to enable trapped modes in modules to be probed. HOMs as BPM diagnostic for ILC/XFEL: FP7 proposal as part of

DESY/Cockcroft/Univs Manchester & Rostock collaboration.

Experimental and simulation/analytical aspects at FLASH/DESY. 3.9 GHz bunch-shaping cavities due to be installed at FLASH will

have a significantly larger wakefields (~ a3). Major part of program

will be entail characterising these cavities –beam and cavity

alignment