WP4-CHOPPERWP4-CHOPPERcoordinated by A. Lombardicoordinated by A. Lombardi

HIPPI yearly meeting, sep28-sep30 2005HIPPI yearly meeting, sep28-sep30 2005

COSENERS HOUSE- Abington COSENERS HOUSE- Abington Hosted by CCLRCHosted by CCLRC

General infoGeneral info

Contributors :Contributors : RAL : C. Prior, M. Clarke-Gayther, G. Bellodi, C. PlostinarRAL : C. Prior, M. Clarke-Gayther, G. Bellodi, C. Plostinar CERN : M. Paoluzzi , F. Caspers, M. Morvillo, L. Bruno, K. CERN : M. Paoluzzi , F. Caspers, M. Morvillo, L. Bruno, K.

Hanke, E. Sargsyan, J.B. Lallement, M. Hori, A. LombardiHanke, E. Sargsyan, J.B. Lallement, M. Hori, A. Lombardi

WEB site : WEB site : http://lombarda.home.cern.ch/lombarda/WP4/WP4main.htmhttp://lombarda.home.cern.ch/lombarda/WP4/WP4main.htm

Yearly meeting : Yearly meeting : 13-15 april 2005 13-15 april 2005 joint with WP5joint with WP5

PublicationsPublicationsCARE Conf-05-015-CARE Conf-05-015-HIPPI (PAC05)HIPPI (PAC05)

Michael A. Clarke-Michael A. Clarke-GaytherGayther

““Fast-Slow” Beam Fast-Slow” Beam Chopping for Next Chopping for Next Generation High Generation High Power Proton Power Proton DriversDrivers

CARE/HIPPICARE/HIPPIDocument-05-003Document-05-003

M. PaoluzziM. Paoluzzi Status of cern Status of cern chopper driver and chopper driver and the solid state the solid state alternativealternative

CARE/HIPPI CARE/HIPPI Document-05-008Document-05-008

M. A. Clarke-M. A. Clarke-GaytherGayther

HIPPI Work Package HIPPI Work Package 4 (WP4): The 4 (WP4): The RAL†Fast Beam RAL†Fast Beam Chopper Chopper Development Development ProgrammeProgramme

Progress Report for Progress Report for the period: January the period: January 2004 – June 20052004 – June 2005

Task (original)Task (original) compare two different approaches to building compare two different approaches to building

and integrating in a matching line a device able and integrating in a matching line a device able to remove micro-bunches with a time duration of to remove micro-bunches with a time duration of few nsecfew nsec

both approaches make use of electrostatic field both approaches make use of electrostatic field across two parallel plates placed longitudinally in across two parallel plates placed longitudinally in the beam line and driven by a fast amplifierthe beam line and driven by a fast amplifier

the difference between the two approaches is in the the difference between the two approaches is in the amplifier designamplifier design, in the range of duty cycle that it can cover , in the range of duty cycle that it can cover and in the and in the integration of the chopper in the beam lineintegration of the chopper in the beam line. .

TasksTasksID Task Name Milestones Deliverables

44 3.2.6 RF design of 352 MHz multi-gap resonator May-05 Design report45 3.2.7 Engineering of resonator, coupler and tuner46 3.2.8 Final design of 352 MHz multi-gap prototype47 3.3 CH RESONATOR48 3.3.1 Design of tuning system Jun-05 Intermediate report49 3.3.2 Construction of CH tuning system50 WP4: CHOPPING51 4.1 CHOPPER STRUCTURE A52 4.1.1 Pre-prototype construction Jun-05 Design report53 4.1.2 Pre-Prototype testing Mar-05 Intermediate report54 4.1.3 Driver construction, testing55 4.1.4 Full scale prototype design56 4.1.5 Full scale prototype construction Aug-06: Prototype ready57 4.1.6 Pre-prototype testing w/o beam58 4.2 CHOPPER LINE59 4.2.1 Dump design60 4.2.2 Dump construction Jun-05 Intermediate report61 4.2.3 Beam line assembling62 4.3 CHOPPER STRUCTURE B63 4.3.1 Pre-prototype design and test Jun-05 Intermediate report64 4.3.2 Prototype design Jun-06 Design report65 4.3.3 Prototype construction66 WP5: BEAM DYNAMICS

FZJFZJ,IN2P3-Orsay

FZJ,IN2P3-Orsay

IAP-FUIAP-FU

CERNCERN

CERNCERN

CERN

CERNCERN,CEA,LPSC

CERN,CEA,LPSC

RALRAL

RAL

12 01 02 03 04 05 06 07 08 09 10 11 12 01 02 03 04 05 06 07 08 09 10 11 12 01 02 03 04 05 06 07 082003 2004 2005 2006

WBS # Title Original begin date (Annex 1)

Original end date (annex1)

Estimated Status Revised end date

4.1 Chopper structure A (CERN)

4.1.1 Pre-prototype construction January 2004 June 2004 Finished June2005

4.1.2 Pre-prototype testing July 2004 November 2004 Combined with task 4.1.5 December 2005

4.1.3 Driver construction & testing January 2004 December 2005 80 %

4.1.4 Full scale prototype design January 2005 June 2005 Finished

4.1.5 Full scale prototype construction January 2005 December 2005 90%

4.2 Chopper line (CERN)

4.2.1 Dump design January 2004 June 2004 Finished

4.2.2 Dump construction January 2005 June 2005 20% December 2005

4.3 Chopper structure B (RAL)

4.3.1 Pre-prototype design and test January 2004 June 2005 Finished

4.3.2 Prototype design January 2005 December 2005 40 %

changeschanges

CERN : CERN : • Driver conception Driver conception • Skip the phase of pre-prototype Skip the phase of pre-prototype

RAL : RAL : • Beam dynamics (frequency,energy) Beam dynamics (frequency,energy) • Chopping mechanism (localised dump, quad) Chopping mechanism (localised dump, quad)

AchievementsAchievements

Table of Chopper characteristics Chopper A (CERN) Chopper B (RAL) Fast Fast Slow† Rise/fall time < 2 nsec ≤ 2 nsec ≤ 15 ns Max. rep rate 50 MHz 2.6 MHz 1.3 MHz Max. voltage/target 250 V/500V 1400V / 2200V ≤ 6kV Flexibility Min 3 pulses 7 – 15 ns

200 ns – 100 us

Chopping effectiveness (calculated)

99.7% 99.0 %

Emittance growth of the un-chopped beam

8% 8% (New 3 MeV MEBT design)‡

† Simulation only. ‡ Effect of residual chopper fields not included

the deliverablesthe deliverables

WBS # Title Due date in Annex 1 Status Revised delivery date

4.1.1 Chopper A design report June 2005 delayed December 2005

4.1.2 Intermediate test report March 2005 Waiting for task 4.1.5 March 2006

4.2.2 Dump design report June 2005 pending October 2005

4.3.1 Chopper B intermediate report June 2005 Delivered July2005

CollaborationCollaboration 1. Activity at RAL re-design of the chopper line optics - based on the idea of 1. Activity at RAL re-design of the chopper line optics - based on the idea of

‘amplification’ of chopper beam deflection with a downstream defocusing quadrupole‘amplification’ of chopper beam deflection with a downstream defocusing quadrupole . . This is an example of a CERN based idea influencing the RAL design effort.This is an example of a CERN based idea influencing the RAL design effort.

   2. Activity at RAL regarding 2. Activity at RAL regarding the modification to the design of RAL slow wave structure the modification to the design of RAL slow wave structure

C, to enable it to fit into the bore of a quadrupoleC, to enable it to fit into the bore of a quadrupole - prompted by the possibility of - prompted by the possibility of testing on the CERN front-end test facility. An example of a CERN based requirement testing on the CERN front-end test facility. An example of a CERN based requirement influencing RAL design. influencing RAL design.

   3. Activity at CERN regarding the design of the new FET based 3. Activity at CERN regarding the design of the new FET based bipolar pulserbipolar pulser. This . This

approach came about as a result of the cross fertilisation of ideas between CERN approach came about as a result of the cross fertilisation of ideas between CERN and RAL.  Example of RAL helping the CERN effort.and RAL.  Example of RAL helping the CERN effort.

   4. Activity during the last HIPPI meeting at Abingdon (and subsequently), regarding a 4. Activity during the last HIPPI meeting at Abingdon (and subsequently), regarding a

meeting between J. Hares (Director & Chief Designer, Kentech Instruments Ltd, UK), meeting between J. Hares (Director & Chief Designer, Kentech Instruments Ltd, UK), CERN and RAL representatives with the purpose of discussing the possibility of CERN and RAL representatives with the purpose of discussing the possibility of alternative pulse generator designs for the CERN chopper. This activity has also alternative pulse generator designs for the CERN chopper. This activity has also (subsequently) involved discussions with Bill Foster regarding a Fermilab linac (subsequently) involved discussions with Bill Foster regarding a Fermilab linac upgrade scheme. This is an example of a RAL based connection with a specialist upgrade scheme. This is an example of a RAL based connection with a specialist manufacturer being utilised by a CERN based collaborator (and a FERMILAB based manufacturer being utilised by a CERN based collaborator (and a FERMILAB based colleague).colleague).

Ingredients of the working Ingredients of the working packagepackage

Chopper (plates and drivers)Chopper (plates and drivers)

Beam dynamics Beam dynamics

Beam lines Beam lines

today’s program today’s program Status of the CERN chopper (25’+5’) Status of the CERN chopper (25’+5’) - - M.PaoluzziM.Paoluzzi Status of the RAL ‘Fast-Slow’ beam chopper development Status of the RAL ‘Fast-Slow’ beam chopper development

programme (25’+5’) - programme (25’+5’) - M. Clarke-GaytherM. Clarke-Gayther The FETS: Front End Test Stand (15’+5’) – The FETS: Front End Test Stand (15’+5’) – D. FindlayD. Findlay Beam dynamics studies and design options for the RAL Beam dynamics studies and design options for the RAL

FETS chopper line (10’+5’) - FETS chopper line (10’+5’) - G.BellodiG.Bellodi Status of the CERN Chopper line (10’+5’) - Status of the CERN Chopper line (10’+5’) - A.LombardiA.Lombardi

Design of a rebunching cavity for the RAL FETS chopper Design of a rebunching cavity for the RAL FETS chopper

line (10’) - line (10’) - CC. Plostinar. Plostinar