IFMIF mini-workshop on Beam Instrumentation. Ciemat, Madrid (Spain) 2-3 July 2007

Transcription

1 IFMIF BIW Agenda IFMIF mini-workshop on Beam Instrumentation Ciemat, Madrid (Spain) 2-3 July 2007 Monday, 2 july :00 J. Sanchez Welcome message Today 9:10 A. Mosnier (CEA-Saclay) Instrumentation needs for the IFMIF accelerator 9:30 P. Ausset (IPN-O) Overview of diagnostics on IPHI and SPIRAL2 10:10 K. Hanke (CERN) Diagnostics foreseen for LINAC4 10:50 Coffee break 11:20 Layout and experiences of high current beam P. Forck (GSI) diagnostics at GSI-UNILA 12:00 I. Mardor (Soreq) Overview of beam diagnostics at SARAF 12:30 Lunch 14:00 J.L. Vignet (Ganil) Beam Profile Measurement at Ganil 14:30 C. Olivetto (IPHC-Strasburg) Diagnostic plate and emittance meter for Spiral2 15:10 L. Weisman (Soreq) Beam halo monitor for Saraf 15:40 H. Sakaki (J-Parc) Beam diagnostics used on J-PARC linac 16:20 Coffee break 16:50 Visit to TJ-II and plasma diagnostics Alban Mosnier IFMIF BIW, 2-3 July 2007 page 1

2 Tentative Agenda Tomorrow Tuesday, 3 july :00 Discussion: Beam commissioning and operation (chair: A. Facco) short introductive presentation H. Sakaki J-Parc commissioning Time limits due to thermal shock damage in the Ciemat materials 10:30 Coffee break 10:50 Discussion: Preliminary list of diagnostics and specifications for Ifmif (chair: A. Mosnier) A. Ibarra short introductive presentation Ciemat (for E. Surrey) UKAEA studies on HEBT IFMIFDiagnostics 13:00 Lunch 14:30 Conclusions Alban Mosnier IFMIF BIW, 2-3 July 2007 page 2

3 Importance of beam diagnostics... essential for tune-up, start-up, commissioning, continuous monitoring, interlocks Alban Mosnier IFMIF BIW, 2-3 July 2007 page 3

4 on the web page of J-PARC LINAC Status IS/RFQ section: LEBT:SCT01 MEBT1:SCT01~SCT05 DTL section:dtl1:01~dtl3:sct01 SDTL section:s01b:sct00 - S15B:SCT00 A0BT section:acs03a:sct00 ~ ACS11B:SCT01 L3BT section:l3bt:sct06 ~L3BT:SCT14 Alban Mosnier IFMIF BIW, 2-3 July 2007 page 4

5 Instrumentation needs for the IFMIF linac Beam Power ~ 5MW in a single IFMIF accelerator This power would destroy any interceptive diagnostics ~ MW in the IFMIF/EVEDA Linac prototype Pulsed mode operation at low duty cycle during tune-up and commissioning New kinds of non-interceptive diagnostics must be developed intensified CCD analyses, spectroscopy analyses, beam halo monitors, quadrupole moment monitor, etc Specific tools developed for the measurement of the transverse profiles of high power proton beams include: 1) Conventional wire scanner systems for low duty factor, pulsed beam operation; 2) Measurements of back scattered protons or γ ray production to cross check the measurement of the current in the wire in the temperature range of the wire below thermo-ionic emission; 3) beam induced fluorescence measurements (under high average power beam pulsed mode and CW operation) Alban Mosnier IFMIF BIW, 2-3 July 2007 page 5

6 Diagnostics considered, is it enough? Beam Visualisation video-camera Beam Current Monitor DCCT (toroid) + ACCT Beam Loss Monitor thermocouples neutron detector Beam Stop movable Faraday cup Emittance measurement Allison scanner Species fraction analyzer Doppler shift analysis in residual gas Space Charge compensation 4 Grid analyser DC toroid on HV cable Thermocouples Injector (source and LEBT) Spectrometer + OF Cameras Movable CF Neutron detector EMU, 4GA Cone Cameras ACCT Thermocouples Alban Mosnier IFMIF BIW, 2-3 July 2007 page 6

7 Several remarks (R. Gobin) Important to limit LEBT length to minimize emittance growth DCCT could be easily replaced ACCT and cone are important at the entrance of RFQ Beam power is too high (in CW mode) for Wire Scanner Beam steering with non interceptive profiler (secondary particles analysis) Cameras essential to monitor beam size and beam centroid Neutron detector and thermocouples give information on beam loses Species fraction could be permanently measured with Doppler shift analysis optic fiber + dedicated optic devices (to be tested) Alban Mosnier IFMIF BIW, 2-3 July 2007 page 7

8 Goal Beam Image Beam Current Monitor Beam Position Monitor Transv. Profile Monitor Bunch Shape Monitor Type View screen (or simple camera in LEBT) toroid (if fast bunch length) also beam phase monitor SEM-grid Wire Scanner (WS) beam induced fluorescence residual gas monitor transverse rf modulation Preliminary list non-interceptive x x x x Emittance-meter Faraday cup (fast) with energy degrader Beam Loss Monitor Beam energy pepperpot, slit scanner, Allison type? current & bunch length monitor? for RF-phase & amplitude setting neutron detector Time of Flight phase monitor x Beam halo monitor? Saraf development.. Alban Mosnier IFMIF BIW, 2-3 July 2007 page 8

9 Beam Loss Monitors (SNS) PhotoMultiplier Tube covered with scintillator sensitive to neutrons sensitivity controlled by High Voltage ionization chambers (filled with argon) detect X-ray and γ radiation (Argon) (Photomultiplier tubes) Alban Mosnier IFMIF BIW, 2-3 July 2007 page 9

10 wire scanner Drift Tube Linac Alvarez-type DTL (reference) inside DTL tank BPositionM + Correctors in empty drift tubes modified lattice FODO to FFODDO (SNS-like) intertank regions BCurrentM, WireScanner, EnergyDegrader/FaradayCup Superconducting DTL (alternative option) BCurrentM, BPositionM, BLossM Profile Monitor? WS not recommended and Laser Scanner doesn t work Alban Mosnier IFMIF BIW, 2-3 July 2007 page 10

11 Techniques for setting RF phase & amplitude of DTL tanks (SNS) 1. acceptance scan using EnergyDegrader/FaradayCup located after each tank degrader thickness: chosen to absorb beam particles with energy just below the nominal acceptance. phase & amplitude: determined by comparing the transmitted current with beam dynamics simulations 2. phase scan using BPMs: beam phase (or difference between 2 BPMs) measured as a function of the tank phase & amplitude; model-based fit to obtain A, ϕ, Energy FC Alban Mosnier IFMIF BIW, 2-3 July 2007 page 11

12 RF phase & amplitude setting for SC Linac (SNS) time-of-flight based phase scan. difference in beam arrival phase between two downstream BPMs as a function of the SCL RF cavity phase (resulting phase difference nearly sinusoidal) and is readily fit to input energy, accelerating gradient & relative beam-cavity phase obtained from a fit of the phase difference The method relies on the absolute phase measurement capability of the beam position monitor system (demonstrated at SNS) Alban Mosnier IFMIF BIW, 2-3 July 2007 page 12

13 Bunch Shape Measurement used to verify beam quality, to set parameters of the accelerating field, to estimate longitudinal halo and longitudinal emittance. conversion of the longitudinal charge distribution into a spatial distribution of low energy secondary electrons through transverse RF modulation not needed for deuteron beams: system used for separation of the electrons originated from H- dissociation Alban Mosnier IFMIF BIW, 2-3 July 2007 page 13

14 D-plate for IFMIF? SNS D-Plate: A Collection of Diagnostics for Commissioning up to the DTL Tank 1 (7.5 MeV) Beam position monitors Emittance (slit-collector) Carbon-fiber wire scanners Beam accounting system Beam current monitor Video system Halo Scrapers Beam stop Beam loss monitors Neutron detectors Faraday cup Bunch shape monitor Top level EPICS screen for D-Plate LANL D-plate installed at ORNL Alban Mosnier IFMIF BIW, 2-3 July 2007 page 14

15 D-plate for SPIRAL2-2 Beam profile monitors: SEM & gas residual - 1 Emittancemeter - 1 DCCT - 1 Faraday cup - 1 FCT (Fast current transformer) - 1 bunch length measurement - ToF measurement Pick-up - Beam Position Monitor SPIRAL2 Injector Test Bench Alban Mosnier IFMIF BIW, 2-3 July 2007 page 15

16 D-plate for SARAF - 2 phase probes (phase & TOF measurements) - 1 current transformer - 1 beam position monitor - 1 emittance slit and wire system - 1 fast faraday cup (bunch length measurement) - 1 degrader & faraday cup system (energy spread measurement) - 1 beam halo monitor beam dump :10 kw Cu part suitable for the RFQ exit + an additional Heavy Metal (HM) 20 kw part for the PSM (Prototype SC Module) Alban Mosnier IFMIF BIW, 2-3 July 2007 page 16

17 Special Diagnostic just before the Li Target Specific development for IFMIF Design : the beam transverse profile monitor at the end of HEBT vertical beam tapering ~ 1 cm variable horizontal width 10 to 20 cm 5 cm 20 cm CEA-Saclay in charge of the development of this non-interceptive beam profile monitor (IFMIF design phase) Alban Mosnier IFMIF BIW, 2-3 July 2007 page 17

18 Beam diagnostics are essential components for the commissioning and the operation of an accelerator and especially for IFMIF with its very huge intensity... Alban Mosnier IFMIF BIW, 2-3 July 2007 page 18