, 2003, A dedicated proton accelerator for 1 p-physics at the future GSI Demands facilities for Beam Diagnostics

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1 Beschleunigerinstrumentierung und Strahldiagnostik University Frankfurt Sommersemester 2014 Dr. Peter Forck Gesellschaft für Schwerionenforschnung (GSI) und University Frankfurt, 2003, A dedicated proton accelerator for 1 p-physics at the future GSI Demands facilities for Beam Diagnostics

2 Demands on Beam Diagnostics Diagnostics is the organ of sense for the beam. It deals with real beams in real technical installations including all imperfections. Four types of demands leads to different installations: Quick, non-destructive measurements leading to a single number or simple plots. Used as a check for online information. Reliable technologies have to be used. Example: Current measurement by transformers. Instruments for daily check, malfunction diagnosis and wanted parameter variation. Example: Profile measurement, in many cases intercepting i.e destructive to the beam Complex instruments for severe malfunctions, accelerator commissioning & development. The instrumentation might be destructive and complex. Example: Emittance determination. Instruments for automatic, active beam control. Example: Closed orbit feedback using position measurement by BPMs. A clear interpretation of the results is a important design criterion. Non-destructive ( non-intercepting ) methods are preferred: The beam is not influenced The instrument is not destroyed., 2003, A dedicated proton accelerator for 2 p-physics at the future GSI Demands facilities for Beam Diagnostics

3 The Role of Beam Diagnostics The cost of diagnostics is about 3 to 10 % of the total facility cost: 3 % for large accelerators or accelerators with standard technologies 10 % for versatile accelerators or novel accelerators and technologies. Cost Examples: The amount of man-power is about 10 to 20 %: very different physics and technologies are applied technologies have to be up-graded, e.g. data acquisition and analysis accelerator improvement calls for new diagnostic concepts., 2003, A dedicated proton accelerator for 3 p-physics at the future GSI Demands facilities for Beam Diagnostics

4 Relevant physical Processes for Beam Diagnostics Electro-magnetic influence by moving charges: classical electro-dynamics, voltage and current meas., low and high frequencies Examples: Faraday cups, beam transformers, pick-ups Emission of photon by accelerated charges: (only for high relativistic electrons and p) classical electro-dynamics, optical techniques (from visible to x-ray) Example: Synchrotron radiation monitors Interaction of particles with photons: optics, lasers, optical techniques, particle detectors Examples: laser scanners, short bunch length measurement, polarimeters Coulomb interaction of charged particles with matter: atomic and solid state physics, current measurement, optics, particle detectors Examples: scintillators, viewing screens, ionization chambers, residual gas monitors Nuclear- or elementary particle physics interactions: nuclear physics, particle detectors Examples: beam loss monitors, polarimeters, luminosity monitors And of cause accelerator physics for proper instrumentation layout. Beam diagnostics deals with the full spectrum of physics and technology, this calls for experts on all these fields and is a challenging task!, 2003, A dedicated proton accelerator for 4 p-physics at the future GSI Demands facilities for Beam Diagnostics

5 Beam Quantities and their Diagnostics I LINAC & transport lines: Single pass Synchrotron: multi pass Electrons: always relativistic Protons/Ions: non-relativistic for E kin < 1 GeV/u Depending on application: Low current high current Overview of the most commonly used systems: Beam quantity LINAC & transfer line Synchrotron Current I General Special Transformer, dc & ac Faraday Cup Particle Detectors Transformer, dc & ac Pick-up Signal (relative) Profile x width General Screens, SEM-Grids Wire Scanners, OTR Screen Position x cm Transverse Emittance ε trans Special General Special General Special MWPC, Fluorescence Light Pick-up (BPM) Using position measurement Slit-grid Quadrupole Variation Pepper-Pot Residual Gas Monitor Wire Scanner, Synchrotron Light Monitor Pick-up (BPM) Residual Gas Monitor Wire Scanner Transverse Schottky, 2003, A dedicated proton accelerator for 5 p-physics at the future GSI Demands facilities for Beam Diagnostics

6 Beam Quantities and their Diagnostics II Beam quantity LINAC & transfer line Synchrotron Bunch Length Δφ General Special Pick-up Secondary electrons Pick-up Wall Current Monitor Streak Camera Electro-optical laser mod. Momentum p and Momentum Spread Δp/p Longitudinal Emittance ε long Tune and Chromaticity Q, ξ General Special General Special General Special Pick-ups (Time-of-Flight) Magnetic Spectrometer Buncher variation Magnetic Spectrometer Beam Loss r loss General Particle Detectors Polarization P General Special Pick-up (e.g. tomography) Schottky Noise Spectrum Pick-up & tomography Exciter + Pick-up Transverse Schottky Spectrum Particle Detectors Laser Scattering (Compton scattering) Luminocity L General Particle Detectors Destructive and non-destructive devices depending on the beam parameter. Different techniques for the same quantity Same technique for the different quantities., 2003, A dedicated proton accelerator for 6 p-physics at the future GSI Demands facilities for Beam Diagnostics

7 Beam Diagnostics for LEBT at GSI UNILAC The measurement at a LEBT (Low Energy Beam Transport) comprises of: Current, profile, emittance, charge composition Example: LEBT at GSI UNILAC Length: 10.8 m Beam current Emittance Cup Beam profile Emittance Beam current, 2003, A dedicated proton accelerator for 7 p-physics at the future GSI Demands facilities for Beam Diagnostics

8 Example: Diagnostics Bench for the Commissioning of an RFQ, 2003, A dedicated proton accelerator for 8 p-physics at the future GSI Demands facilities for Beam Diagnostics

9 Typical Installation of a Diagnostics Device Modern trend: High performance ADC & digital signal processing accelerator tunnel: local electronics room: control room: action of the beam to the detector low noise pre-amplifier and first signal shaping analog treatment, partly combining other parameters digitalization, data bus systems (GPIB, VME, cpci...) visualization and storage on PC parameter setting of the beam and the instruments, 2003, A dedicated proton accelerator for 9 p-physics at the future GSI Demands facilities for Beam Diagnostics

10 Example: Graphical User Interface for Beam Position Monitors The result helps to align the accelerator! Some experimental device parameters are also shown to prove the functionality., 2003, A dedicated proton accelerator for 10 p-physics at the future GSI Demands facilities for Beam Diagnostics

11 Outline of the Lecture The ordering of the subjects is oriented by the beam quantities: Current measurement: Transformers, cups, particle detectors Profile measurement: Various methods depending on the beam properties Transverse emittance measurement: Destructive devices, determination by linear transformations Pick-ups for bunched beams: Principle and realization of rf pick-ups, closed orbit and tune measurements Measurement of longitudinal parameters: Beam energy with pick-ups, time structure of bunches for low and high beam energies, longitudinal emittance Beam loss detection: Secondary particle detection for optimization and protection It will be discussed: The action of the beam to the detector, the design of the devices, generated raw data, partly analog electronics, results of the measurements. It will not be discussed: Detailed signal-to-noise calculations, analog electronics, digital electronics, data acquisition and analysis, online and offline software... General: Standard methods and equipment for stable beams with moderate intensities., 2003, A dedicated proton accelerator for 11 p-physics at the future GSI Demands facilities for Beam Diagnostics

12 Goal of the Lecture Signal generation Valid interpretation The goal of the lecture should be: Understanding the signal generation of various device Showing examples for real beam behavior Enabling a correct interpretation of various measurements., 2003, A dedicated proton accelerator for 12 p-physics at the future GSI Demands facilities for Beam Diagnostics

13 Vorlesung Beschleunigerinstrumentierung und Strahldiagnostik Übersicht: Die grundlegenden Verfahren zur Diagnose von Ionen- und Elektronenstrahlen werden in der Vorlesung besprochen. Die Diskussion praktischer Realisierungen steht dabei im Vordergrund. Ein Ausblick auf neuere Entwicklungen runden das Thema ab. Termine und Themen: Program for the Lecture 15. April: Methoden der Strom-Messung BSc ab 5 Semester und MSc aller Semester 29. April: Methoden der Profilmessung I Grundkenntnisse in Beschleuniger-Physik erwünscht 6. Mai: Methoden der Profilmessung II 2 Credit Points bei Teilnahme an den Übungen 20. Mai: Verfahren der Emittanzmessung Auf Wunsch Vortragssprache Englisch 3. Juni: Beam Position Monitore I 10. Juni: Beam Position Monitore II 24. Juni: Messung longitudinaler Parameter 1. Juli: Strahlverlust Messungen 15. Juli: Besichtigung GSI, weitere Themen Zielgruppe:, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

14 Literature on Beam Diagnostics K. Wille, The Physics of Particle Accelerators, Oxford Uni. Press (2000). V. Smaluk, Particle Beam Diagnostics for Accelerators: Instruments and Methods, VDM Verlag Dr. Müller, Saarbrücken D. Brandt (Ed.), Beam Diagnostics for Accelerators, Proc. CERN Accelerator School CAS, Dourdan, CERN (2009) see P. Strehl, Beam Instrumentation and Diagnostics, Springer-Verlag, Berlin H. Koziol, Beam Diagnostic for Accelerators, Proc. CERN Accelerator School CAS, University Jyväskylä, Finland, p. 565 CERN (1994), see J. Bosser (Ed.), Beam Instrumentation, CERN-PE-ED , Rev P. Forck, JUAS Lecture Notes on Beam Diagnostics, see www-bd.gsi.de/conf/juas/juas.html. 14, 2003, A dedicated proton accelerator for 14 p-physics at the future GSI Demands facilities for Beam Diagnostics

15 3 rd Generation Light Sources: Synchrotron-based with E electron 1 8 GeV Excurse: 3 rd Generation Light Sources Light from undulators& wigglers, dipoles, with E < 10 kev (optical to deep UV) Soleil, Paris, E electron = 2.5 GeV, C = 354 m Users in: Biology (e.g. protein crystallography) Chemistry (e.g. observation of reaction dynamics) material science (e.g. x-ray diffraction) Basic research in solid state and atomic physics Unique setting: intense, broad-band light emission (monochromator for wavelength selection) National facilities in many counties, some international facilities., 2003, A dedicated proton accelerator for 15 p-physics at the future GSI Demands facilities for Beam Diagnostics

16 Excurse: Example Synchrotron Light Facility ALBA 3 rd generation Spanish national synchrotron light facility in Barcelona Layout: Beam lines: up to 30 Electron energy: 3 GeV Top-up injection Storage ring length: 268 m Max. beam current: 0.4 A Commissioning in 2011 Talk by Ubaldo Iriso: at DIPAC 2011, adweb.desy.de/mpy/dipac2011/html/sessi0n.htm see also , A dedicated proton accelerator for 16 p-physics at the future GSI Demands facilities for Beam Diagnostics

17 Excurse: Example Synchrotron Light Facility ALBA 3 rd generation Spanish national synchrotron light facility in Barcelona Layout: Beam lines: up to 30 Electron energy: 3 GeV Top-up injection Storage ring length: 268 m Max. beam current: 0.4 A LINAC 100 MeV Commissioning in 2011 Booster 100 MeV 3 GeV Storage Ring: 3 GeV From U. Iriso, ALBA, 2003, A dedicated proton accelerator for 17 p-physics at the future GSI Demands facilities for Beam Diagnostics

18 Excurse: Example ALBA: Current Measurement BTS 2 FCT From U. Iriso, ALBA FCT DCCT FCUP AE BCM SR 1 FCT 1 DCCT 1 AE BOOSTER 1 FCT 1 DCCT 1 AE LTB 1 FCT 1 FCUP 3 BCM Beam current: Amount of electrons accelerated, transported and stored Several in transport lines One per ring Abbreviation: FCT: Fast Current Transformer DCCT: dc transformer FCUP: Faraday Cup AE: Annular Electrode BCM: Bunch Charge Monitor Remark: AE: Annular Electrode i.e. circular electrode acting like a high frequency pick-up, 2003, A dedicated proton accelerator for 18 p-physics at the future GSI Demands facilities for Beam Diagnostics

19 Excurse: 4 th Generation Light Sources Flash, Hamburg 4 th Generation Light Sources: LINAC based, single pass with large energy loss E electron 1 18 GeV, coherent light from undulator, E < 1000 kev range, short pulse Europe: Germany, Italy, Netherlands, Switzerland, America: USA, Asia: China, Japan New accelerator technology for intense, short electron pulses:, 2003, A dedicated proton accelerator for 19 p-physics at the future GSI Demands facilities for Beam Diagnostics

20 Excurse: FLASH (Hamburg) as Example of 4 th Gen. Light Sources Flash, Hamburg Large scale European project: XFEL at DESY in Hamburg E electron 17 GeV, length 3.4 km, 2003, A dedicated proton accelerator for 20 p-physics at the future GSI Demands facilities for Beam Diagnostics

21 Excurse: Electron Accelerators for Cancer Treatment LINAC based x-ray generation for treatment (i.e. destruction) of degenerated cells E electron 20 MeV, send on thick target to produce hard x-rays, which are send to the patient Standard radio therapy installation at each larger city traget collimator electrons LINAC e - gun x-rays LINAC, 2003, A dedicated proton accelerator for 21 p-physics at the future GSI Demands facilities for Beam Diagnostics

22 Excurse: Proton Cyclotrons for Isotope Production Cyclotron for protons, deuterons and Helium, with E proton MeV thick target to produce shorted lived isotopes (followed by bio-chemical molecule modification) for medical diagnostics (e.g. scintigraphy, Positron Emission Tomography PET, radio-therapy) Short lived isotopes installation at each larger city, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

23 Excurse: Proton Facilities for Neutron Production Example: Spallation Neutron Source SNS in Oak Ridge, Tennessee USA, commissioning 2007 LINAC for acceleration: length L = 335 m, E proton = 1 GeV, 60 Hz operation Storage Ring for compression: C = 248 m, N p, pulse length t pulse = 700 ns Goal: high intensities on liquid mercury target, power 1 MW Users in: Material science, solid state physics, biology Storage ring LINAC Comparable new project: European Spallation Source in Lund, Schweden, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

24 Excurse: CERN Facility for High Energy Physics LHC SPS CERN in Geneva as an European facility 1959: Commissioning Proton Synchrotrons PS length C= 628 m, E kin = 25 GeV 1976: Comm. of Super Proton Synchrotron SPS length C= 6.4 km, E kin = 450 GeV 1989: Large Electron Position collider LEP C= 27 km E kin = 200 GeV (electrons&positions) Comm. Large Hadron Collider LHC C= 27 km, E kin = 7 TeV LHC tunnel with sc magnets PS, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

25 GSI Heavy Ion Research Center German national heavy ion accelerator facility in Darmstadt Accelerators: Acceleration of all ions LINAC: up to 15 MeV/u Synchrotron: up to 2 GeV/u Research area: Nuclear physics 60 % Atomic physics 20 % Bio physics (e.g cell damage) incl. cancer therapy 10 % Material research 10 % Extension by international FAIR facility GSI is one of 18 German large scale research centers., 2003, A dedicated proton accelerator for 25 p-physics at the future GSI Demands facilities for Beam Diagnostics

26 The Accelerator Facility at GSI Ion Sources: all elements UNILAC FRS Synchrotron, Bρ=18 Tm E max p: 4.7 GeV U: 1 GeV/u Achieved e.g.: Ar 18+ : U 28+ : U 73+ : SIS UNILAC: all ions p U : 3 12 MeV/u, 50 Hz, max. 5 ms Up to 20 ma current ESR ESR: Storage Ring, Bρ=10 Tm Atomic & Plasma Physics Radiotherapy Nuclear Physics, 2003, A dedicated proton accelerator for 26 p-physics at the future GSI Demands facilities for Beam Diagnostics

27 The Accelerator Facility at GSI Ion Sources: all elements UNILAC Synchrotron: Current: 2 DCCT, 1 ACCT, 1 FCT Profile: 1 SEM-Grid, 1 IPM, 1 Screen Position: 16 BPM Tune, mom. spread: 1 Exciter + BPM 1 Schottky SIS LINAC: Current: 52 transformers, 30 Faraday-Cups Profile: 81 SEM-Grids, 6 BIF Position & phase: 25 BPM Trans. emittance: 9 Slit-Grid, 1 pepper-pot Long. emittance: 3 devices of different type ESR FRS Transport Lines: Current: 8 FCT 15 Part. Detec. Profile: 10 SEM-Grid 26 MWPC 18 Screens Position: 8 BPM, 2003, A dedicated proton accelerator for 27 p-physics at the future GSI Demands facilities for Beam Diagnostics

28 UNILAC at GSI: Overview RFQ, IH1, IH2 Alvarez DTL Single Gap Resonators Transfer to Synchrotron MEVVA MUCIS HLI: (ECR,RFQ,IH) All ions, high current, 5 ms@50 Hz, 36&108 MHz f rf = 36 MHz f rf = 108 MHz Alvarez DTL To SIS Foil Stripper PIG 2.2 kev/u β = RFQ IH1 IH2 120 kev/u β = U 4+ U MeV/u β = Gas Stripper 10mm 11.4 MeV/u β = 0.16 Constructed in the 70th, Upgrade 1999, Injector for FAIR ion operation, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

29 UNILAC at GSI: Current Measurement Faraday Cup: for low current measurement and beam stop, total 30 Transformer ACCT: for current measurement and transmission control total 52 device Transfer to Synchrotron MEVVA MUCIS HLI: (ECR,RFQ,IH) All ions, high current, 5 ms@50 Hz, 36&108 MHz Alvarez DTL To SIS Foil Stripper PIG 2.2 kev/u β = RFQ IH1 IH2 120 kev/u β = U 4+ U 28+ Gas Stripper 1.4 MeV/u β = MeV/u β = 0.16 Constructed in the 70th, Upgrade 1999, further upgrades in preparation, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

30 The Accelerator Facility at GSI Ion Sources: all elements UNILAC FRS Synchrotron, Bρ=18 Tm E max p: 4.7 GeV U: 1 GeV/u Achieved e.g.: Ar 18+ : U 28+ : U 73+ : SIS UNILAC: all ions p U : 3 12 MeV/u, 50 Hz, max. 5 ms Up to 20 ma current ESR ESR: Storage Ring, Bρ=10 Tm Atomic & Plasma Physics Radiotherapy Nuclear Physics, 2003, A dedicated proton accelerator for 30 p-physics at the future GSI Demands facilities for Beam Diagnostics

31 acceleration GSI Heavy Ion Synchrotron: Overview Dipole, quadrupole, rf cavity Important parameters of SIS-18 Important parameters of SIS-18 Circumference 216 m Circumference Inj. type 216 m Multiturn injec- tion Inj. type Energy range Energy range Acc. RF Acc. RF Harmonic 11 MeV 2 GeV MHz 4 (= # bunches) Bunching factor Ramp duration Multiturn 11 MeV/u 2 GeV/u MHz 4 (= # bunches) Bunching factor Ramp duration s s Ion range (Z) 1 92 (p to U) Ion range (Z) 1 92 (p to U) extrac- tion Dipole, quadrupole, transfer line commissioning 1991, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

32 GSI Heavy Ion Synchrotron: Current Measurement acceleration ACCT: injected current MHz Important parameters of SIS-18 Circumference 216 m Inj. type Multiturn Energy range 11 MeV 2 GeV DCCT: circulating current khz FCT: bunch structure MHz injection Acc. RF MHz Harmonic 4 (= # bunches) Bunching factor extraction Faraday Cup: beam dump Ramp duration s Ion range (Z) 1 92 (p to U), 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics

33 Excurse: GSI and FAIR in Future GSI accelerator: all ions high intensity for 1 GeV/u production of rare isotopes beam cooling (electron, stochastic, laser) FAIR: extension of program + antiprotons GSI FAIR Main physics activities at FAIR: Nuclear Structure with in-flight Rare Isotope Beams Hadron Physics at 30 GeV/u heavy ions Hadron Physics with antiprotons up to 14 GeV Atomic Physics with RIBs and antiprotons Plasma, Biophysics and Material Science, 2003, A dedicated proton accelerator for p-physics at the future GSI Demands facilities for Beam Diagnostics