Impedance & Instabilities
|
|
- Philomena Edith Turner
- 5 years ago
- Views:
Transcription
1 Impedance & Instabilities The concept of wakefields and impedance Wakefield effects and their relation to important beam parameters Beam-pipe geometry and materials and their impact on impedance An introduction to beam instabilities (including ion effects) Rainer Wanzenberg CAS Vacuum for Particle Accelerator June 7, 2017 Hotel Orenas Slott, Glumslov, Sweden
2 The concept of Wakefields and Impedance Wake Field = the track left by a moving body (as a ship) in a fluid (as water); broadly : a track or path left Impedance = Fourier Transform (Wake Field) Rainer Wanzenberg Impedance & Instabilities June 2017 Page 2
3 Electric Field of a Bunch Point charge in a beam pipe Gaussian Bunch, Step out transition Opening angle Wakefields Rainer Wanzenberg Impedance & Instabilities June 2017 Page 3
4 Geometric wakefields and resistive wall wakes Geometric Wake Resistive Wall Wake Material roughness, Oxide layers σ = σ = ( Ωm) σ = (1 6 Ω m = 10 ( Ωm) 6 ( Ωm) 6 Ω mm m Cu Al Steel 2 ) M. Dohlus, M.I. Ivanyan, V.M. Tsakanov Surface Roughness Study for the TESLA-FEL, DESY-TESLA-FEL Rainer Wanzenberg Impedance & Instabilities June 2017 Page 4
5 Short and Long Range Wakefields Example: small cavity Transient effect: within one bunch, head interacts with the tail Long range wakefields: One or many modes are excited in the cavity bunch interacts with other bunches Rainer Wanzenberg Impedance & Instabilities June 2017 Page 5
6 Effects on a test charge Change of energy Bunch charge q 1 Test charge q 2 depends on the total bunch charge q 1 q 2 s q 1 Equation of motion q 1 : q 2 : z=c t z = c t - s Rainer Wanzenberg Impedance & Instabilities June 2017 Page 6
7 Effects on a test charge (cont.) Lorentz force: r F = q 2 r r ( E + c u B) z r q 2 The electric and magnetic fields are generated by the bunch charge q 1 test charge q 2 change of energy transverse kick Bunch: q 1 Rainer Wanzenberg Impedance & Instabilities June 2017 Page 7
8 Approximations Numerical calculation of a wakefield of a Gaussian bunch traversing a cavity The concept of a Wakefield assumes the Rigid Beam Approximation The wakefield does not affect the motion of the beam The wakefield does not affect the motion of the test charge (only the energy or momentum change is calculated) The interaction of the beam with the environment is not self consistent. Nevertheless, one can use results from wake field calculations for a turn by turn tracking code - sometimes cutting a beam into slices. Rainer Wanzenberg Impedance & Instabilities June 2017 Page 8
9 Wakefield effects and their relation to important beam parameters Beam Parameter: Total bunch charge q 1 Bunch length (and shape) q 2 s q 1 Transverse dimensions (Emittance, Beta-function) Number of bunches Total beam current Synchrotron tune Betatron tune Damping time (Synchrotron Rad.) Chromaticity Transient effects: Wakefield depends on bunch charge and charge distribution geometry change or material properties Rainer Wanzenberg Impedance & Instabilities June 2017 Page 9
10 Example: Beam parameters of PETRA III Design Parameter PETRA III Energy / GeV 6 Circumference /m 2304 RF Frequency / MHz 500 RF harmonic number 3840 RF Voltage / MV 20 Experimental Hall Momentum compaction Synchrotron tune Total current / ma 100 Number of bunches Bunch population / Bunch separation / ns Undulators Emittance (horz. / vert.) /nm 1.2 / 0.01 Bunch length / mm 12 Damping time H/V/L / ms 16 / 16 / 8 RF system Coupled bunch instabilities threshold current ~ 10 ma powerful broadband feedback neccessary Rainer Wanzenberg Impedance & Instabilities June 2017 Page 10
11 Wakepotential Longitudinal Wakepotential: t (Unit V/C) Electric field of a Gaussian bunch time of the head: t = z/c test charge tail: t = (s+z)/c (or test charge) energy loss/gain: E = e q1 Wz( s) s z Rainer Wanzenberg Impedance & Instabilities June 2017 Page 11
12 Transverse Wakepotential Lorentz Force Longitudinal Wakepotential Transverse Wakepotential Change of momentum of a test charge q 2 Kick on an electron (q 2 ) due to the bunch charge q 1 beam energy Rainer Wanzenberg Impedance & Instabilities June 2017 Page 12
13 Example: TESLA cavity cavity length ~ 1 m rms bunch length σ = 50 µm σ = 250 µm σ = 1 mm E= e 1 nc (-20 kv/nc) = 20 kev Energy spread: 20 kev / 20 MeV = 0.1 % s/σ assuming an accelerating gradient of 20 MV/m Rainer Wanzenberg Impedance & Instabilities June 2017 Page 13
14 Wake: point charge versus bunch Longitudinal Wakepotential The fields E and B are generated by the charge distribution ρ and the current density j. They are solutions of the Maxwell equations and have to obey several boundary conditions. Line charge density Rainer Wanzenberg Impedance & Instabilities June 2017 Page 14
15 Longitudinal Impedance Longitudinal Impedance = Fourier transform of the point charge wake Wakepotential of a Gaussian bunch = convolution of point charge wake and charge distribution Fourier transform of the wakepotential of a Gaussian bunch Impedance Fourier transform of the charge distribution Rainer Wanzenberg Impedance & Instabilities June 2017 Page 15
16 Transverse Impedance Transverse Impedance = Fourier transform of the point charge transverse wake Panofsky-Wenzel-Theorem Relation between the transverse and longitudinal Wakepotential Maxwell equation Rainer Wanzenberg Impedance & Instabilities June 2017 Page 16
17 Multipole expansion of the wake Longitudinal Wakepotential Multipole expansion in Cartesian coordinates: Using the Panofsky-Wenzel-Theorem: Transverse dipole wake Rainer Wanzenberg Impedance & Instabilities June 2017 Page 17
18 Wakepotential of a cavity Numerical calculation with the CST Studio suite (commercial 3D code) Rainer Wanzenberg Impedance & Instabilities June 2017 Page 18
19 Numerical calculations There exist several numerical codes to calculate wakefields. Examples are: Non commercial codes (2D, r-z geometry) ABCI, Yong Ho Chin, KEK Echo 2D, Igor Zagorodnov, DESY Recently development: Echo3D (version 1.0) Commercial codes (3D) GdfidL CST (Particle Studio, Microwave Studio) The Maxwell equations are solved on a grid Rainer Wanzenberg Impedance & Instabilities June 2017 Page 19
20 Impedance of a cavity Fourier transform of the time domain calculation Impedance of a cavity modes! The results for the impedance can strongly depend on the mesh and the range of the wakepotential! Rainer Wanzenberg Impedance & Instabilities June 2017 Page 20
21 Rainer Wanzenberg Impedance & Instabilities June 2017 Page 21 ( ) ( ) cos 2 0 t k t V m ω = > i(t) V(t) ( ) = = R LC k C m ω no losses: ( ) ( ) t q t i δ = bunch current: with voltage: with losses: m m m Q k L Q C Q R ω ω ω 2 = = = longitudinal impedance (one mode): ( ) ( ) ( ) = + + = = ω ω ω ω ω ω ω ω ω ω m m m Q i k Q R C i L i I V Z shunt impedance k q E 2 = loss parameter k Equivalent circuit model for the longitudinal wake
22 Frequency domain analysis i(t) V(t) Q -value C = ( 2k ) LC = ω 1 2 m R = ω m Q C 2 GHz frequency loss parameter quality R/Q R ω = 2π m 2 k = V 4 Q Q = 2k ω m f m ( U ) Rainer Wanzenberg Impedance & Instabilities June 2017 Page 22
23 Frequency domain post processing ( ) How to obtain the 2 k = V 4 U loss parameter of a mode 2 E = q k Voltage = integrated electric field with phase factor Point cahrge wake potential of one mode (s > 0) Stored energy Rainer Wanzenberg Impedance & Instabilities June 2017 Page 23
24 Frequency domain post processing: Dipole modes Numerical Solution of the Maxwell Equations Mode frequency Electric and magnetic field Basic post processing Q-value stored energy in the E, B field of the mode voltage with phase factor Loss parameter at beam offset r, R/Q. R For Dipole modes Tesla cavity, 1.62 GHz Dipole mode Rainer Wanzenberg Impedance & Instabilities June 2017 Page 24
25 Wakefield effects and their relation to important beam parameters Beam Parameter: Total bunch charge q 1 Bunch length (and shape) Transverse dimensions (Emittance, Beta-function) Number of bunches Total beam current Kick on the test charge: Synchrotron tune Betatron tune Damping time (Synchrotron Rad.) Chromaticity Ω = ω β + i τ 1 Betatron frequency growth / damping rate Rainer Wanzenberg Impedance & Instabilities June 2017 Page 25
26 Equation of motion (rigid beam approximation) sum: n turns C = Circumference of the storage ring dipole wake ansatz for the solution: Equation of motion is transformed: Impedance is related to betatron frequency shift and instability growth rate Rainer Wanzenberg Impedance & Instabilities June 2017 Page 26
27 Beam-pipe geometry and materials and their impact on impedance Geometric Wake Resistive Wall Wake Loss parameter and Kick parameter Line charge density: Loss parameter of a mode: Kick parameter and dipole wake Rainer Wanzenberg Impedance & Instabilities June 2017 Page 27
28 Example: CMS experimental chamber Transient heating revolution frequency 2.4 V / nc Number of bunches single bunch charge rms bunch length HL-LHC parameters: P ~ 100 W (2800 bunches, 35 nc) CERN-ATS-Note TECH Rainer Wanzenberg Impedance & Instabilities June 2017 Page 28
29 Example: PETRA III Vacuum chamber Resistive wall impedance analytic formula (valid for long bunches) 6 σ = ( Ωm) 6 σ = ( Ωm) 6 σ = ( Ωm) (1 Ω m = 10 6 Ω mm m Cu Al Steel b = pipe radius L = pipe length 2 ) Arc: Al, 80 mm x 40 mm Loss and Kick parameter/length: b = 2 cm Al chamber σ z = 10 mm Loss parameter 1.1 V / (nc m) Rainer Wanzenberg Impedance & Instabilities June 2017 Page 29
30 Example: European XFEL First laser light May 4, 2017 Rainer Wanzenberg Impedance & Instabilities June 2017 Page 30
31 Example: European XFEL 3 rd harmonic RF dogleg 4 accelerator modules 12 accelerator modules main linac collimator Gun laser heater BC0 Before the Undulator: Impedance BC1 bunch compressors BC2 In the Undulator: Impedance SASE1 total energy loss 35.3 MeV total energy spread 15.4 MeV collimators 80% is related to material properties energy spread 14 MeV ( 35 sections) elliptical pipe cavities 274/412 Rainer Wanzenberg Impedance & Instabilities June 2017 Page 31
32 An Introduction to beam instabilities Longitudinal Energy spread TESLA cavity Transverse Head Tail Kick on tail due to the wake of the head Rainer Wanzenberg Impedance & Instabilities June 2017 Page 32
33 Head tail instability Storage ring Circumference C Wakefield: Tail Head Synchrotron oscillations: Positions of Head and Tail are exchanged after one synchrotron oscillation period Equation of motion 0 T s /2 (time for a synchrotron period) N/2 = bunch population of the head Wake potential of the storage ring (also the total kick parameter could be used here) Rainer Wanzenberg Impedance & Instabilities June 2017 Page 33
34 Head Tail Instability (cont.) phasor notation: 0 T s /2 0 T s Stability requires pure imaginary eigen values of the matrix which can be translated into a criteria for: Rainer Wanzenberg Impedance & Instabilities June 2017 Page 34
35 Single bunch instability: TMCI TMCI = Transverse Mode Coupling Instability mode coupling Macro particle model Tail Head Modes of the charge distribution (Vlasov equation with wakefields) Measurement (2009) PETRA III betatron tune synchrotron side band I B T0 Q = β k Q < β 4π E / e β Q s 1 2 Tune shift with intensity Kick parameter Q = 37.13, x Q = 30.31, z Q = 0.049, s f f x x s = 16.9 khz = 39.5 khz f = 6.1 khz Rainer Wanzenberg Impedance & Instabilities June 2017 Page 35
36 Multi bunch instabilities Impedance: HOMs in PETRA Cavities Petra III, h = 3840, rf- buckets N b = 960, 8 ns (125 MHz) N b = 40, 192 ns Multi bunch modes f = 500 MHz, R/Q = 830 Ohm at PETRA III feedback systems are needed often it helps to detune HOMs f = 728 MHz, R/Q = 89 Ohm Rainer Wanzenberg Impedance & Instabilities June 2017 Page 36
37 Ions Equation for an ideal gas: Boltzmann constant Residual gas density at room temperature (300 K) Ion density bunch population Typical cross section for ionization: 2 Mbarn = 2 x cm 2 Rainer Wanzenberg Impedance & Instabilities June 2017 Page 37
38 Example PETRA III: ion density Residual gas density Ion density compare with 20.8 x10 6 electrons /cm average electron density bunch to bunch distance 8 ns oder 2.4 m = 0.24 ions/cm one bunch with 5 x 10 9 electrons (100 ma, 960 Bunche) = 230 ions/cm 960 Bunchen (after one turn) Rainer Wanzenberg Impedance & Instabilities June 2017 Page 38
39 Ion Optics: linear model Drift Quad (beam as a lense) Trapped ions in the beam: + critical ion mass number N b = bunch population σ x, σ y beam dimensions r p = m Ions: A = 2 H 2 A = 16 CH 4 A = 18 H 2 O A = 28 CO, N 2 A = 32 O 2 A = 44 CO 2 Rainer Wanzenberg Impedance & Instabilities June 2017 Page 39
40 Ion effects Effects of trapped ions on the beam: increased emittance, betatron tune shifts, reduced beam lifetime The effect of the ion cloud on the beam can be modelled as a broad band resonator wake field *) (linear approximation of the force) Non linear interaction between beam ion cloud Multi turn effects (trapped ions) Single pass effects (fast ion instability) *) L. Wang et al. Phys. Rev. STAB 14, (2011) Suppression of beam-ion instability in electron rings with multibunch train beam fillings Rainer Wanzenberg Impedance & Instabilities June 2017 Page 40
41 Example Ion effects at PETRA III PETRA III vertical emittance increase (data from June 2015) larger vert. emittance (~ factor 2) strange tune spectrum + additional lines in the multibunch spectrum 2014: Installation of new vacuum chambers The effects disappeared with improved vacuum conditions (conditioning) Rainer Wanzenberg Impedance & Instabilities June 2017 Page 41
42 Conclusion: Less is More less ions less impedance more beam current more luminosity more brilliance vacuum chamber design small loss and kick parameters I B T0 Q = β k < β 4π E / e Q s 1 2 Rainer Wanzenberg Impedance & Instabilities June 2017 Page 42
43 Thank you for your attention! Rainer Wanzenberg Impedance & Instabilities June 2017 Page 43
Wakefields and Impedances I. Wakefields and Impedances I
Wakefields and Impedances I Wakefields and Impedances I An Introduction R. Wanzenberg M. Dohlus CAS Nov. 2, 2015 R. Wanzenberg Wakefields and Impedances I CAS, Nov. 2015 Page 1 Introduction Wake Field
More informationEmittance Growth and Tune Spectra at PETRA III
Emittance Growth and Tune Spectra at PETRA III Presentation at the ECLOUD 2010 workshop Rainer Wanzenberg ECLOUD 2010 October 8-12, 2010 Statler Hotel, Cornell University Ithaca, New York USA PETRA III
More informationCalculation of Wakefields and Higher Order Modes for the New Design of the Vacuum Chamber of the ALICE Experiment for the HL-LHC
CERN-ACC-NOTE-2017-0033 23rd May 2017 rainer.wanzenberg@desy.de Calculation of Wakefields and Higher Order Modes for the New Design of the Vacuum Chamber of the ALICE Experiment for the HL-LHC R. Wanzenberg
More informationTapered Transitions Dominating the PETRA III Impedance Model.
Tapered Transitions Dominating the PETRA III Impedance Model. ICFA Mini-Workshop: Electromagnetic Wake Fields and Impedances in Particle Accelerators Rainer Wanzenberg DESY April 26, 2014 Outline > PETRA
More informationIndex. Accelerator model 8 Adiabatic damping 32, 141 Air-bag model 338 Alternating explicit time scheme 112 Azimuthal modes, see Modes
Index Accelerator model 8 Adiabatic damping 32, 141 Air-bag model 338 Alternating explicit time scheme 112 Azimuthal modes, see Modes Beam breakup in linacs dipole mode 136 higher modes 160 quadrupole
More informationCERN Accelerator School Wakefields. Prof. Dr. Ursula van Rienen, Franziska Reimann University of Rostock
CERN Accelerator School Wakefields Prof. Dr. Ursula van Rienen, Franziska Reimann University of Rostock Contents The Term Wakefield and Some First Examples Basic Concept of Wakefields Basic Definitions
More informationThe TESLA Dogbone Damping Ring
The TESLA Dogbone Damping Ring Winfried Decking for the TESLA Collaboration April 6 th 2004 Outline The Dogbone Issues: Kicker Design Dynamic Aperture Emittance Dilution due to Stray-Fields Collective
More informationInstabilities Part III: Transverse wake fields impact on beam dynamics
Instabilities Part III: Transverse wake fields impact on beam dynamics Giovanni Rumolo and Kevin Li 08/09/2017 Beam Instabilities III - Giovanni Rumolo and Kevin Li 2 Outline We will close in into the
More informationLongitudinal Impedance Budget and Simulations for XFEL. Igor Zagorodnov DESY
Longitudinal Impedance Budget and Simulations for XFEL Igor Zagorodnov 14.3.211 DESY Beam dynamics simulations for the European XFEL Full 3D simulation method (2 CPU, ~1 hours) Gun LH M 1,1 M 1,3 E1 13
More informationEvaluation of In-Vacuum Wiggler Wakefield Impedances for SOLEIL and MAX IV
26/11/2014 European Synchrotron Light Source Workshop XXII 1 Evaluation of In-Vacuum Wiggler Wakefield Impedances for SOLEIL and MAX IV F. Cullinan, R. Nagaoka (SOLEIL, St. Aubin, France) D. Olsson, G.
More informationFirst Collective Effects Measurements in NSLS-II A. Blednykh Accelerator Physicist, BNL/NSLS-II Sep , 2014
First Collective Effects Measurements in NSLS-II A. Blednykh Accelerator Physicist, BNL/NSLS-II Sep. 17-19, 2014 (LOWεRING 2014) 1 BROOKHAVEN SCIENCE ASSOCIATES Outline Phase 1 (25mA / PETRA-III) and Phase
More informationBeam Physics at SLAC. Yunhai Cai Beam Physics Department Head. July 8, 2008 SLAC Annual Program Review Page 1
Beam Physics at SLAC Yunhai Cai Beam Physics Department Head July 8, 2008 SLAC Annual Program Review Page 1 Members in the ABP Department * Head: Yunhai Cai * Staff: Gennady Stupakov Karl Bane Zhirong
More informationBeam Dynamics and SASE Simulations for XFEL. Igor Zagorodnov DESY
Beam Dynamics and SASE Simulations for XFEL Igor Zagorodnov 4.. DESY Beam dynamics simulations for the European XFEL Full 3D simulation method ( CPU, ~ hours) Gun LH M, M,3 E = 3 MeV E = 7 MeV E 3 = 4
More informationSingle-Bunch Effects from SPX Deflecting Cavities
Single-Bunch Effects from SPX Deflecting Cavities Yong-Chul Chae and Louis Emery Accelerator Operation Group Accelerator System Division Measurements March 13, 2013 Introduction The single bunch current
More informationCSR calculation by paraxial approximation
CSR calculation by paraxial approximation Tomonori Agoh (KEK) Seminar at Stanford Linear Accelerator Center, March 3, 2006 Short Bunch Introduction Colliders for high luminosity ERL for short duration
More informationFrequency and time domain analysis of trapped modes in the CERN Proton Synchrotron
Frequency and time domain analysis of trapped modes in the CERN Proton Synchrotron Serena Persichelli CERN Impedance and collective effects BE-ABP-ICE Abstract The term trapped mode refers to a resonance
More informationModeling of Space Charge Effects and Coherent Synchrotron Radiation in Bunch Compression Systems. Martin Dohlus DESY, Hamburg
Modeling of Space Charge Effects and Coherent Synchrotron Radiation in Bunch Compression Systems Martin Dohlus DESY, Hamburg SC and CSR effects are crucial for design & simulation of BC systems CSR and
More informationThomX Machine Advisory Committee. (LAL Orsay, March ) Ring Beam Dynamics
ThomX Machine Advisory Committee (LAL Orsay, March 20-21 2017) Ring Beam Dynamics A. Loulergue, M. Biagini, C. Bruni, I. Chaikovska I. Debrot, N. Delerue, A. Gamelin, H. Guler, J. Zang Programme Investissements
More informationFast Simulation of FEL Linacs with Collective Effects. M. Dohlus FLS 2018
Fast Simulation of FEL Linacs with Collective Effects M. Dohlus FLS 2018 A typical X-FEL gun environment photo cathode cavity, solenoid, drift straight cavity, quadrupole, drift dispersive bend, quadrupole,
More informationStudies of trapped modes in the new extraction septum of the CERN Proton Synchrotron
Studies of trapped modes in the new extraction septum of the CERN Proton Synchrotron Serena Persichelli CERN Impedance and collective effects (BE-ABP-ICE) LIU LHC Injectors Upgrade project Università di
More informationElectron Cloud in Wigglers
Electron Cloud in Wigglers considering DAFNE, ILC, and CLIC Frank Zimmermann, Giulia Bellodi, Elena Benedetto, Hans Braun, Roberto Cimino, Maxim Korostelev, Kazuhito Ohmi, Mauro Pivi, Daniel Schulte, Cristina
More informationFuture Light Sources March 5-9, 2012 Low- alpha mode at SOLEIL 1
Introduction: bunch length measurements Reminder of optics Non- linear dynamics Low- alpha operation On the user side: THz and X- ray short bunch science CSR measurement and modeling Future Light Sources
More informationTransverse dynamics Selected topics. Erik Adli, University of Oslo, August 2016, v2.21
Transverse dynamics Selected topics Erik Adli, University of Oslo, August 2016, Erik.Adli@fys.uio.no, v2.21 Dispersion So far, we have studied particles with reference momentum p = p 0. A dipole field
More informationPAL LINAC UPGRADE FOR A 1-3 Å XFEL
PAL LINAC UPGRADE FOR A 1-3 Å XFEL J. S. Oh, W. Namkung, Pohang Accelerator Laboratory, POSTECH, Pohang 790-784, Korea Y. Kim, Deutsches Elektronen-Synchrotron DESY, D-603 Hamburg, Germany Abstract With
More informationarxiv: v1 [physics.acc-ph] 21 Oct 2014
SIX-DIMENSIONAL WEAK STRONG SIMULATIONS OF HEAD-ON BEAM BEAM COMPENSATION IN RHIC arxiv:.8v [physics.acc-ph] Oct Abstract Y. Luo, W. Fischer, N.P. Abreu, X. Gu, A. Pikin, G. Robert-Demolaize BNL, Upton,
More informationAccelerator Physics. Tip World Scientific NEW JERSEY LONDON SINGAPORE BEIJING SHANGHAI HONG KONG TAIPEI BANGALORE. Second Edition. S. Y.
Accelerator Physics Second Edition S. Y. Lee Department of Physics, Indiana University Tip World Scientific NEW JERSEY LONDON SINGAPORE BEIJING SHANGHAI HONG KONG TAIPEI BANGALORE Contents Preface Preface
More informationmodeling of space charge effects and CSR in bunch compression systems
modeling of space charge effects and CSR in bunch compression systems SC and CSR effects are crucial for the simulation of BC systems CSR and related effects are challenging for EM field calculation non-csr
More informationSuperconducting RF Accelerators: Why all the interest?
Superconducting RF Accelerators: Why all the interest? William A. Barletta Director, United States Particle Accelerator School Dept. of Physics, MIT The HEP prespective ILC PROJECT X Why do we need RF
More informationLOLA: Past, present and future operation
LOLA: Past, present and future operation FLASH Seminar 1/2/29 Christopher Gerth, DESY 8/5/29 FLASH Seminar Christopher Gerth 1 Outline Past Present Future 8/5/29 FLASH Seminar Christopher Gerth 2 Past
More informationParameter selection and longitudinal phase space simulation for a single stage X-band FEL driver at 250 MeV
Parameter selection and longitudinal phase space simulation for a single stage X-band FEL driver at 25 MeV Yipeng Sun and Tor Raubenheimer, Juhao Wu SLAC, Stanford, CA 9425, USA Hard x-ray Free electron
More informationLattice Design for the Taiwan Photon Source (TPS) at NSRRC
Lattice Design for the Taiwan Photon Source (TPS) at NSRRC Chin-Cheng Kuo On behalf of the TPS Lattice Design Team Ambient Ground Motion and Civil Engineering for Low Emittance Electron Storage Ring Workshop
More informationAccelerator Physics. Accelerator Development
Accelerator Physics The Taiwan Light Source (TLS) is the first large accelerator project in Taiwan. The goal was to build a high performance accelerator which provides a powerful and versatile light source
More informationCEPC and FCCee parameters from the viewpoint of the beam-beam and electron cloud effects. K. Ohmi (KEK) IAS-HEP, HKUST, Hong Kong Jan.
CEPC and FCCee parameters from the viewpoint of the beam-beam and electron cloud effects K. Ohmi (KEK) IAS-HEP, HKUST, Hong Kong Jan. 22-25, 2018 CEPC Parameters Y. Zhang, CEPC conference Nov. 2017, IHEP
More informationStatus of linear collider designs:
Status of linear collider designs: Main linacs Design overview, principal open issues G. Dugan March 11, 2002 Linear colliders: main linacs The main linac is the heart of the linear collider TESLA, NLC/JLC,
More informationLattice Design and Performance for PEP-X Light Source
Lattice Design and Performance for PEP-X Light Source Yuri Nosochkov SLAC National Accelerator Laboratory With contributions by M-H. Wang, Y. Cai, X. Huang, K. Bane 48th ICFA Advanced Beam Dynamics Workshop
More informationLinear Collider Collaboration Tech Notes
LCC 0035 07/01/00 Linear Collider Collaboration Tech Notes More Options for the NLC Bunch Compressors January 7, 2000 Paul Emma Stanford Linear Accelerator Center Stanford, CA Abstract: The present bunch
More informationWakefield Effects of Collimators in LCLS-II
Wakefield Effects of Collimators in LCLS-II LCLS-II TN-15-38 10/7/2015 K. Bane SLAC, Menlo Park, CA 94025, USA October 7, 2015 LCLSII-TN-15-38 L C L S - I I T E C H N I C A L N O T E LCLS-TN-15-38 October
More informationFirst propositions of a lattice for the future upgrade of SOLEIL. A. Nadji On behalf of the Accelerators and Engineering Division
First propositions of a lattice for the future upgrade of SOLEIL A. Nadji On behalf of the Accelerators and Engineering Division 1 SOLEIL : A 3 rd generation synchrotron light source 29 beamlines operational
More informationFURTHER UNDERSTANDING THE LCLS INJECTOR EMITTANCE*
Proceedings of FEL014, Basel, Switzerland FURTHER UNDERSTANDING THE LCLS INJECTOR EMITTANCE* F. Zhou, K. Bane, Y. Ding, Z. Huang, and H. Loos, SLAC, Menlo Park, CA 9405, USA Abstract Coherent optical transition
More informationNumerical study of FII in the ILC Damping Ring
Numerical study of FII in the ILC Damping Ring L. Wang, Y. Cai and T. Raubenheimer SLAC LCDR07 - Damping Rings R&D Meeting March 5-7, 2007 INFN-LNF, Frascati Outline Introduction Simulation Wake of ion
More informationEmittance preservation in TESLA
Emittance preservation in TESLA R.Brinkmann Deutsches Elektronen-Synchrotron DESY,Hamburg, Germany V.Tsakanov Yerevan Physics Institute/CANDLE, Yerevan, Armenia The main approaches to the emittance preservation
More informationImpedance and Collective Effects in Future Light Sources. Karl Bane FLS2010 Workshop 1 March 2010
Impedance and Collective Effects in Future Light Sources Karl Bane FLS2010 Workshop 1 March 2010 In future ring-based light sources, the combination of low emittance and high current will mean that collective
More informationElectron cloud effects in KEKB and ILC
Electron cloud effects in KEKB and ILC K. OhmiKEK Joint DESY and University of Hamburg Accelerator Physics Seminar 21, August, 2007, DESY Thanks for the hospitality and GuoXing, Rainer and Eckhard. Contents
More informationX-band RF driven hard X-ray FELs. Yipeng Sun ICFA Workshop on Future Light Sources March 5-9, 2012
X-band RF driven hard X-ray FELs Yipeng Sun ICFA Workshop on Future Light Sources March 5-9, 2012 Motivations & Contents Motivations Develop more compact (hopefully cheaper) FEL drivers, L S C X-band (successful
More informationElectron Cloud Simulations: Beam Instabilities and Wake Fields
Electron Cloud Simulations: Beam Instabilities and Wake Fields G. Rumolo and F. Zimmermann SL/AP, CERN, Geneva, Switzerland Abstract HEADTAIL is a simulation programme developed at CERN which is aimed
More informationWakefields in the LCLS Undulator Transitions. Abstract
SLAC-PUB-11388 LCLS-TN-05-24 August 2005 Wakefields in the LCLS Undulator Transitions Karl L.F. Bane Stanford Linear Accelerator Center SLAC, Stanford, CA 94309, USA Igor A. Zagorodnov Deutsches Electronen-Synchrotron
More informationIII. CesrTA Configuration and Optics for Ultra-Low Emittance David Rice Cornell Laboratory for Accelerator-Based Sciences and Education
III. CesrTA Configuration and Optics for Ultra-Low Emittance David Rice Cornell Laboratory for Accelerator-Based Sciences and Education Introduction Outline CESR Overview CESR Layout Injector Wigglers
More informationBeam instabilities (I)
Beam instabilities (I) Giovanni Rumolo in CERN Accelerator School, Advanced Level, Trondheim Wednesday 21.08.2013 Big thanks to H. Bartosik, G. Iadarola, K. Li, N. Mounet, B. Salvant, R. Tomás, C. Zannini
More informationElectron cloud simulations: beam instabilities and wakefields
PHYSICAL REVIEW SPECIAL TOPICS - ACCELERATORS AND BEAMS, VOLUME, 11 () Electron cloud simulations: beam instabilities and wakefields G. Rumolo and F. Zimmermann CERN, CH 111 Geneva 3, Switzerland (Received
More informationBeam Dynamics. Gennady Stupakov. DOE High Energy Physics Review June 2-4, 2004
Beam Dynamics Gennady Stupakov DOE High Energy Physics Review June 2-4, 2004 Beam Dynamics Research in ARDA Broad expertise in many areas: lattice design, collective effects, electron cloud, beam-beam
More informationIntroduction to Collider Physics
Introduction to Collider Physics William Barletta United States Particle Accelerator School Dept. of Physics, MIT The Very Big Picture Accelerators Figure of Merit 1: Accelerator energy ==> energy frontier
More informationEstimates of local heating due to trapped modes in vacuum chamber
Estimates of local heating due to trapped modes in vacuum chamber Gennady Stupakov SLAC National Accelerator Laboratory, Menlo Park, CA 94025 CERN, April 29, 2016 2 Motivation The motivation for this analysis
More informationLCLS-II SCRF start-to-end simulations and global optimization as of September Abstract
SLAC National Accelerator Lab LCLS-II TN-17-4 February 217 LCLS-II SCRF start-to-end simulations and global optimization as of September 216 G. Marcus SLAC, Menlo Park, CA 9425 J. Qiang LBNL, Berkeley,
More informationLinac Driven Free Electron Lasers (III)
Linac Driven Free Electron Lasers (III) Massimo.Ferrario@lnf.infn.it SASE FEL Electron Beam Requirements: High Brightness B n ( ) 1+ K 2 2 " MIN r #$ % &B! B n 2 n K 2 minimum radiation wavelength energy
More informationCSR Benchmark Test-Case Results
CSR Benchmark Test-Case Results Paul Emma SLAC January 4, 2 BERLIN CSR Workshop Chicane CSR Test-Case Chicane parameters symbol value unit Bend magnet length (not curved length) L B.5 m Drift length (projected;
More informationSimulations of single bunch collective effects using HEADTAIL
Simulations of single bunch collective effects using HEADTAIL G. Rumolo, in collaboration with E. Benedetto, O. Boine-Frankenheim, G. Franchetti, E. Métral, F. Zimmermann ICAP, Chamonix, 02.10.2006 Giovanni
More informationTurn-by-Turn Beam Position Measurements at ANKA with LIBERA ELECTRON
Turn-by-Turn Beam Position Measurements at ANKA with LIBERA ELECTRON E.Huttel, I.Birkel, A.S.Müller, P.Wesolowski About ANKA Test by Frequency Generator Experiences in the Booster Experiences in the Storage
More information3. Synchrotrons. Synchrotron Basics
1 3. Synchrotrons Synchrotron Basics What you will learn about 2 Overview of a Synchrotron Source Losing & Replenishing Electrons Storage Ring and Magnetic Lattice Synchrotron Radiation Flux, Brilliance
More informationFACET-II Design, Parameters and Capabilities
FACET-II Design, Parameters and Capabilities 217 FACET-II Science Workshop, October 17-2, 217 Glen White Overview Machine design overview Electron systems Injector, Linac & Bunch compressors, Sector 2
More informationSLS at the Paul Scherrer Institute (PSI), Villigen, Switzerland
SLS at the Paul Scherrer Institute (PSI), Villigen, Switzerland Michael Böge 1 SLS Team at PSI Michael Böge 2 Layout of the SLS Linac, Transferlines Booster Storage Ring (SR) Beamlines and Insertion Devices
More informationBEAM SCREEN ISSUES (with 20 T dipole magnets instead of 8.3 T)
BEAM SCREEN ISSUES (with 20 T dipole magnets instead of 8.3 T) Introduction and current LHC beam screen Magneto-Resistance (MR) What was done in the past (approx. of the approx. Kohler s rule) Exact and
More informationEvaluating the Emittance Increase Due to the RF Coupler Fields
Evaluating the Emittance Increase Due to the RF Coupler Fields David H. Dowell May 2014 Revised June 2014 Final Revision November 11, 2014 Abstract This technical note proposes a method for evaluating
More informationLongitudinal Dynamics
Longitudinal Dynamics F = e (E + v x B) CAS Bruges 16-25 June 2009 Beam Dynamics D. Brandt 1 Acceleration The accelerator has to provide kinetic energy to the charged particles, i.e. increase the momentum
More informationPBL (Problem-Based Learning) scenario for Accelerator Physics Mats Lindroos and E. Métral (CERN, Switzerland) Lund University, Sweden, March 19-23,
PBL (Problem-Based Learning) scenario for Accelerator Physics Mats Lindroos and E. Métral (CERN, Switzerland) Lund University, Sweden, March 19-23, 2007 As each working day, since the beginning of the
More informationLow energy electron storage ring with tunable compaction factor
REVIEW OF SCIENTIFIC INSTRUMENTS 78, 075107 2007 Low energy electron storage ring with tunable compaction factor S. Y. Lee, J. Kolski, Z. Liu, X. Pang, C. Park, W. Tam, and F. Wang Department of Physics,
More information!"#$%$!&'()$"('*+,-')'+-$#..+/+,0)&,$%.1&&/$ LONGITUDINAL BEAM DYNAMICS
LONGITUDINAL BEAM DYNAMICS Elias Métral BE Department CERN The present transparencies are inherited from Frank Tecker (CERN-BE), who gave this course last year and who inherited them from Roberto Corsini
More informationUltra-Short Low Charge Operation at FLASH and the European XFEL
Ultra-Short Low Charge Operation at FLASH and the uropean XFL Igor Zagorodnov DSY, Hamburg, Germany 5.8. The 3nd FL Conference, Malmö Outline FLASH layout and desired beam parameters Technical constraints
More informationThe CERN Accelerator School holds courses in all of the member states of CERN. 2013, Erice, Italy
The CERN Accelerator School holds courses in all of the member states of CERN 2013, Erice, Italy Superconductivity for Accelerators Numerous changes in last weeks Background RF Magnets Technology Case
More informationCommissioning of PETRA III. Klaus Balewski on behalf of the PETRA III Team IPAC 2010, 25 May, 2010
Commissioning of PETRA III Klaus Balewski on behalf of the PETRA III Team IPAC 2010, 25 May, 2010 PETRA III Parameters Circumference (m) Energy (GeV) ε x (nm rad) ε y (pm rad) Current (ma) # bunches Straight
More informationILC Beam Dynamics Studies Using PLACET
ILC Beam Dynamics Studies Using PLACET Andrea Latina (CERN) July 11, 2007 John Adams Institute for Accelerator Science - Oxford (UK) Introduction Simulations Results Conclusions and Outlook PLACET Physical
More informationElectron-Cloud Theory & Simulations
(1) e cloud build up Electron-Cloud Theory & Simulations Frank Zimmermann,, SL/AP distribution, line & volume density, dose ( scrubbing), energy spectrum, LHC heat load, various fields (dipole, solenoids,
More informationINSTABILITIES IN LINACS. Massimo Ferrario INFN-LNF
INSTABILITIES IN LINACS Massimo Ferrario INFN-LNF Trondheim, 4 August, 13 SELF FIELDS AND WAKE FIELDS Direct self fields Image self fields Space Charge Wake fields γ = 1 1 β E = q 4πε o ( 1 β ) ( 1 β sin
More informationA Bunch Compressor for the CLIC Main Beam
A Bunch Compressor for the CLIC Main Beam F.Stulle, A. Adelmann, M. Pedrozzi March 14, 2007 Abstract The last bunch compressor chicane in front of the main linac of the multi TeV linear collider CLIC is
More informationA 6 GeV Compact X-ray FEL (CXFEL) Driven by an X-Band Linac
A 6 GeV Compact X-ray FEL (CXFEL) Driven by an X-Band Linac Zhirong Huang, Faya Wang, Karl Bane and Chris Adolphsen SLAC Compact X-Ray (1.5 Å) FEL Parameter symbol LCLS CXFEL unit Bunch Charge Q 250 250
More informationOn the future plan of KEK for ILC(International Linear Collider) Junji Urakawa(KEK) Contents
On the future plan of KEK for ILC(International Linear Collider) Junji Urakawa(KEK) 2004.10.24 Contents 0. Outline until now. Review of SC-LC(TESLA) and R&D items. R&D Items at ATF. R&D plans for Superconducting
More informationReview of proposals of ERL injector cryomodules. S. Belomestnykh
Review of proposals of ERL injector cryomodules S. Belomestnykh ERL 2005 JLab, March 22, 2005 Introduction In this presentation we will review injector cryomodule designs either already existing or under
More informationCavity Field Maps (TESLA & 3 rd Harmonic Cavity) Undulator Wakes. Estimation of CSR Effects for FLASH2HGHG
Cavity Field Maps (TESLA & 3 rd Harmonic Cavity) Undulator Wakes Estimation of CSR Effects for FLASHHGHG Cavity Field Maps (TESLA & 3 rd Harmonic Cavity) 3D field map files for ASTRA in E3D format files
More informationOverview of LHC Accelerator
Overview of LHC Accelerator Mike Syphers UT-Austin 1/31/2007 Large Hadron Collider ( LHC ) Outline of Presentation Brief history... Luminosity Magnets Accelerator Layout Major Accelerator Issues U.S. Participation
More informationAccelerator R&D Opportunities: Sources and Linac. Developing expertise. D. Rubin, Cornell University
Accelerator R&D Opportunities: Sources and Linac D. Rubin, Cornell University Electron and positron sources Requirements Status of R&D Linac Modeling of beam dynamics Development of diagnostic and tuning
More informationELIC Design. Center for Advanced Studies of Accelerators. Jefferson Lab. Second Electron-Ion Collider Workshop Jefferson Lab March 15-17, 2004
ELIC Design Ya. Derbenev, K. Beard, S. Chattopadhyay, J. Delayen, J. Grames, A. Hutton, G. Krafft, R. Li, L. Merminga, M. Poelker, E. Pozdeyev, B. Yunn, Y. Zhang Center for Advanced Studies of Accelerators
More informationTransverse beam stability and Landau damping in hadron colliders
Work supported by the Swiss State Secretariat for Educa6on, Research and Innova6on SERI Transverse beam stability and Landau damping in hadron colliders C. Tambasco J. Barranco, X. Buffat, T. Pieloni Acknowledgements:
More informationStatus of Fast Ion Instability Studies
Zur Anzeige wird der QuickTime Dekompressor TIFF (Unkomprimiert) benötigt. Status of Fast Ion Instability Studies Guoxing Xia presented by E. Elsen European LC Workshop, Jan 8-9, 2007, Daresbury 0 Ion
More informationPart V Undulators for Free Electron Lasers
Part V Undulators for Free Electron Lasers Pascal ELLEAUME European Synchrotron Radiation Facility, Grenoble V, 1/22, P. Elleaume, CAS, Brunnen July 2-9, 2003. Oscillator-type Free Electron Laser V, 2/22,
More informationCompressor Ring. Contents Where do we go? Beam physics limitations Possible Compressor ring choices Conclusions. Valeri Lebedev.
Compressor Ring Valeri Lebedev Fermilab Contents Where do we go? Beam physics limitations Possible Compressor ring choices Conclusions Muon Collider Workshop Newport News, VA Dec. 8-1, 8 Where do we go?
More information6 Bunch Compressor and Transfer to Main Linac
II-159 6 Bunch Compressor and Transfer to Main Linac 6.1 Introduction The equilibrium bunch length in the damping ring (DR) is 6 mm, too long by an order of magnitude for optimum collider performance (σ
More informationLongitudinal Top-up Injection for Small Aperture Storage Rings
Longitudinal Top-up Injection for Small Aperture Storage Rings M. Aiba, M. Böge, Á. Saá Hernández, F. Marcellini and A. Streun Paul Scherrer Institut Introduction Lower and lower horizontal emittances
More informationWG2 on ERL light sources CHESS & LEPP
Charge: WG2 on ERL light sources Address and try to answer a list of critical questions for ERL light sources. Session leaders can approach each question by means of (a) (Very) short presentations (b)
More informatione + e - Linear Collider
e + e - Linear Collider Disclaimer This talk was lifted from an earlier version of a lecture by N.Walker Eckhard Elsen DESY DESY Summer Student Lecture 3 rd August 2006 1 Disclaimer II Talk is largely
More informationDiagnostic Systems for Characterizing Electron Sources at the Photo Injector Test Facility at DESY, Zeuthen site
1 Diagnostic Systems for Characterizing Electron Sources at the Photo Injector Test Facility at DESY, Zeuthen site Sakhorn Rimjaem (on behalf of the PITZ team) Motivation Photo Injector Test Facility at
More informationAccelerator. Physics of PEP-I1. Lecture #7. March 13,1998. Dr. John Seeman
Accelerator Physics of PEP-1 Lecture #7 March 13,1998 Dr. John Seeman Accelerator Physics of PEPJ John Seeman March 13,1998 1) What is PEP-? Lecture 1 2) 3) Beam parameters for an luminosity of 3~1~~/cm~/sec
More informationAccelerator Physics Issues of ERL Prototype
Accelerator Physics Issues of ERL Prototype Ivan Bazarov, Geoffrey Krafft Cornell University TJNAF ERL site visit (Mar 7-8, ) Part I (Bazarov). Optics. Space Charge Emittance Compensation in the Injector
More informationBeam Breakup, Feynman and Complex Zeros
Beam Breakup, Feynman and Complex Zeros Ivan Bazarov brown bag seminar, 16 Jan 04 Ivan Bazarov, BBU, feynman and complex zeros, Brown Bag seminar, 16 January 2004 1 Outline BBU: code-writing and simulation
More informationImpedance Minimization by Nonlinear Tapering
Impedance Minimization by Nonlinear Tapering Boris Podobedov Brookhaven National Lab Igor Zagorodnov DESY PAC-7, Albuquerque, NM June 7, 7 BROOKHAVEN SCIENCE ASSOCIATES Outline Motivation Review of theoretical
More informationCompressor Lattice Design for SPL Beam
EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH CERN A&B DIVISION AB-Note-27-34 BI CERN-NUFACT-Note-153 Compressor Lattice Design for SPL Beam M. Aiba Abstract A compressor ring providing very short proton
More informationElectron Cloud Studies for KEKB and ATF KEK, May 17 May 30, 2003
Electron Cloud Studies for KEKB and ATF KEK, May 17 May 3, 23 F. Zimmermann April 12, 23 Abstract I describe a few recent electron-cloud simulations for KEKB and the ATF. For KEKB the dependence of the
More informationPhysics 610. Adv Particle Physics. April 7, 2014
Physics 610 Adv Particle Physics April 7, 2014 Accelerators History Two Principles Electrostatic Cockcroft-Walton Van de Graaff and tandem Van de Graaff Transformers Cyclotron Betatron Linear Induction
More informationANALYSIS OF HIGH ORDER MODES IN 1.3 GHZ CW SRF ELECTRON LINAC FOR A LIGHT SOURCE
ANALYSIS OF HIGH ORDER MODES IN 1.3 GHZ CW SRF ELECTRON LINAC FOR A LIGHT SOURCE A. Sukhanov, A. Vostrikov, V. Yakovlev, Fermilab, Batavia, IL 60510, USA Abstract Design of a Light Source (LS) based on
More informationLinac optimisation for the New Light Source
Linac optimisation for the New Light Source NLS source requirements Electron beam requirements for seeded cascade harmonic generation LINAC optimisation (2BC vs 3 BC) CSR issues energy chirp issues jitter
More informationConceptual design of an accumulator ring for the Diamond II upgrade
Journal of Physics: Conference Series PAPER OPEN ACCESS Conceptual design of an accumulator ring for the Diamond II upgrade To cite this article: I P S Martin and R Bartolini 218 J. Phys.: Conf. Ser. 167
More informationTime resolved transverse and longitudinal phase space measurements at the high brightness photo injector PITZ
Time resolved transverse and longitudinal phase space measurements at the high brightness photo injector PITZ 1. Motivation 2. Transverse deflecting structure 3. Longitudinal phase space tomography 4.
More information