Keyword: wakefield
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MOPRO033 Design and Feasibility Study of a Transverse Halo Collimation System for ATF2 collimation, simulation, background, betatron 145
 
  • N. Fuster-Martínez
    Valencia University, Atomic Molecular and Nuclear Physics Department, Valencia, Spain
  • P. Bambade, S. Liu, S. Wallon
    LAL, Orsay, France
  • A. Faus-Golfe, J. Resta-López
    IFIC, Valencia, Spain
  • K. Kubo, T. Okugi, T. Tauchi, N. Terunuma
    KEK, Ibaraki, Japan
  • I. Podadera, F. Toral
    CIEMAT, Madrid, Spain
  
  Funding: Work supported by FPA2010-21456-C02-01 and by i-link 0704
This paper presents the design of a halo collimation system for the ATF2 beamline. The main objective is the reduction of background noise that limits the performance of key diagnostic devices around the final focal point (IP), especially the Shintake Monitor (IPBSM) used for measuring the nanometer level vertical beam sizes and the future Diamond Sensor (DS) for measuring the beam halo. Beam tracking simulations have been performed to optimize the position and characteristics of the halo collimation devices. Furthermore the collimator wakefield-induced effect is being studied. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO033  
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MOPRO071 Wake Field and Impedance Calculation due to the Beam Position Monitor in the ILSF Storage Ring impedance, vacuum, storage-ring, factory 246
 
  • H. Ghasem
    IPM, Tehran, Iran
  • M. Razazian
    ILSF, Tehran, Iran
  
  The Beam Position Monitors (BPMs) are usually used in the particles accelerators to observe position of the beam and to record longitudinal bunch shape. As the vertical beam size demands beam stabilities on the submicron level in the particle accelerators, there must be a sever precision on designing and fabrication of the BPMs. In this paper, we have explored effect of the BPMs on the total impedance and loss factor of the ILSF storage ring.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO071  
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MOPRO073 Design of Iranian Light Source Facility RF Shielded Bellows impedance, vacuum, storage-ring, electron 252
 
  • H. Ghasem
    IPM, Tehran, Iran
  • J. Etemad Moghadam
    ILSF, Tehran, Iran
  
  Total impedance is one of the most effective parameters for proper operation of an accelerator system. This quantity is evaluated with the summation of individual component impedance of the vacuum pipe and is desired to be as low as possible. The bellows have very significant effects on total impedance of the accelerator systems particularly synchrotron light source storage rings. Design of the bellow for Iranian Light Source Facility (ILSF) with a practical approach for fabrication has been down. Minimization of the total impedance budget, loss factor and the resulting wake field due to the passage of 400 mA electron beam is the main goal of our design.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO073  
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TUOBB01 Accelerator Physics Challenges towards a Plasma Accelerator with Usable Beam Quality plasma, electron, laser, acceleration 961
 
  • R.W. Aßmann, J. Grebenyuk
    DESY, Hamburg, Germany
  
  Enormous progress in compact plasma accelerators has been demonstrated over the recent years in various experiments. These experiments rely on high power, pulsed lasers or short electron bunches to excite ultra-strong wakefields in plasmas. Accelerating gradients have reached several 10 GV/m up to 100 GV/m and the absolute energy gain of electron beams is in the regime of several GeV to 30 GeV. The principle and potential of plasma accelerators has been proven impressively and performance parameters are steadily improving. It is noted that particle accelerators are powerful tools that are ultimately justified by their applications in science, medicine or industry. The demonstration of useable beam quality and a realistic use case remains to be achieved for plasma accelerators. The accelerator physics challenges to arrive at this goal are analyzed and discussed.  
slides icon Slides TUOBB01 [12.407 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUOBB01  
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TUOBB02 Demonstration of Gigavolt-per-meter Accelerating Gradients using Cylindrical Dielectric-lined Waveguides experiment, radiation, electron, laser 965
 
  • B.D. O'Shea, G. Andonian, K.L. Fitzmorris, J. Harrison, J.B. Rosenzweig, O. Williams
    UCLA, Los Angeles, California, USA
  • M.J. Hogan, V. Yakimenko
    SLAC, Menlo Park, California, USA
  
  We present here the results of measurements made showing ~1 GV/m accelerating fields using a hollow dielectric-lined waveguide. The results are comprised of measurement of the energy loss of a high charge (~3 nC) ultrashort (~200 fs), ultra relativistic (20 GeV) beam and concomitant auto-correlation interferometeric techniques to obtain the frequency content of simultaneously generated coherent Cherenkov radiation (CCR). Experiments were conducted at the Facility for Advanced aCcelerator Experimental Tests (FACET) at the SLAC National Laboratory using metal-coated sub-millimeter diameter, ten-centimeter long fused silica tubes. We present simulation and theoretical results in support of the conclusions reached through experiment. These results build on previous work to provide a path towards high gradient accelerating structures for use in compact accelerator schemes, future linear colliders and free-electron lasers.  
slides icon Slides TUOBB02 [2.349 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUOBB02  
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TUPRO064 Scaling Laws of Wake Field Effects for Gradient Changes in the CLIC Main Linac linac, emittance, simulation, damping 1183
 
  • J. Pfingstner, A. Latina, D. Schulte
    CERN, Geneva, Switzerland
  
  The main linac of CLIC is designed to maximize the transportable bunch charge, since this parameter determines the energy efficiency of the CLIC accelerating structures. The bunch charge is limited by short-range wake field effects, which increase the projected beam emittance. For the main linac cost optimisation, it is important to understand how the charge limit scales with the change of the gradient of the accelerating structures. In this paper, we determine such a scaling law via simulations studies. It is shown that from different possible scenarios, the charge limit for a lower gradient CLIC structure scales advantageous and a relatively high charge can be used.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO064  
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TUPRO065 Tests of Beam-based Alignment at FACET linac, emittance, simulation, alignment 1186
 
  • A. Latina, J. Pfingstner, D. Schulte
    CERN, Geneva, Switzerland
  • E. Adli
    University of Oslo, Oslo, Norway
  
  Tests of Beam-Based Alignment have been performed at FACET, with successful results. A flight simulator based on PLACET has been put in place to test the correction algorithms before applying the correction to the real machine. The flight simulator not only helped studying the parameters space in a safe environment, but it also helped developing a graphical interface that the experimenter can use to set each parameter of the correction also during the on-line.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO065  
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TUPME038 Wakefield excitation via a metasurface-loaded waveguide impedance, coupling, simulation, radiation 1437
 
  • E. Sharples
    Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
  • R. Letizia
    Lancaster University, Lancaster, United Kingdom
  
  Funding: Work supported by STFC Quota Studentship grant ST/K520133/1
A metallic waveguide loaded with layers of complementary split ring resonator (CSRR) based metasurface is presented for accelerator and coherent source applications. This structure presents left handed behaviour arising from the strong electrical response of CSRRs which form the metasurface and the transverse field confined between the closely positioned metasurface layers. The loaded waveguide structure is known to have a TM-like mode at 5.47GHz suitable for acceleration. In this paper, the results of wakefield simulations are presented and a narrow band excitation identified around the frequency of the TM-like mode, indicating strong coupling between the beam and the field of this mode. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME038  
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TUPME040 Drive Beam Break-up Control and Practical Gradient Limitation in Collinear Dielectric Wakefield Accelerators acceleration, simulation, linac, quadrupole 1443
 
  • C. Li, W. Gai, J.G. Power, A. Zholents
    ANL, Argonne, Illinois, USA
  • C.-J. Jing
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • C. Li, C.-X. Tang
    TUB, Beijing, People's Republic of China
  
  Dielectric wakefield accelerator (DWA) concept has gained significant attention for the need of the future large scale facilities. For a practical machine, one needs to overcome a major challenge for the DWA that is the efficient energy extraction and stable propagation at the same time for the drive beam. Typically, a slightly off axis beam become unstable in the dielectric channel due to transverse wakefield excitation, that could be controlled if a strong external alternating magnetic focusing channel applied at the same time. However, there is limitation on the practical magnetic field in the focusing channel (typically < 1 Tesla), thus imposing operating point for the DWA. In this article, we explore the operating point of the DWA for various structure frequencies and drive beam charge, particularly on the gradient and total acceleration distance, and provide guidance on the DWA design.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME040  
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TUPME042 Planned High-gradient Flat-beam-driven Dielectric Wakefield Experiments at the Fermilab’s Advanced Superconducting Test Accelerator acceleration, emittance, experiment, controls 1451
 
  • F. Lemery, D. Mihalcea, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  • P. Piot, J. Zhu
    Fermilab, Batavia, Illinois, USA
  • J. Zhu
    CAEP/IFP, Mainyang, Sichuan, People's Republic of China
  
  In beam driven dielectric wakefield acceleration (DWA), high-gradient short-wavelength accelerating fields are generally achieved by employing dielectric-lined waveguides (DLWs)  with small aperture which constraints the beam sizes. In this paper we investigate the possibility of using a low-energy (50-MeV) flat beams to induce high-gradient wakes in a slab-symmetric DLW. We demonstrate via numerical simulations the possibility to produce axial electric field with peak amplitude close to 0.5 GV/m. Our studies are carried out using the Fermilab's Advanced Superconducting Test Accelerator (ASTA) photoinjector beamline. We finally discuss a possible experiment that could be performed in the ASTA photoinjector and eventually at higher energies.    
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME042  
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TUPME043 Temporal Electron-bunch Shaping from a Photoinjector for Advanced Accelerator Applications space-charge, laser, acceleration, gun 1454
 
  • F. Lemery, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  • P. Piot
    Fermilab, Batavia, Illinois, USA
  
  Advanced-accelerator applications often require the production of bunches with shaped temporal distributions. An example of sought-after shape is a linearly-ramped current profile that can be improve the transformer ratio in beam-driven acceleration, or produce energy-modulated pulse for, e.g., the subsequent generation of THz radiation. Typically,  such a shaping is achieved by manipulating ultra-relativistic electron bunches. In this contribution we discuss the possibility of shaping the bunch via photoemission and demonstrate using particle-in-cell simulations the production of MeV electron bunches with quasi-ramped current profile.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME043  
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TUPME048 Injection of a LWFA Electron Bunch in a PWFA Driven by a Self-modulated-proton-bunch plasma, electron, laser, experiment 1470
 
  • P. Muggli
    MPI, Muenchen, Germany
  • L.D. Amorim
    IST, Lisboa, Portugal
  • S. Karsch
    MPQ, Garching, Munich, Germany
  • N.C. Lopes, J. Vieira
    Instituto Superior Tecnico, Lisbon, Portugal
  
  The AWAKE experiment recently approved at CERN will study the acceleration of an externally injected electron bunch in a plasma wakefield accelerator (PWFA) driven by a self-modulated proton bunch. We study the possibility of injecting a bunch created by a laser-driven plasma wakefield accelerator (LWFA). We consider a first plasma source used for self-modulation of the drive bunch and a gas discharge source for acceleration of the collinearly injected bunch. The LWFA produces an electron bunch very short when compared to the PWFA wavelength and with relatively large current, possibly allowing for loading of the wakefields. Short length and high current lead to a small final energy spread. Co-linear injection preserves the incoming bunch quality and insures trapping and acceleration of the whole bunch. The energy of the LWFA electron bunch can easily exceed the trapping energy and can be produced over only a few millimeters gas-jet plasma driven by a laser of relatively modest power by today’s standards. We explore the parameter space suitable for this injection scheme that is more compact, simpler to implement and more suitable for injection in the mm-size accelerator structure.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME048  
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TUPME049 Hosing Suppression in the Self-modulated Wakefield Accelerator plasma, experiment, flattop, controls 1473
 
  • J. Vieira
    IPFN, Lisbon, Portugal
  • W.B. Mori
    UCLA, Los Angeles, California, USA
  • P. Muggli
    MPI, Muenchen, Germany
  
  Funding: FCT-Portugal contract no EXPL/FIS-PLA/0834/1012; European Research Council contract no ERC-2010-AdG Grant 267841; by DOE contract no DE-SC0008491, DE-SC0008316, and DE-FG02- 92-ER40727.
The proton driven plasma wakefield accelerator (PDPWFA) uses short LHC proton (p+) bunches (shorter than the plasma wavelength) as drivers for strongly non-linear plasma waves. Simulations showed that the PDPWFA could be used to accelerate electrons to 600 GeVs in 600 m long plasmas*. Currently available p+ bunches are much longer than the plasma wavelength, being ideal to excite intese wakefields through the self-modulation instability (SMI). An experiment is being prepared at CERN to demonstrate SMI of p+ bunches. In addition, lepton SMI experiments are also being prepared at SLAC, DESY-PITZ and RAL. The hosing instability (HI) is a competing instability that may lead to beam breakup, and needs to be controlled over the long propagation distances required for SMI growth and saturation. In this work we show that the HI can be suppressed after SMI saturation in the linear wakefield excitation regime. SMI saturation before beam-break up can be achieved by seeding SMI, and as long as the initial bunch centroid displacements are within the initial bunch transverse size. The HI suppression occurs via a plasma analogue of the BNS damping in conventional accelerators.
* A. Caldwell et al, Nat. Physics Nat. Phys. 5, 363 (2009). 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME049  
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TUPME050 Electron Bunch Self-modulation in Long Plasmas at SLAC FACET plasma, experiment, electron, radiation 1476
 
  • P. Muggli
    MPI, Muenchen, Germany
  • E. Adli, V.K.B. Olsen
    University of Oslo, Oslo, Norway
  • L.D. Amorim
    IST, Lisboa, Portugal
  • S.J. Gessner, M.J. Hogan, S.Z. Li, M.D. Litos
    SLAC, Menlo Park, California, USA
  • C. Joshi, K.A. Marsh, W.B. Mori, N. Vafaei-Najafabadi
    UCLA, Los Angeles, California, USA
  • N.C. Lopes, J. Vieira
    Instituto Superior Tecnico, Lisbon, Portugal
  • O. Reimann
    MPI-P, München, Germany
  
  Funding: This work performed in part under DOE Contract DE-AC02-76SF00515.
We study the physics of self-modulation instability (SMI) of long, when compared to the wake wavelength, electron and positron bunches in pre-formed plasmas at SLAC-FACET. Self-modulation is the result of the action of focusing/defocusing transverse wakefields on the bunch radius. Self-modulation leads to observables such as overall defocusing of the bunch, periodic modulation of the bunch radius at the wake period and multi-GeV energy gain/loss by drive bunch particles. Defocusing is observed from OTR images, radial self-modulation from CTR spectra and interferometric traces and energy gain/loss from energy spectra with sub-GeV resolution. The plasma density is varied by changing the vapor density ionized by a laser/axicon system. The bunch length, radius and charge can also be varied. The SMI can be seeded using a notch collimator system. Numerical simulations indicate that seeding the SMI mitigates the hose instability. Hose instability can also be seeded, for example by using the RF deflecting cavity to impart a tilt to the incoming bunch axis. The overall experimental plan as well as the latest experimental results obtained with electron bunches will be presented. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME050  
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TUPME051 Self-Injection by Trapping of Plasma Electrons Oscillating in Rising Density Gradient at Vacuum-Plasma Interface plasma, laser, electron, injection 1479
 
  • A. A. Sahai, T.C. Katsouleas
    Duke ECE, Durham, North Carolina, USA
  • P. Muggli
    MPI-P, München, Germany
  
  Funding: DE-SC0010012, NSF-PHY-0936278
We model the trapping of plasma electrons within the density structures excited by a propagating energy source in a rising plasma density gradient. Rising density gradient leads to spatially contiguous coupled up-chirped plasmons (d{ω2pe(x)}/{dx}>0). Therefore phase mixing between plasmons can lead to trapping until the plasmon field is high enough such that e- trajectories returning towards a longer wavelength see a trapping potential. Rising plasma density gradients are ubiquitous for confining the plasma within sources at the vacuum-plasma interfaces. Therefore trapping of plasma-e- in a rising ramp is important for acceleration diagnostics and to understand the energy dissipation from the excited plasmon train [1]. Down-ramp in density [2][3] has been used for plasma-e- trapping within the first bucket behind the driver. Here, in rising density gradient the trapping does not occur in the first plasmon bucket but in subsequent plasmon buckets behind the driver. Trapping reduces the Hamiltonian of each bucket where e- are trapped, so it is a wakefield-decay probe. Preliminary computational results for beam and laser-driven wakefield are shown.
1.Sahai, A. A. et.al.,Proc of IPAC2013, MOPAC10, Oct2013
2.Suk, H. et.al.,Phys. Rev.Lett. 86 2001 10.1103/PhysRevLett.86.1011
3.Dawson, J, Phys Rev 113 1959 10.1103/PhysRev.113.383 		 
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TUPME054 Influence of a Vacuum Gap on a Bunch Wakefield in a Circular Waveguide Filled up with Dielectric vacuum, cavity, radiation, electromagnetic-fields 1489
 
  • T.Yu. Alekhina, A.V. Tyukhtin, V.V. Vorobev
    Saint-Petersburg State University, Saint-Petersburg, Russia
  
  Analysis of electromagnetic field of a particle bunch intersecting several boundaries in a dielectric waveguide is important for the wakefield acceleration technique and other problems of accelerator physics. In previous works we investigated the case of a single boundary in a waveguide*. Now we study the electromagnetic field of the bunch moving in a dielectric circular waveguide and crossing a vacuum cavity. The main attention is given to the case when wakefield (Cherenkov radiation) is generated in dielectric. The behavior of the total field depending on distance and time is explored numerically. Analytical estimations are made as well. Influence of the vacuum gap on the wakefield is considered for different lengths of the gap. It is clarified conditions when the vacuum gap does not practically influence on the wakefield. It is noted that the quasi monochromatic wave (the Cherenkov transition radiation) generated in the vacuum region can be used for restoration of the field in the area after the gap. This effect can be achieved for some optimal parameters of the problem.
* T.Yu. Alekhina, A.V. Tyukhtin, Phys. Rev. ST-AB, v.15, 091302 (2012);
T.Yu. Alekhina, A.V. Tyukhtin, Phys. Rev. ST-AB, v.16, 081301 (2013). 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME054  
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TUPME058 The Argonne Wakefield Accelerator (AWA): Commissioning and Operation gun, electron, laser, experiment 1503
 
  • M.E. Conde, S.P. Antipov, D.S. Doran, W. Gai, C.-J. Jing, C. Li, W. Liu, J.G. Power, J.Q. Qiu, J.H. Shao, C. Whiteford, E.E. Wisniewski
    ANL, Argonne, Illinois, USA
  • S.P. Antipov, C.-J. Jing, J.Q. Qiu
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • S. Cao
    IMP, Lanzhou, People's Republic of China
  • C. Li, J.H. Shao
    TUB, Beijing, People's Republic of China
  • E.E. Wisniewski
    Illinois Institute of Technology, Chicago, Illinois, USA
  
  Funding: Work supported by the U.S. Department of Energy under contract No. DE-AC02-06CH11357.
The commissioning of the upgraded AWA facility is well underway. The new L-band electron gun has been fully commissioned and has been successfully operated with its Cesium Telluride photocathode at a gradient of 80 MV/m. Single bunches of up to 100 nC, and bunch trains of four bunches with up to 80 nC per bunch have been generated. The six new accelerating cavities (L-band, seven cells, pi mode) have been RF conditioned to 12 MW or more; their operation at 10 MW brings the beam energy up to 75 MeV. Measurements of the beam parameters are presently underway, and the use of this intense beam to drive high gradient wakefields will soon follow. One of the main goals of the facility is to generate RF pulses with GW power levels, corresponding to accelerating gradients of hundreds of MV/m and energy gains on the order of 100 MeV per structure. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME058  
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TUPME069 Proton Electron Accelerator at CERN plasma, proton, electron, experiment 1519
 
  • R. Tarkeshian
    MPI, Muenchen, Germany
  
  AWAKE is a proton driven plasma-wakefield acceleration at CERN*, that uses long proton bunches ~ 400 ps from the SPS. In a dense plasma, a long proton bunch is subject toμbunching at plasma period due to the self-modulation instability, SMI**. The self-modulated proton bunch generates large amplitude charge separation through resonant wakefield excitation. Numerical simulations show that when seeded the SMI can grow and saturate over ~4 m in a plasma with density in the (1-10) *1014/cc range. Seeding also allows for deterministic injection of witness bunches in the focusing and accelerating phase of the wakefields. The SPS proton bunch carrying kJ of energy is a unique driver for generation of ~ GeV/m wakefields through 10’s of meters of plasma. The side-injected electrons ~15 MeV can reach GeV energies. The AWAKE experimental layout, the physics of self-modulation, simulation results, plasma source under study, diagnostics plan for bunch modulation measurement using transverse coherent transition radiation***, and phasing of the witness bunch respect to the wave and synchronisation with diagnostics will be presented.****
*A. Caldwel, et. al, Nature Physics 5, 2009
**N. Kumar, A. Pukhov, PRL, 104, 2010
***O. Reimann, R. Tarkeshian, Proc. of IBIC, 2013
**** The work is submitted on behalf of AWAKE collaboration. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME069  
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TUPME073 A Novel Laser Ionized Rb Plasma Source for Plasma Wakefield Accelerators plasma, laser, proton, electron 1522
 
  • E. Öz, F. Batsch, P. Muggli
    MPI-P, München, Germany
  
  Funding: AWAKE collaboration
A proton driven plasma wakefield accelerator* is to be conducted at CERN by the AWAKE collaboration. Externally injected electrons are accelerated in a large gradient (~GeV/m) wakefield. The large gradient is achieved by resonant formation of the wakefield by a train of micro-bunches. Transverse modulation of a long (~12 cm) proton bunch by the self modulation instability** creates these plasma wavelength size (~1 mm) micro-bunches. This resonant mechanism brings a strict requirement on the plasma density uniformity, namely % 0.2, in order for the injected electron bunch to remain in the accelerating and focusing phase of the wakefields. We describe the plasma source*** that satisfies this requirement during the beam plasma interaction. Rb vapor with ~1015 cm-3 density is confined in a 10 m long 4 cm diameter, stainless-steel tube which is heated to ~200 Co by an oil heat exchanger. The access to the source during interaction is provided by custom built fast valves. The vapor is fully tunnel ionized (first e-) by a laser forming a 2 mm diameter plasma channel.
* http://awake.web.cern.ch/awake/
** http://link.aps.org/doi/10.1103/PhysRevLett.104.255003
*** http://dx.doi.org/10.1016/j.nima.2013.10.093
 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME073  
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TUPME075 Simulations on Laser Wakefield Generation in a Parabolic Magnetic-plasma Channel plasma, laser, simulation, electron 1528
 
  • D.N. Gupta, M. Singh
    University of Delhi, Delhi, India
  • D. Jang, H. Suk
    APRI-GIST, Gwangju, Republic of Korea
  • B.S. Sharma
    Kota University, Rajasthan, India
  
  To utilize the laser-plasma channel for laser wakefield acceleration, we have studied the non-paraxial theory of nonlinear propagation of ultra-intense relativistic Gaussian laser pulse in a preformed spatially tapered magneto-plasma channel having a parabolic density profile. A three-dimensional envelope equation for the laser field is derived, which includes the non-paraxial and applied magnetic field effects. An analytical expression for the wakefield is derived and analyzed the results with the help of particle-in-cell (PIC) simulations. It is shown that wakefield structures and the phase of axial component of the wakefield depend on applied external magnetic field. This aspect of theoretical observation can be used in the production of highly collimated mono-energetic x-rays.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME075  
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TUPME076 Numerical modeling of the E-209 self-modulation experiment at SLAC - FACET plasma, electron, simulation, experiment 1531
 
  • L.D. Amorim, L.O. Silva, J. Vieira
    IPFN, Lisbon, Portugal
  • P. Muggli
    MPI, Muenchen, Germany
  
  The E-209 experiment currently running at SLAC- FACET used a long electron bunch (∼ 5 times the plasma wavelength) to drive plasma wakefields through the self- modulation instability. In this work we present and analyze numerical simulation results performed with the particle-in- cell (PIC) code OSIRIS. The results show that SMI saturates after 5cm of propagation in the plasma and that the maxi- mum acceleration wakefields, 15 − 20GV/m, are sustained over a 1m long plasma. Electron bunch energy loss of 4GeV was observed in the simulations.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME076  
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TUPME078 Electron Injection Studies for the AWAKE Experiment at CERN electron, plasma, proton, injection 1537
 
  • A.V. Petrenko, C. Bracco, E. Gschwendtner
    CERN, Geneva, Switzerland
  • K.V. Lotov
    NSU, Novosibirsk, Russia
  • K.V. Lotov
    BINP SB RAS, Novosibirsk, Russia
  • P. Muggli
    MPI, Muenchen, Germany
  
  The AWAKE experiment recently approved at CERN will use the self-modulation instability (SMI) of long (12 cm), relativistic (400 GeV/c) proton bunches in dense plasmas to drive wakefields with accelerating gradients at the GV/m level. These accelerating gradients will be probed by externally injected electrons. In order to preserve the plasma uniformity required for the SMI the first experiments will use on-axis injection of a low energy 10-20 MeV electron beam collinearly with the proton beam. In this article we describe the physics of electron injection into the proton driven SMI wakefields. Requirements on the injected electron beam are determined and the final accelerated beam parameters are obtained via numerical simulations.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME078  
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TUPME079 A Spectrometer for Proton Driven Plasma Wakefield Accelerated Electrons at AWAKE electron, plasma, simulation, proton 1540
 
  • S. Jolly, L.C. Deacon, J.A. Goodhand, S.R. Mandry, M. Wing
    UCL, London, United Kingdom
  • S.R. Mandry
    MPI, Muenchen, Germany
  
  The AWAKE experiment is to be constructed at the CERN Neutrinos to Gran Sasso facility (CNGS). This will be the first experiment to demonstrate electron acceleration by use of a proton driven plasma wakefield. The 400 GeV proton beam from the CERN SPS will excite a wakefield in a plasma cell several metres in length. To observe the plasma wakefield, electrons of a few MeV will be injected into the wakefield following the head of the proton beam. Simulations indicate that electrons will be accelerated to GeV energies by the plasma wakefield. The AWAKE spectrometer is intended to measure both the peak energy and energy spread of these accelerated electrons. The baseline design makes use of a single dipole magnet to separate the electrons from the proton beam. The dispersed electron beam then impacts on a scintillator screen: the resulting scintillation light is collected and recorded by an intensified CCD camera. The design of the spectrometer is detailed with a focus on the scintillator screen. Results of simulations to optimise the scintillator are presented, including studies of the standard GadOx scintillators commonly used for imaging electrons in plasma wakefield experiments.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME079  
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TUPME081 Plasma Wakefield Acceleration at CLARA PARS plasma, simulation, accelerating-gradient, electron 1544
 
  • K. Hanahoe, O. Mete, G.X. Xia
    UMAN, Manchester, United Kingdom
  • D. Angal-Kalinin, J.A. Clarke, J.K. Jones, J.W. McKenzie, B.L. Militsyn, P.H. Williams
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • D. Angal-Kalinin, J.A. Clarke, J.K. Jones, J.W. McKenzie, Y. Wei, C.P. Welsch, P.H. Williams
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • B. Hidding
    USTRAT/SUPA, Glasgow, United Kingdom
  • J.D.A. Smith
    TXUK, Warrington, United Kingdom
  • Y. Wei, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  
  PARS is a proposed Plasma Accelerator Research Station using the planned CLARA (Compact Linear Accelerator for Research and Applications) electron linear accelerator at Daresbury Laboratory in the UK. In this paper, two- dimensional particle-in-cell simulations based on realistic CLARA beam parameters are presented. The results show that an accelerating gradient of 2.0 GV/m can be achieved over an accelerating length of at least 13 cm. Preliminary simulation results for a two bunch scheme show an energy gain of 70% over a length of 13 cm, giving an average accelerating gradient of 1.2 GeV/m.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME081  
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TUPRI019 Incoherent and Coherent Effects of Space Charge Limited Electron Clouds electron, simulation, space-charge, dipole 1594
 
  • F.B. Petrov, O. Boine-Frankenheim, O.S. Haas
    TEMF, TU Darmstadt, Darmstadt, Germany
  
  Funding: Work is supported by the BMBF under contract 05H12RD7.
Recent studies show that the space charge limited (saturated) electron cloud generated by relativistic bunches has strongly inhomogeneous distribution. In particular, a dense electron sheath is formed near the pipe wall. This feature modifies the stopping powers and the microwave transmission compared with the uniform cloud case. In this paper we investigate further the influence of the space charge limited electron cloud on relativistic bunches. In particular, we focus on the incoherent tune spread and compare the results with the homogeneous cloud case. We derive analytical expressions governing the pinch dynamics of the saturated cloud in round geometry. The contribution of the electron cloud sheath to the wake fields is investigated as well. Findings of the analytical theory are then successfully compared with numerical particle-in-cell simulations. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI019  
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TUPRI038 The Low Energy Particle Wakefield Radiation From the Open End of Internally Coated Metallic Tube radiation, experiment, vacuum, resonance 1644
 
  • M. Ivanyan, A. Grigoryan, A. Sargsyan, A.V. Tsakanian
    CANDLE SRI, Yerevan, Armenia
  
  The radiation of the non-relativistic electron beam from the open end of the resistive circular waveguide is presented. The angular and spectral characteristics of the radiation are determined. The possibility of producing the focused guasi-monochromatic radiation is discussed. The principal scheme of the experiments for 5 and 20 MeV AREAL RF photogun linac is presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI038  
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TUPRI042 Numerical Study of the Microbunching Instability at UVSOR-III: Influence of the Resistive and Inductive Impedances electron, impedance, synchrotron, simulation 1656
 
  • E. Roussel, S. Bielawski, C. Evain, C. Szwaj
    PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France
  • M. Adachi, M. Katoh, S.I. Kimura, T. Konomi
    UVSOR, Okazaki, Japan
  • M. Hosaka, Y. Takashima, N. Yamamoto
    Nagoya University, Nagoya, Japan
  • K.S. Ilin, J. Raasch, A. Scheuring, M. Siegel, P. Thoma
    KIT, Karlsruhe, Germany
  • H. Zen
    Kyoto University, Kyoto, Japan
  
  At high charge, relativistic electron bunches circulating in storage rings undergo an instability, the so-called microbunching or the CSR (Coherent Synchrotron Radiation) instability. This instability is due to the interaction of the electrons with their own radiation and leads to the formation of microstructures (at millimeter scale) in the longitudinal phase space. Thanks to a new type of detector, based on superconducting thin film YBCO, it is now possible to observe directly these microstructures and follow their temporal evolution*. These experimental observations open a new way to make severe comparisons with theory. Here we present results of the modeling of the dynamics at UVSOR-III using a one dimensional Vlasov-Fokker-Planck equation. We show that to obtain a relatively good agreement between numerical simulations and experiments, we have to take into account several types of impedance such as the shielded CSR impedance but also the resistive and inductive impedances.
* First Direct, Real Time, Recording of the CSR Pulses Emitted During the Microbunching Instability, using Thin Film YBCO Detectors at UVSOR-III, IPAC2014 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI042  
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TUPRI049 Geometric Beam Coupling Impedance of LHC Secondary Collimators impedance, factory, simulation, HOM 1677
 
  • O. Frasciello, S. Tomassini, M. Zobov
    INFN/LNF, Frascati (Roma), Italy
  • A. Grudiev, N. Mounet, B. Salvant
    CERN, Geneva, Switzerland
  
  Funding: Work supported by European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404
The High Luminosity LHC project is aimed at increasing the LHC luminosity by an order of magnitude. One of the key ingredients to achieve the luminosity goal is the beam intensity increase. In order to keep under control beam instabilities and to avoid excessive power losses a careful design of new vacuum chamber components and an improvement of the present LHC impedance model are required. Collimators are the main impedance contributors. Measurements with beam have revealed that the betatron coherent tune shifts were by about a factor of 2 higher with respect to the theoretical predictions based on the current model. Up to now the resistive wall impedance has been considered as the major impedance contribution for collimators. By carefully simulating their geometric impedance we show that for the graphite collimators with half-gaps higher than 10 mm the geometric impedance exceeds the resistive wall one. In turn, for the tungsten collimators the geometric impedance dominates for all used gap values. Hence, including the geometric collimator impedance into the LHC impedance model enabled us to reach a better agreement between the measured and simulated collimator tune shifts. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI049  
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WEOCA02 Recent Results from CTF3 Two Beam Test Stand HOM, experiment, accelerating-gradient, diagnostics 1880
 
  • W. Farabolini, F. Peauger
    CEA/DSM/IRFU, France
  • Ch. Borgmann, J. Ögren, R.J.M.Y. Ruber
    Uppsala University, Uppsala, Sweden
  • R. Corsini, D. Gamba, A. Grudiev, M.A. Khan, S. Mazzoni, J.L. Navarro Quirante, R. Pan, J.R. Towler, N. Vitoratou, K. Yaqub
    CERN, Geneva, Switzerland
  
  From mid-2012, the Two Beam Test Stand (TBTS) in the CTF3 Experimental Facility is hosting 2 high gradient accelerating structures powered by a single power extraction and transfer structure in a scheme very close to the CLIC basic cell. We report here about the results obtained with this configuration as: energy gain and energy spread in relation with RF phases and power, octupolar transverse beam effects compared with modeling predictions, breakdown rate and breakdown locations within the structures. These structures are the first to be fitted with Wake Field Monitors (WFM) that have been extensively tested and used to further improve the structures alignment on the beam line. These results show the unique capabilities of this test stand to conduct experiments with real beams.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEOCA02  
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WEOBB02 Status of Single-shot EOSD Measurement at ANKA laser, operation, electron, storage-ring 1909
 
  • N. Hiller, A. Borysenko, E. Hertle, V. Judin, B. Kehrer, S. Marsching, A.-S. Müller, M.J. Nasse, M. Schuh, P. Schönfeldt, N.J. Smale, J.L. Steinmann
    KIT, Karlsruhe, Germany
  • P. Peier, B. Steffen
    DESY, Hamburg, Germany
  • V. Schlott
    PSI, Villigen PSI, Switzerland
  
  Funding: This work is funded by the BMBF contract numbers: 05K10VKC, 05K13VKA.
ANKA is the first storage ring in the world with a near-field single-shot electro-optical (EO) bunch profile monitor. The method of electro-optical spectral decoding (EOSD) uses the Pockels effect to modulate the longitudinal electron bunch profile onto a long, chirped laser pulse passing through an EO crystal. The laser pulse is then analyzed with a single-shot spectrometer and from the spectral modulation, the temporal modulation can be extracted. The setup has a sub-ps resolution (granularity) and can measure down to bunch lengths of 1.5 ps RMS for bunch charges as low as 30 pC. With this setup it is possible to study longitudinal beam dynamics (e. g. microbunching) occurring during ANKA's low-alpha-operation, an operation mode with compressed bunches to generate coherent synchrotron radiation in the THz range. In addition to measuring the longitudinal bunch profile, long-ranging wake-fields trailing the electron bunch can also be studied, revealing bunch-bunch interactions. 		 
slides icon Slides WEOBB02 [12.753 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEOBB02  
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WEPRO006 Beam-driven Terahertz Source based on Open Ended Waveguide with a Dielectric Layer radiation, vacuum, optics, experiment 1949
 
  • A.V. Tyukhtin, S.N. Galyamin, V.V. Vorobev
    Saint-Petersburg State University, Saint-Petersburg, Russia
  • S.P. Antipov
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • S. Baturin
    LETI, Saint-Petersburg, Russia
  
  Funding: Work is supported by the Grant of the President of Russian Federation (MK-273.2013.2) and the Russian Foundation for Basic Research (Grant No. 12-02-31258).
Electromagnetic waves with frequencies from 0.1 THz to 10 THz (usually called the Terahertz gap) are of great importance for a number of scientific and practical applications. Different techniques are known allowing generating these frequencies. However, a current trend of physics and industry is to fill this gap with more powerful and efficient sources. For example, recent experiments have shown promising THz generation in dielectric loaded structures*. Developing this area, we consider the THz emitting scheme where an ultrarelativistic charge exits the open end of a cylindrical waveguide with a dielectric layer and produces THz waves in a form of Cherenkov radiation. The end of the waveguide is supposed to be either orthogonal to the structure axis or skewed. To obtain THz frequencies from waveguides with centimeter or millimeter radii, we consider high order modes. We present typical field patterns (in the Fraunhofer zone) and show that the aperture of the vacuum channel gives, as a rule, the main contribution. We also give simple expressions for the angle of the main pattern lobe.
* S. Antipov et al., Appl. Phys. Lett. 100, 132910 (2012). 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO006  
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WEPRO008 A Beam-driven Microwave Undulator for FEL undulator, electron, FEL, linac 1956
 
  • A. Kanareykin, C.-J. Jing, P. Schoessow
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • S. Baturin
    LETI, Saint-Petersburg, Russia
  • A. Zholents
    ANL, Argonne, Ilinois, USA
  
  Funding: DOE SBIR
Microwave waveguides can in principle be used for undulators with periods less than 1 cm. Intensive work has been done on the recently proposed design that operates at the HE11 hybrid mode of a corrugated waveguide; successful experimental results have been reported recently [S.Tantawi Talk at POSIPOL 2012]. In this presentation we propose a beam driven design for an undulator based on an electron bunch train powering a microwave or mm waveguide. The drive bunch train propagates towards the undulating beam inside a dielectric loaded structure or corrugated waveguide generating high power RF. The “smart” waveguide design and a proper bunch spacing of the electron drive beam train provide single mode generation of the high magnitude undulating field that gives an undulator parameter in the range of K~1 for a high frequency device.*
*A. Zholents, HBEB Workshop, Puerto-Rico, 2013. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO008  
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WEPRO036 Construction and First Magnetic Field Test of a Superconducting Transversal Gradient Undulator for the Laser Wakefield Accelerator in Jena. undulator, electron, laser, radiation 2022
 
  • V. Afonso Rodríguez, A. Bernhard, A.W. Grau, P. Peiffer, R. Rossmanith, M. Weber, C. Widmann, A. Will
    KIT, Karlsruhe, Germany
  • M. Kaluza, M. Nicolai, A. Sävert
    IOQ, Jena, Germany
  • M. Reuter
    HIJ, Jena, Germany
  
  Funding: This work is funded by the German Federal Ministry for Education and Research under contract no. 05K10VK2 and 05K10SJ2.
A superconducting transversal gradient undulator (TGU), tailored to the particular beam properties of the laser wakefield accelerator (LWFA) at the University of Jena, has been designed and constructed at KIT. This undulator in combination with a specialized beam transport line will be employed to produce undulator radiation with natural bandwidth despite the relatively large energy spread of the electrons produced by the LWFA. The fabrication of this undulator and first results of the magnetic field measurement are discussed in this paper. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO036  
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WEPRO118 THz Radiation Generation in Multimode Wakefield Structures radiation, experiment, electron, linac 2248
 
  • S.P. Antipov, S.V. Baryshev, C.-J. Jing, A. Kanareykin, P. Schoessow
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • M.G. Fedurin
    BNL, Upton, Long Island, New York, USA
  • W. Gai, A. Zholents
    ANL, Argonne, Illinois, USA
  • D. Wang
    TUB, Beijing, People's Republic of China
  
  Funding: DOE SBIR
A number of methods for producing sub-picosecond electron bunches have been demonstrated in recent years. A train of these bunches is capable of generating THz radiation via multiple mechanisms like transition, Cherenkov and undulator radiation. We propose to use a bunch train like this to selectively excite a high order mode in a dielectric wakefield structure. This allows us to use wakefield structures that are geometrically larger and easier to fabricate for beam-based THz generation. In this paper we present a THz source design based on this concept and experimental progress to date. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO118  
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THPRO012 Wakefield-based Dechirper Structures for ELBE vacuum, electron, radiation, controls 2882
 
  • F. Reimann, U. van Rienen
    Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
  • U. Lehnert, P. Michel
    HZDR, Dresden, Germany
  
  Funding: Federal Ministry of Education and Research
The efficient reduction of the pulse length and the energy width of electron beams plays a crucial role in the generation of short pulses in the range of sub-picoseconds at future light sources. At the radiation source ELBE in Dresden Rossendorf short pulses are required for coherent THz generation and laser-electron beam interaction experiments such as X-ray Thomson scattering. Energy dechirping can be carried out passively by wakefields generated when the electron beam passes through suitable structures, namely corrugated and dielectrically lined cylindrical pipes or dielectrically lined rectangular waveguides (*,**,***). All structures offer the possibility to tune the resulting wakefield and therefore the resulting energy chirp through a variation of purely geometrical or material parameters. In this paper we present a semi-analytical approach to determine the wakefield in dielectrically lined rectangular waveguide, starting with the expression of the electric field in terms of the structure's eigenmodes.
* Bane, Stupakov, SLAC-PUB-14925 (2012)
** Mosnier, Novokhatski, in: Proceedings of PAC97, Vancouver, Canada, 1997
*** Antipov et al., in: Proceedings of IPAC2012, New Orleans, USA, 2012 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRO012  
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THPRO030 Developments in CLARA Accelerator Design and Simulations FEL, simulation, electron, undulator 2930
 
  • S. Spampinati
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • D. Angal-Kalinin, A.D. Brynes, D.J. Dunning, J.K. Jones, K.B. Marinov, J.W. McKenzie, B.L. Militsyn, N. Thompson, P.H. Williams
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • I.P.S. Martin
    DLS, Oxfordshire, United Kingdom
  
  We present recent developments in the accelerator design of CLARA (Compact Linear Accelerator for Research and Applications), the proposed UK FEL test facility at Daresbury Laboratory. Updates on the electron beam simulations and code comparisons including wakefields are described. Simulations of the effects of geometric wakefields in the small-aperture FEL undulator are shown, as well as further simulations on potential FEL experiments using chirped beams. We also present the results of simulations on post-FEL diagnostics.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRO030  
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THPRO074 Characterization of the Longitudinal Wakefields in the MAX IV Linac linac, simulation, gun, FEL 3050
 
  • O. Karlberg, F. Curbis, S. Thorin, S. Werin
    MAX-lab, Lund, Sweden
  
  In the second part of 2014, the 3GeV linac at the MAX IV laboratory will enter its commissioning stage. Equipped with two guns, the linac will act as a full energy injector for the two storage rings and at the same time provide high brightness pulses to a Short Pulse Facility (SPF). Compression in the linac is done in two double achromats with fixed R56 that relies upon the RF phase introduced energy chirp, which in this case is strongly enhanced by the longitudinal wakefields. Since the longitudinal wakefields plays a major role in the compression and bunch shaping they need to be carefully investigated during the commissioning. In this proceeding we will discuss a measurement technique that will be used during commissioning to characterize the longitudinal wakefields and their precise effects on e.g. the bunch shape and the energy spread. Predictions obtained from particle tracking will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRO074  
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THPME093 Reconstruction of Longitudinal Electrons Bunch Profiles at FACET, SLAC radiation, background, electron, detector 3453
 
  • M. Vieille Grosjean, J. Barros, N. Delerue, S. Jenzer
    LAL, Orsay, France
  • F. Bakkali Taheri, G. Doucas, I.V. Konoplev, A. Reichold
    JAI, Oxford, United Kingdom
  • C.I. Clarke
    SLAC, Menlo Park, California, USA
  
  The E-203 collaboration is testing a device on FACET at SLAC to measure the longitudinal profile of electron bunches using Smith-Purcell radiation. At FACET the electron bunches have an energy of 20GeV and a duration of a few hundred femtoseconds. Smith-Purcell radiation is emitted when a charged particle passes close to the surface of a metallic grating. The set-up installed in FACET consists in four targets (three gratings and a blank) on a carrousel on one side and eleven pyroelectric detectors on the opposite side, the beam passing between. At the moment, the measurement is averaged over a hundred pulses or more. We have studied the stability of the measurement from pulse to pulse and the resolution of the measure depending on the number of grating used.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME093  
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THPRI075 S-Band Structure Study for the MaRIE Project coupling, dipole, impedance, linac 3940
 
  • Z. Li, C. Adolphsen, M.V. Fazio, S.G. Tantawi, L. Xiao
    SLAC, Menlo Park, California, USA
  
  Funding: Work was supported by the US Department of Energy through the LANL/LDRD Program.
The Matter-Radiation Interactions in Extremes (MaRIE) facility proposed at LANL utilizes a 20-GeV electron linac to drive a 50-keV XFEL. Experimental requirements drive a need for multiple photon bunches over time durations of about 10 microsecond produced by a bunch train of interleaving 0.1 nC very low-emittance bunches with 2-nC electron bunches. The linac is required not only to provide high gradient and high efficient acceleration, but also a controlled wakefield profile to maintain the beam quality. In this paper, we explore the feasibility of using the S-Band technology to meet such acceleration requirements. We will present the design optimization and comparison of S-Band structures based on different design considerations. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI075  
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THPRI101 Coupler Kick and Cavity Tilt Effects on Emittance Preservation in Linear Accelerators emittance, cavity, linac, factory 4013
 
  • A.V. Tsakanian, G.A. Amatuni, B. Grigoryan, I.N. Margaryan, V.M. Tsakanov
    CANDLE SRI, Yerevan, Armenia
  
  The effects of the coupler kick and the cavity tilts on the beam dynamics in long linear accelerator are studied. The dispersive and wakefield caused beam emittance dilution are evaluated analytically using two particle model of the beam. The numerical simulations for the European XFEL project are presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRI101  
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