LINAC2018 - Table of Session: MOOP (Monday Oral Posters)

Paper	Title	Page
MOOP01	A 3-gap Booster Cavity to Match Ion Source Potential to RFQ Acceptance
MOPO092	use link to access more material from this paper's primary paper code
	R.E. Laxdal, Z.T. Ang, T. Au, S. Kiy, S.D. Rädel, O. Shelbaya, V. Zvyagintsev TRIUMF, Vancouver, Canada
	The ISAC RFQ can accelerate ions with A/Q ration from 1 to 30 and requires an input energy of 2.04keV/u. The harsh environment of the ISAC on-line ISOL target facility makes it difficult to meet the energy for the heaviest masses. For these cases we have designed and installed a short three gap device that accelerates the beams produced at source potential to match the required energy for RFQ acceptance. The booster cavity operates at 11.7MHz, the RF frequency of the pre-buncher. The device can also be used as a second buncher to augment the acceptance in the RFQ or to improve the acceptance of higher space charge beams. The device will be described and the results of beam measurements will be given.
	Slides MOOP01 [7.627 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO092
About •	paper received ※ 14 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP02	The 7 MeV APF DTL for Proton Therapy
MOPO132	use link to access more material from this paper's primary paper code
	X.C. Xie, D.M. Li, X. Li, Y.H. Pu, J. Qiao, M.H. Zhao, Z.T. Zhao SINAP, Shanghai, People’s Republic of China Y.H. Pu, X.C. Xie, F. Yang Shanghai APACTRON Particle Equipment Company Limited, Shanghai, People’s Republic of China
	Funding: This work is fund by Ministry of Science and Technology of the People’s Repulic of China, under Grant Number 2016YFC0105408 A 7MeV alternating phase focused (APF) drift tube linear (DTL) for proton therapy has been designed, and a design code has been developed based on a sinusoidal synchronous phase formula and a linearly increasing electrode voltage assumption. The design procedure includes the radio frequency quadrupole (RFQ) to drift tube linac (DTL) matching, and end-to-end simulation that conducted by Trace Win. Moreover, a cutting method has been performed to correct the integral electric field deviation of RF gaps.
	Slides MOOP02 [4.219 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO132
About •	paper received ※ 20 August 2018 paper accepted ※ 15 January 2019 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP03	Status of CLARA Front End Commissioning
MOPO035	use link to access more material from this paper's primary paper code
	D. Angal-Kalinin, A.D. Brynespresenter, S.R. Buckley, P.A. Corlett, L.S. Cowie, K.D. Dumbell, D.J. Dunning, P.C. Hornickel, F. Jackson, J.K. Jones, J.W. McKenzie, B.L. Militsyn, A.J. Moss, T.C.Q. Noakes, M.D. Roper, D.J. Scott, B.J.A. Shepherd, E.W. Snedden, N. Thompson, C. Tollervey, D.A. Walsh, T.M. Weston, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom R.J. Cash, R.F. Clarke, G. Cox, C. Hodgkinson, R.J. Smith, J.T.G. Wilson STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom K.D. Dumbell, B.J.A. Shepherd Cockcroft Institute, Warrington, Cheshire, United Kingdom
	CLARA (Compact Linear Accelerator for Research and Applications) is a Free Electron Laser (FEL) test facility under development at Daresbury Laboratory. The principal aim of CLARA is to test advanced FEL schemes which can later be implemented on existing and future short wavelength FELs. We report on the commissioning of the CLARA front end, consisting of a photoinjector and the first linac section, and merger into the existing VELA (Versatile Electron Linear Accelerator) beamline.
	Slides MOOP03 [1.870 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO035
About •	paper received ※ 11 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP04	Status of the 10 MW MBKs during Commissioning of the European XFEL in DESY
MOPO036	use link to access more material from this paper's primary paper code
	V. Vogel (Fogel), Ł. Butkowski, A. Cherepenko, S. Choroba, J. Hartung DESY, Hamburg, Germany
	At present 26 RF stations for European XFEL are in operation. Each of the RF stations consists of a HV modulator located in a separate building on the DESY campus, up to 1600 m long 10 kV HV cables that connect the modulator and the HV pulse transformer located in the underground tunnel, 120kV, 3 m long HV cable connecting the HV pulse transformer and the connection module of the horizontal multi-beam klystron. Two RF stations of the injector have already achieved about 20000 hours of operation, RF stations of the XFEL bunch compressor area have operated up to 11000 hours and in the XFEL main linac up to 8000 hours. To increase the lifetime of the klystrons, we use a fast protection system (KLM) that is based on the comparison of the actual RF shape and the expected RF shape. In the case of a difference exceeding a certain margin, for example, in the case of RF breakdown in a klystron or RF breakdown in a waveguide system, the KLM quickly, shorter than 500 ns, switches off the input RF signal. Thus, it does prevents the vacuum level in the klystron worsen too much or it minimizes the RF overvoltage time at the output windows of the klystron in case of breakdown in waveguides.
	Slides MOOP04 [5.241 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO036
About •	paper received ※ 05 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP05	Coherent Synchrotron Radiation Monitor for Microbunching Instability in XFEL
MOPO040	use link to access more material from this paper's primary paper code
SPWR002	use link to access more material from this paper's primary paper code
	J.H. Ko, I.S. Ko POSTECH, Pohang, Kyungbuk, Republic of Korea H.-S. Kang, C. Kim, G. Kim PAL, Pohang, Kyungbuk, Republic of Korea
	The microbunching instability is an important issue in an X-ray Free Electron Laser (XFEL). The intensity of the FEL can be reduced significantly by the microbunching instability so that the laser heater is widely used to reduce it. In the X-ray Free Electron Laser of the Pohang Accelerator Laboratory (PAL-XFEL), to directly monitor the microbunching instability, a visible CCD camera was included into the coherent radiation monitor (CRM) which uses a pyroelectric detector. It enabled us to measure the microbunching instability more clearly and optimize the FEL lasing in the PAL-XFEL.
	Slides MOOP05 [1.125 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO040
About •	paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP06	Dielectric Waveguide-Based THz Radiator Study for SwissFEL
MOPO034	use link to access more material from this paper's primary paper code
	L. Shi, S. Bettoni, M.M. Dehler, E. Ferrari, B. Hermann, R. Ischebeck, F. Marcellini, S. Reiche, V.G. Thominet PSI, Villigen PSI, Switzerland A.K. Mittelbach Friedrich-Alexander Universität Erlangen-Nuernberg, University Erlangen-Nuernberg LFTE, Erlangen, Germany
	Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 701647 THz pulses have many unique properties in terms of radiation matter interaction. In particular their non-ionizing excitation of phonons in matter makes them a preferred pump for pump-probe studies at free electron lasers. In order to enrich the scientific potentials at SwissFEL (Swiss Free Electron Laser), which can provide ultrashort soft and hard X-ray pulses, we plan to build an economic THz radiator in the range of 1-20 THz by passing the spent electron beam through a dielectric lined tube after the electron beam has generated X-rays. These THz pulses will be transported to the photon user station. Since SwissFEL operates with 2 bunches, serving two beamlines, THz from the first bunch can be used at the user station of the second bunch to allow for pump arrival time before the probe. The core of such a THz generation setup is the dielectric lined tube and the relativistic electron beam. This paper reports on the numerical study of these tubes, in terms of mode structure, energy, pulse length etc, which are essential parameters for the pump-probe experiments. These tubes will be fabricated and tested in the near future in the electron beam line for the soft X-ray of SwissFEL.
	Slides MOOP06 [1.471 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO034
About •	paper received ※ 12 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP07	SRF Gun Development at DESY
MOPO037	use link to access more material from this paper's primary paper code
	E. Vogel, S. Barbanotti, I. Hartl, K. Jensch, D. Klinke, D. Kostin, W.-D. Möller, M. Schmökel, J.K. Sekutowicz, S. Sievers, N. Steinhau-Kühl, A.A. Sulimov, J.H. Thie, H. Weise, L. Winkelmann, B. van der Horst DESY, Hamburg, Germany J.A. Lorkiewicz, R. Nietubyć NCBJ, Świerk/Otwock, Poland J. Smedley BNL, Upton, Long Island, New York, USA J. Teichert HZDR, Dresden, Germany M. Wiencek IFJ-PAN, Kraków, Poland
	A future upgrade of the European XFEL (E-XFEL) foresees an additional cw operation mode increasing the flexibility in the photon beam time structure. This mode requires among others a cw operating photo injector. We believe that using an SRF gun is the preferred approach as the beam parameters of normal conducting pulsed guns can be potentially met by SRF guns operating cw. Since more than a decade DESY in collaboration with TJNAF, NCBJ, BNL, HZB and HZDR performs R&D to develop an all superconducting RF gun with a lead cathode. In the frame of E-XFEL cw upgrade feasibility studies, the SRF-gun R&D program gained more attention and support. Within the next few years we would like to demonstrate the performance of the all superconducting injector required for the E-XFEL upgrade. The selected approach offers advantages w.r.t. the cleanliness of the superconducting surface, but requires a complete disassembly of a cryostat and stripping the gun cavity in a clean room to exchange the cathode. Thus it is practical only when the life time of the cathode is at least several months. In this paper we present the actual status of the R&D program, next steps and the longer term plans.
	Slides MOOP07 [1.966 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO037
About •	paper received ※ 11 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP08	Beam Dynamics Studies and Instrumentation Tests for Bunch Length Measurements at CLEAR
MOPO020	use link to access more material from this paper's primary paper code
	L. Garolfi, M. Bergamaschi, R. Corsini, A. Curcio, S. Döbert, W. Farabolini, D. Gamba, I. Gorgisyan CERN, Geneva, Switzerland C. Bruni, P. Lepercq, H. Purwar, C. Vallerand LAL, Orsay, France W. Farabolini CEA/DSM/IRFU, France
	A new CERN Linear Electron Accelerator for Research (named CLEAR) has been installed as a general-purpose user facility to study novel accelerating techniques, high-gradient structures, instrumentation and irradiation experiments. CLEAR is a flexible accelerator that can provide high quality bunched electron beams with a wide range of beam parameters up to an energy of 220 MeV, offering several testing capabilities. Among all the potential applications, novel accelerating techniques, such as plasma acceleration and THz generation are considered. These applications require shorter bunches, down to the 100 fs level. This paper reports on beam dynamics studies and instrumentation tests to establish a bunch length of this order in CLEAR. The short bunches are generated using adiabatic bunching in the first accelerating structure. For bunch length diagnostic CLEAR is equipped with a streak camera and a transverse deflecting cavity. Alternatively a phase-scan of the last accelerating structure could be used as well to estimate the bunch length. The experimental results with respect to these different techniques are presented and compared with simulations.
	Slides MOOP08 [0.864 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO020
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP09	RF Operation Experience at the European XFEL
MOPO038	use link to access more material from this paper's primary paper code
	J. Branlard, V. Ayvazyan, Ł. Butkowski, M.K. Grecki, M. Hierholzer, M.G. Hoffmann, M. Hoffmann, M. Killenberg, D. Kostin, T. Lamb, L. Lilje, U. Mavrič, M. Omet, S. Pfeiffer, R. Rybaniec, H. Schlarb, Ch. Schmidt, N. Shehzad, V. Vogel, N. Walker DESY, Hamburg, Germany
	After its successful commissioning which took place during the first half of 2017, the European X-ray free electron laser is in now in regular operation delivering photons to users since September 2017. This paper presents an overview on the experience gathered during the first couple of years of operation. In particular, the focus is set on RF operation, maintenance activities, availability and typical failures. A first look on machine performance in terms of RF and beam stability, energy reach, radiation related investigations and microphonics studies will also be presented.
	Slides MOOP09 [2.421 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO038
About •	paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP10	Development of a Linear Electron Accelerator-based Neutron Source for Analysis of Structural Materials
MOPO053	use link to access more material from this paper's primary paper code
	B.E. O’Rourke, T. Fujiwara, K. Kino, R. Kuroda, K. Michishio, H. Ogawa, N. Oshima, D. Sato, N. Sei, R. Suzuki, M. Tanaka, H. Toyokawa, A. Watazu AIST, Tsukuba, Ibaraki, Japan N. Hayashizaki RLNR, Tokyo, Japan T. Muroga, T. Shishido ISMA, Ibaraki, Japan
	Funding: This paper is based on results obtained from Innovative Structural Materials R&D Project commissioned by the New Energy and Industrial Technology Development Organization(NEDO). Neutrons are a powerful probe of structural materials due to their high penetration. As part of the Innovative Structural Materials R&D project funded by the New Energy and Industrial Technology Development Organization (NEDO), the Innovative Structural Materials Association (ISMA) is developing a dedicated, compact electron-accelerator based neutron source at the National Institute of Advanced Industrial Science and Technology (AIST) in Tsukuba, Japan, for the characterization of structural materials. The accelerator is designed to have a maximum electron beam power of 10 kW (~36 MeV and ~275 mA), which will be incident on a water-cooled Ta target. The electron beam will have a maximum pulse length of around 10 μs at a repetition rate of 100 Hz. Neutrons produced through photo-nuclear reactions will be cooled by a decoupled solid methane moderator. Using this pulsed, low-energy neutron beam we plan to perform various imaging spectroscopies of structural materials including Bragg-edge imaging. In this contribution we will describe the dedicated neutron source in more detail, with particular emphasis on the electron accelerator.
	Slides MOOP10 [4.447 MB]
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP11	Design of the High Gradient Negative Harmonic Structure for Compact Ion Therapy Linac
MOPO077	use link to access more material from this paper's primary paper code
	S.V. Kutsaev, R.B. Agustsson, A.Yu. Smirnov, A. Verma RadiaBeam, Santa Monica, California, USA A. Barcikowski, R.L. Fischer, B. Mustapha ANL, Argonne, Illinois, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics, under SBIR grant DE-SC0015717 and Accelerator Stewardship Grant, Proposal No. 0000219678 A novel concept for an Advanced Compact Carbon Ion Linac (ACCIL) that will deliver up to 1 pnA of carbon ions with variable energy from 45 MeV/u to 450 MeV/u in a 45 m footprint, has been developed by Argonne National Laboratory (ANL) in collaboration with RadiaBeam. The ACCIL will have a 35 MV/m real-estate accelerating gradients that became possible to achieve with the development of novel S-band high-gradient structures, capable of providing 50 MV/m accelerating gradients for particles with β>0.3. In particular, a β=0.3 structure based on the novel approach of operation at the first negative spatial harmonic with the increased distance between the accelerating gaps will be presented. This is the first attempt to reach such high gradients at such small velocities. RadiaBeam and ANL have demonstrated the feasibility of building this structure for accelerating carbon ions by means of advanced computer simulations and are currently working towards the fabrication of this structure for high power tests.
	Slides MOOP11 [1.863 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO077
About •	paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP12	A Risk Based Approach to Improving Beam Availability at an Accelerator Facility
MOPO095	use link to access more material from this paper's primary paper code
	W.C. Barkley, M.J. Borden, R.W. Garnett, M.S. Gulley, E.L. Kerstiens, M. Pieck, D. Rees, F.E. Shelley, B.G. Smith LANL, Los Alamos, New Mexico, USA
	Funding: United States Department of Energy This paper describes a risk-based approach to improving beam availability at an accelerator facility. Los Alamos Neutron Science Center (LANSCE), like many other accelerator facilities, was built many years ago and has been re-purposed when new missions were adopted. Many of the upgrades to the accelerator and beamlines allowed improvements in the general area of the upgrade but large-scale, system-wide improvements were never accomplished. Because of this, the facility operates with a mix of old and new equipment of varying condition. Limited budgets have constrained spending for spares procurement making it vital to prioritize those items predicted to have the highest impact to availability, should they fail. A systematic approach is described where equipment is inventoried, condition assessed, rated for potential failure and finally compiled into a risk-based priority list.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO095
About •	paper received ※ 21 September 2018 paper accepted ※ 08 October 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

MOOP01

A 3-gap Booster Cavity to Match Ion Source Potential to RFQ Acceptance

use link to access more material from this paper's primary paper code

R.E. Laxdal, Z.T. Ang, T. Au, S. Kiy, S.D. Rädel, O. Shelbaya, V. Zvyagintsev
TRIUMF, Vancouver, Canada

The ISAC RFQ can accelerate ions with A/Q ration from 1 to 30 and requires an input energy of 2.04keV/u. The harsh environment of the ISAC on-line ISOL target facility makes it difficult to meet the energy for the heaviest masses. For these cases we have designed and installed a short three gap device that accelerates the beams produced at source potential to match the required energy for RFQ acceptance. The booster cavity operates at 11.7MHz, the RF frequency of the pre-buncher. The device can also be used as a second buncher to augment the acceptance in the RFQ or to improve the acceptance of higher space charge beams. The device will be described and the results of beam measurements will be given.

Slides MOOP01 [7.627 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO092

About •

paper received ※ 14 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP02

The 7 MeV APF DTL for Proton Therapy

MOPO132

use link to access more material from this paper's primary paper code

X.C. Xie, D.M. Li, X. Li, Y.H. Pu, J. Qiao, M.H. Zhao, Z.T. Zhao
SINAP, Shanghai, People’s Republic of China
Y.H. Pu, X.C. Xie, F. Yang
Shanghai APACTRON Particle Equipment Company Limited, Shanghai, People’s Republic of China

Funding: This work is fund by Ministry of Science and Technology of the People’s Repulic of China, under Grant Number 2016YFC0105408
A 7MeV alternating phase focused (APF) drift tube linear (DTL) for proton therapy has been designed, and a design code has been developed based on a sinusoidal synchronous phase formula and a linearly increasing electrode voltage assumption. The design procedure includes the radio frequency quadrupole (RFQ) to drift tube linac (DTL) matching, and end-to-end simulation that conducted by Trace Win. Moreover, a cutting method has been performed to correct the integral electric field deviation of RF gaps.

Slides MOOP02 [4.219 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO132

About •

paper received ※ 20 August 2018 paper accepted ※ 15 January 2019 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP03

Status of CLARA Front End Commissioning

MOPO035

use link to access more material from this paper's primary paper code

D. Angal-Kalinin, A.D. Brynespresenter, S.R. Buckley, P.A. Corlett, L.S. Cowie, K.D. Dumbell, D.J. Dunning, P.C. Hornickel, F. Jackson, J.K. Jones, J.W. McKenzie, B.L. Militsyn, A.J. Moss, T.C.Q. Noakes, M.D. Roper, D.J. Scott, B.J.A. Shepherd, E.W. Snedden, N. Thompson, C. Tollervey, D.A. Walsh, T.M. Weston, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
R.J. Cash, R.F. Clarke, G. Cox, C. Hodgkinson, R.J. Smith, J.T.G. Wilson
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
K.D. Dumbell, B.J.A. Shepherd
Cockcroft Institute, Warrington, Cheshire, United Kingdom

CLARA (Compact Linear Accelerator for Research and Applications) is a Free Electron Laser (FEL) test facility under development at Daresbury Laboratory. The principal aim of CLARA is to test advanced FEL schemes which can later be implemented on existing and future short wavelength FELs. We report on the commissioning of the CLARA front end, consisting of a photoinjector and the first linac section, and merger into the existing VELA (Versatile Electron Linear Accelerator) beamline.

Slides MOOP03 [1.870 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO035

About •

paper received ※ 11 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP04

Status of the 10 MW MBKs during Commissioning of the European XFEL in DESY

MOPO036

use link to access more material from this paper's primary paper code

V. Vogel (Fogel), Ł. Butkowski, A. Cherepenko, S. Choroba, J. Hartung
DESY, Hamburg, Germany

At present 26 RF stations for European XFEL are in operation. Each of the RF stations consists of a HV modulator located in a separate building on the DESY campus, up to 1600 m long 10 kV HV cables that connect the modulator and the HV pulse transformer located in the underground tunnel, 120kV, 3 m long HV cable connecting the HV pulse transformer and the connection module of the horizontal multi-beam klystron. Two RF stations of the injector have already achieved about 20000 hours of operation, RF stations of the XFEL bunch compressor area have operated up to 11000 hours and in the XFEL main linac up to 8000 hours. To increase the lifetime of the klystrons, we use a fast protection system (KLM) that is based on the comparison of the actual RF shape and the expected RF shape. In the case of a difference exceeding a certain margin, for example, in the case of RF breakdown in a klystron or RF breakdown in a waveguide system, the KLM quickly, shorter than 500 ns, switches off the input RF signal. Thus, it does prevents the vacuum level in the klystron worsen too much or it minimizes the RF overvoltage time at the output windows of the klystron in case of breakdown in waveguides.

Slides MOOP04 [5.241 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO036

About •

paper received ※ 05 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP05

Coherent Synchrotron Radiation Monitor for Microbunching Instability in XFEL

MOPO040

use link to access more material from this paper's primary paper code

SPWR002

use link to access more material from this paper's primary paper code

J.H. Ko, I.S. Ko
POSTECH, Pohang, Kyungbuk, Republic of Korea
H.-S. Kang, C. Kim, G. Kim
PAL, Pohang, Kyungbuk, Republic of Korea

The microbunching instability is an important issue in an X-ray Free Electron Laser (XFEL). The intensity of the FEL can be reduced significantly by the microbunching instability so that the laser heater is widely used to reduce it. In the X-ray Free Electron Laser of the Pohang Accelerator Laboratory (PAL-XFEL), to directly monitor the microbunching instability, a visible CCD camera was included into the coherent radiation monitor (CRM) which uses a pyroelectric detector. It enabled us to measure the microbunching instability more clearly and optimize the FEL lasing in the PAL-XFEL.

Slides MOOP05 [1.125 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO040

About •

paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP06

Dielectric Waveguide-Based THz Radiator Study for SwissFEL

MOPO034

use link to access more material from this paper's primary paper code

L. Shi, S. Bettoni, M.M. Dehler, E. Ferrari, B. Hermann, R. Ischebeck, F. Marcellini, S. Reiche, V.G. Thominet
PSI, Villigen PSI, Switzerland
A.K. Mittelbach
Friedrich-Alexander Universität Erlangen-Nuernberg, University Erlangen-Nuernberg LFTE, Erlangen, Germany

Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 701647
THz pulses have many unique properties in terms of radiation matter interaction. In particular their non-ionizing excitation of phonons in matter makes them a preferred pump for pump-probe studies at free electron lasers. In order to enrich the scientific potentials at SwissFEL (Swiss Free Electron Laser), which can provide ultrashort soft and hard X-ray pulses, we plan to build an economic THz radiator in the range of 1-20 THz by passing the spent electron beam through a dielectric lined tube after the electron beam has generated X-rays. These THz pulses will be transported to the photon user station. Since SwissFEL operates with 2 bunches, serving two beamlines, THz from the first bunch can be used at the user station of the second bunch to allow for pump arrival time before the probe. The core of such a THz generation setup is the dielectric lined tube and the relativistic electron beam. This paper reports on the numerical study of these tubes, in terms of mode structure, energy, pulse length etc, which are essential parameters for the pump-probe experiments. These tubes will be fabricated and tested in the near future in the electron beam line for the soft X-ray of SwissFEL.

Slides MOOP06 [1.471 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO034

About •

paper received ※ 12 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP07

SRF Gun Development at DESY

MOPO037

use link to access more material from this paper's primary paper code

E. Vogel, S. Barbanotti, I. Hartl, K. Jensch, D. Klinke, D. Kostin, W.-D. Möller, M. Schmökel, J.K. Sekutowicz, S. Sievers, N. Steinhau-Kühl, A.A. Sulimov, J.H. Thie, H. Weise, L. Winkelmann, B. van der Horst
DESY, Hamburg, Germany
J.A. Lorkiewicz, R. Nietubyć
NCBJ, Świerk/Otwock, Poland
J. Smedley
BNL, Upton, Long Island, New York, USA
J. Teichert
HZDR, Dresden, Germany
M. Wiencek
IFJ-PAN, Kraków, Poland

A future upgrade of the European XFEL (E-XFEL) foresees an additional cw operation mode increasing the flexibility in the photon beam time structure. This mode requires among others a cw operating photo injector. We believe that using an SRF gun is the preferred approach as the beam parameters of normal conducting pulsed guns can be potentially met by SRF guns operating cw. Since more than a decade DESY in collaboration with TJNAF, NCBJ, BNL, HZB and HZDR performs R&D to develop an all superconducting RF gun with a lead cathode. In the frame of E-XFEL cw upgrade feasibility studies, the SRF-gun R&D program gained more attention and support. Within the next few years we would like to demonstrate the performance of the all superconducting injector required for the E-XFEL upgrade. The selected approach offers advantages w.r.t. the cleanliness of the superconducting surface, but requires a complete disassembly of a cryostat and stripping the gun cavity in a clean room to exchange the cathode. Thus it is practical only when the life time of the cathode is at least several months. In this paper we present the actual status of the R&D program, next steps and the longer term plans.

Slides MOOP07 [1.966 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO037

About •

paper received ※ 11 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP08

Beam Dynamics Studies and Instrumentation Tests for Bunch Length Measurements at CLEAR

MOPO020

use link to access more material from this paper's primary paper code

L. Garolfi, M. Bergamaschi, R. Corsini, A. Curcio, S. Döbert, W. Farabolini, D. Gamba, I. Gorgisyan
CERN, Geneva, Switzerland
C. Bruni, P. Lepercq, H. Purwar, C. Vallerand
LAL, Orsay, France
W. Farabolini
CEA/DSM/IRFU, France

A new CERN Linear Electron Accelerator for Research (named CLEAR) has been installed as a general-purpose user facility to study novel accelerating techniques, high-gradient structures, instrumentation and irradiation experiments. CLEAR is a flexible accelerator that can provide high quality bunched electron beams with a wide range of beam parameters up to an energy of 220 MeV, offering several testing capabilities. Among all the potential applications, novel accelerating techniques, such as plasma acceleration and THz generation are considered. These applications require shorter bunches, down to the 100 fs level. This paper reports on beam dynamics studies and instrumentation tests to establish a bunch length of this order in CLEAR. The short bunches are generated using adiabatic bunching in the first accelerating structure. For bunch length diagnostic CLEAR is equipped with a streak camera and a transverse deflecting cavity. Alternatively a phase-scan of the last accelerating structure could be used as well to estimate the bunch length. The experimental results with respect to these different techniques are presented and compared with simulations.

Slides MOOP08 [0.864 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO020

About •

paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP09

RF Operation Experience at the European XFEL

MOPO038

use link to access more material from this paper's primary paper code

J. Branlard, V. Ayvazyan, Ł. Butkowski, M.K. Grecki, M. Hierholzer, M.G. Hoffmann, M. Hoffmann, M. Killenberg, D. Kostin, T. Lamb, L. Lilje, U. Mavrič, M. Omet, S. Pfeiffer, R. Rybaniec, H. Schlarb, Ch. Schmidt, N. Shehzad, V. Vogel, N. Walker
DESY, Hamburg, Germany

After its successful commissioning which took place during the first half of 2017, the European X-ray free electron laser is in now in regular operation delivering photons to users since September 2017. This paper presents an overview on the experience gathered during the first couple of years of operation. In particular, the focus is set on RF operation, maintenance activities, availability and typical failures. A first look on machine performance in terms of RF and beam stability, energy reach, radiation related investigations and microphonics studies will also be presented.

Slides MOOP09 [2.421 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO038

About •

paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP10

Development of a Linear Electron Accelerator-based Neutron Source for Analysis of Structural Materials

MOPO053

use link to access more material from this paper's primary paper code

B.E. O’Rourke, T. Fujiwara, K. Kino, R. Kuroda, K. Michishio, H. Ogawa, N. Oshima, D. Sato, N. Sei, R. Suzuki, M. Tanaka, H. Toyokawa, A. Watazu
AIST, Tsukuba, Ibaraki, Japan
N. Hayashizaki
RLNR, Tokyo, Japan
T. Muroga, T. Shishido
ISMA, Ibaraki, Japan

Funding: This paper is based on results obtained from Innovative Structural Materials R&D Project commissioned by the New Energy and Industrial Technology Development Organization(NEDO).
Neutrons are a powerful probe of structural materials due to their high penetration. As part of the Innovative Structural Materials R&D project funded by the New Energy and Industrial Technology Development Organization (NEDO), the Innovative Structural Materials Association (ISMA) is developing a dedicated, compact electron-accelerator based neutron source at the National Institute of Advanced Industrial Science and Technology (AIST) in Tsukuba, Japan, for the characterization of structural materials. The accelerator is designed to have a maximum electron beam power of 10 kW (~36 MeV and ~275 mA), which will be incident on a water-cooled Ta target. The electron beam will have a maximum pulse length of around 10 μs at a repetition rate of 100 Hz. Neutrons produced through photo-nuclear reactions will be cooled by a decoupled solid methane moderator. Using this pulsed, low-energy neutron beam we plan to perform various imaging spectroscopies of structural materials including Bragg-edge imaging. In this contribution we will describe the dedicated neutron source in more detail, with particular emphasis on the electron accelerator.

Slides MOOP10 [4.447 MB]

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP11

Design of the High Gradient Negative Harmonic Structure for Compact Ion Therapy Linac

MOPO077

use link to access more material from this paper's primary paper code

S.V. Kutsaev, R.B. Agustsson, A.Yu. Smirnov, A. Verma
RadiaBeam, Santa Monica, California, USA
A. Barcikowski, R.L. Fischer, B. Mustapha
ANL, Argonne, Illinois, USA

Funding: This work was supported by the U.S. Department of Energy, Office of High Energy Physics, under SBIR grant DE-SC0015717 and Accelerator Stewardship Grant, Proposal No. 0000219678
A novel concept for an Advanced Compact Carbon Ion Linac (ACCIL) that will deliver up to 1 pnA of carbon ions with variable energy from 45 MeV/u to 450 MeV/u in a 45 m footprint, has been developed by Argonne National Laboratory (ANL) in collaboration with RadiaBeam. The ACCIL will have a 35 MV/m real-estate accelerating gradients that became possible to achieve with the development of novel S-band high-gradient structures, capable of providing 50 MV/m accelerating gradients for particles with β>0.3. In particular, a β=0.3 structure based on the novel approach of operation at the first negative spatial harmonic with the increased distance between the accelerating gaps will be presented. This is the first attempt to reach such high gradients at such small velocities. RadiaBeam and ANL have demonstrated the feasibility of building this structure for accelerating carbon ions by means of advanced computer simulations and are currently working towards the fabrication of this structure for high power tests.

Slides MOOP11 [1.863 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO077

About •

paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOP12

A Risk Based Approach to Improving Beam Availability at an Accelerator Facility

MOPO095

use link to access more material from this paper's primary paper code

W.C. Barkley, M.J. Borden, R.W. Garnett, M.S. Gulley, E.L. Kerstiens, M. Pieck, D. Rees, F.E. Shelley, B.G. Smith
LANL, Los Alamos, New Mexico, USA

Funding: United States Department of Energy
This paper describes a risk-based approach to improving beam availability at an accelerator facility. Los Alamos Neutron Science Center (LANSCE), like many other accelerator facilities, was built many years ago and has been re-purposed when new missions were adopted. Many of the upgrades to the accelerator and beamlines allowed improvements in the general area of the upgrade but large-scale, system-wide improvements were never accomplished. Because of this, the facility operates with a mix of old and new equipment of varying condition. Limited budgets have constrained spending for spares procurement making it vital to prioritize those items predicted to have the highest impact to availability, should they fail. A systematic approach is described where equipment is inventoried, condition assessed, rated for potential failure and finally compiled into a risk-based priority list.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO095

About •

paper received ※ 21 September 2018 paper accepted ※ 08 October 2018 issue date ※ 18 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)