IBIC2012 - List of Keywords (laser)

Paper	Title	Other Keywords	Page
MOIA02	Progress of Beam Instumentation in J-PARC Linac	linac, proton, DTL, operation	1
	A. Miura JAEA/J-PARC, Tokai-mura, Japan
	J-PARC, one of the high intensity proton accelerators, achieved the output power of 300 kW at the downstream rapid cycling synchrotron with a beam energy of 181 MeV and a beam current of 15 mA. When an upgrade of an ion source which can provide 50 mA and the installation of the additional acceleration cavities for the energy upgrade up to 400 MeV are completed, output power can reach 1MW. To meet with the requirements of the high intensity beam diagnostics, we prepare several measures against high intensity proton related issues. The following subjects have been reported among many subjects: development of strip-line type beam position monitors, beam current monitors, phase monitors and transverse profile monitors. And the subjects of the beam diagnostic for the energy upgraded linac including the longitudinal beam profile monitor and the developing laser based profile monitor will be mentioned. A big earthquake occurred on May 11, 2011. We successfully recovered to have commercial operation, but a partial recovery is still undergoing. Influence of the quake on the J-PARC linac is also mentioned.
	Slides MOIA02 [2.133 MB]

MOCC03	The First Electron Bunch Measurement by means of DAST Organic EO Crystals	electron, FEL, real-time, operation	29
	Y. Okayasu, S. Matsubara, T. Togashi JASRI/SPring-8, Hyogo-ken, Japan M. Aoyama JAEA/Kansai, Kyoto, Japan A. Iwasaki, S. Owada The University of Tokyo, Tokyo, Japan T. Matsukawa RIKEN ASI, Sendai, Miyagi, Japan H. Minamide RIKEN Advanced Science Insititute, Sendai, Miyagi, Japan K. Ogawa, T. Sato, H. Tomizawa RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan E. Takahashi RIKEN, Saitama, Japan
	Pilot user experiments via the seeded FEL have been demonstrated at the Prototype Test Accelerator (VUV-FEL), SPring-8 from July, 2012. A precise measurement of the electron bunch charge distribution (BCD) is crucial key to keep spatial and temporal overlaps between high-order harmonic (HH) laser pulses and electron bunches. R&D of the 3D-BCD monitor with a single-shot detection has been extensively promoted at SPring-8. The monitor adopts a spectral decoding based Electro-Optic (EO) sampling technique that is non-destructive and enables real-time reconstruction of the 3D-BCD with a temporal resolution of 30- to 40-fs (FWHM). So far, such EO sampling based BCD monitors have been developed by utilizing inorganic EO crystals such as ZnTe and their temporal resolutions are limited to ~130 fs (FWHM). As a part of this project, the first BCD measurement with an organic EO crystal DAST has been successfully demonstrated at the facility. Signal intensities, temporal resolutions and radiation related issues via both ZnTe and DAST are discussed.
	Slides MOCC03 [3.912 MB]

MOPA17	Modular Logarithmic Amplifier Beam Position Monitor Readout System at the University of Hawai'i	electron, GUI, FEL, detector	90
	B.T. Jacobson, M.R. Hadmack, J. Madey, P. Niknejadi University of Hawaii, Honolulu, HI, USA
	High brightness electron beams for inverse Compton backscatter photon sources driven by thermionic microwave guns require real-time position measurements in order to achieve the spatial and temporal coincidence necessary to ensure statistically measurable signals. True logarithmic amplifiers are more adequately suited to signal comparison than are σ-delta methods. A low-cost, modular and scalable readout and data acquisition system for strip-line beam position monitors utilizing the AD640 log-amp is being developed at University of Hawai'i MkV Linear Accelerator and Free Electron Laser Lab. Initial measurements and prototyping of the hardware is complete with commissioning and deployment of the system currently ongoing. We present the methodology and early results of this project.

MOPA20	Development of 3D EO-Sampling System for the Ultimate Temporal Resolution	FEL, electron, timing, feedback	98
	K. Ogawa, H. Tomizawa RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan S. Matsubara, Y. Okayasu JASRI/SPring-8, Hyogo, Japan
	We have been developing three dimensional bunch charge distribution (3D-BCD) monitor for FEL seeded with high-order harmonic (HH) pulse. 3D-BCD is based on EO-sampling technique with multiple EO crystal detectors in the manner of spectral decoding. Using this 3D-EO sampling technique, the positioning and timing of electron bunch is obtained in real-time with non-destructive measurement. For obtaining the high temporal resolution, an octave broadband probe laser with linear chirp rate of 1 fs/nm is required. We are developing an EO-probe laser pulse with ~10 μJ pulse energy and the bandwidth over 300 nm (FWHM). For meet these bandwidth and pulse energy, this EO-probe pulse is using a supercontinuum generated by photonic crystal fiber (PCF) and amplified with optical parametric amplification (OPA). Especially, for amplification with maintaining octave bandwidth, non-collinear OPA (NOPA) using BBO crystal and a pump source with a wavelength of 450 nm are adopted. The EO-probe pulse energy of 10 μJ provides for high S/N ratio to each detector and the bandwidth of 300 nm with 300 fs pulse duration allows the measurement for the 30 fs electron bunch duration (FWHM).

MOPA43	RF Front end for High Bandwidth Bunch Arrival Time Monitors in Free-Electron Lasers at DESY	pick-up, simulation, operation, electron	157
	A. Penirschke, A. Angelovski, M. Hansli, R. Jakoby TU Darmstadt, Darmstadt, Germany M. Bousonville, M.K. Czwalinna, H. Schlarb, C. Sydlo DESY, Hamburg, Germany A. Kuhl Uni HH, Hamburg, Germany S. Schnepp IFH, Zurich, Switzerland T. Weiland TEMF, TU Darmstadt, Darmstadt, Germany
	Funding: Funded by the Federal Ministry of Education and Research (BMBF): 05K10RDA "Weiterentwickung eines Ankunftszeitmonitors" The Free-Electron Laser in Hamburg FLASH is equipped with Bunch Arrival-time Monitors (BAMs) that use an electro-optical detection scheme to modulate the intensity of the femtosecond laser pulse train with the pickup signals (). The achieved resolution of the existing BAMs are less than 10 fs for bunch charges higher than 500 pC. For lower bunch charges the time resolution drops significantly. Increased demands for low bunch charge operation modes of 20 pC and less at FLASH II and the European X-ray Free-Electron Laser XFEL require an upgrade of the existing beam diagnostic equipment. High bandwidth BAMs with newly developed cone-shaped pickups () promise sub-10 fs time resolution for both, the high and low bunch charge operation mode. This paper addresses the RF signal path of the high bandwidth BAMs for FLASH II and XFEL. It comprises radiation resistant coaxial cables, combiners and limiters up to a frequency of 40 GHz from the pickup electrodes to the Electro-optical Mach-Zehnder type modulator (EOM). Detailed investigations of the signal path using measurements and simulations with AWR Microwave Office allows for a good prediction of the signal quality and shape at the EOM. () F. Löhl et al., Phys. Rev. Lett. 104,144801 (2010) (**) A. Angelovski et al. in Proceedings of the International Particle Accelerator Conference (IPAC2011), San Sebastian, Spain, 2011, p.1177

MOPA46	Realization and Measurements of Cone-shaped Pickups for Bunch Arrival-time Monitors for FLASH and XFEL	pick-up, simulation, electron, free-electron-laser	165
	A. Angelovski, M. Hansli, R. Jakoby, A. Penirschke TU Darmstadt, Darmstadt, Germany M. Bousonville, M.K. Czwalinna, H. Schlarb, C. Sydlo DESY, Hamburg, Germany A. Kuhl Uni HH, Hamburg, Germany S. Schnepp IFH, Zurich, Switzerland T. Weiland TEMF, TU Darmstadt, Darmstadt, Germany
	Funding: Funded by the Federal Ministry of Education and Research (BMBF): 05K10RDA "Weiterentwickung eines Ankunftszeitmonitors" At the Free Electron Laser FLASH at DESY, the installed Bunch Arrival-time Monitors (BAMs) use an electro-optical detection scheme for arrival-time measurements. The achieved time resolution is in the sub-10 fs range for bunch charges higher than 500 pC. The extension of FLASH II and the European X-ray Free Electron Laser Project (XFEL) foresees a low charge operation mode with bunch charge of 20 pC or less. The time resolution of the BAMs significantly drops as the bunch charge reduces (). By expanding the bandwidth of the pickups one can increase the time resolution at low charges. In this paper, we present the characterization results of the manufactured cone-shaped pickups introduced in () with a bandwidth up to 40 GHz. The pickups mounted in a vacuum body exhibit four-fold rotational symmetry with respect to the beam pipe. Due to different beam pipe apertures for FLASH and XFEL, two bodies are manufactured. The rf properties of the mounted pickups in case of open and sealed body as well as the pickups separately are measured and compared to the simulation results obtained by CST STUDIO SUITE®. ()M. K. Bock et al. in Proceedings of DIPAC 2011, Hamburg, Germany, 2011, p.365 (**)A. Angelovski et al. in Proceedings of IPAC 2011, San Sebastian, Spain, 2011, p.1177

MOPA49	EO-sampling-based Temporal Overlap Control System for an HH Seeded FEL	FEL, electron, operation, timing	176
	S. Matsubara RIKEN/SPring-8, Hyogo, Japan M. Aoyama JAEA/Kansai, Kyoto, Japan A. Iwasaki, S. Owada The University of Tokyo, Tokyo, Japan K. Ogawa, T. Sato, H. Tomizawa RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan Y. Okayasu, T. Togashi, T. Watanabe JASRI/SPring-8, Hyogo-ken, Japan E. Takahashi RIKEN, Saitama, Japan
	FELs have greatly interested for the short-wavelength region. However, their temporal profile and frequency spectra have shot-to-shot fluctuation by a SASE process. One of the promising approached for the problems is a seeded FEL scheme by using a full-coherent light source. The seeded FEL has been demonstrated in the EUV region by employ the high-order harmonics (HH) generation from an external laser source at the SCSS test-accelerator in the SPring-8. It is important for the HH-seeded FEL scheme to synchronize and overlap between the seeding laser pulse and the electron bunch. Their timing difference and laser spatial pointing is drifting. Therefore, a timing feedback and non-destructive monitor are necessary to operate seeded FEL continuously. We have constructed the timing monitor based on Electro-Optic (EO) sampling which is measure the timing difference the seeded laser pulse and the electron bunch simultaneously with the seeded FEL process. The probe laser pulse for the EO-sampling system is optically split from the common external HH laser driver for the seeded FEL. The EO-sampling system is able to use timing feedback for continual operation of the HH-seededFEL.

MOPB79	Design of a High-precision Fast Wire Scanner for the SPS at CERN	vacuum, operation, booster, acceleration	259
	R. Veness, N. Chritin, B. Dehning, J. Emery, J.F. Herranz Alvarez, M. Koujili, S. Samuelsson, J.L. Sirvent Blasco CERN, Geneva, Switzerland
	Studies are going on of a new wire scanner concept. All moving parts are inside the beam vacuum and it is specified for use in all the machines across the CERN accelerator complex. Key components have been developed and tested. Work is now focussing on the installation of a prototype for test in the Super Proton Synchrotron (SPS) accelerator. This article presents the specification of the device and constraints on the design for integration in the different accelerators at CERN. The design issues of the mechanical components are discussed and optimisation work shown. Finally, the prototype design, integrating the several components into the vacuum tank is presented.

MOPB82	Bunch-Compressor Transverse Profile Monitors of the SwissFEL Injector Test Facility	electron, operation, vacuum, undulator	271
	G.L. Orlandi, M. Aiba, S. Bettoni, B. Beutner, H. Brands, R. Ischebeck, P. Peier, E. Prat, T. Schietinger, V. Schlott, V.G. Thominet PSI, Villigen PSI, Switzerland C. Gerth DESY, Hamburg, Germany
	The 250 MeV SwissFEL Injector Test Facility (SITF) is the test bed of the future 5.7 GeV SwissFEL linac that will drive a coherent FEL light source in the wavelength range 7-0.7 and 0.7-0.1 nm. Aim of the SITF is to demonstrate the technical feasibility of producing and measuring 10 or 200pC electron bunches with normalized emittance down to 0.25 μm. A further goal is to demonstrate that the electron beam quality is preserved in the acceleration process, in the X-Band linearizer and the magnetic compression from about 10 ps down to 200 fs. The SITF movable magnetic bunch-compressor is equipped with several CCD/CMOS cameras for monitoring the beam transverse profile and determining the beam energy spread: a Ce:YAG screen and an OTR screen camera at the mid-point of the bunch compressor and a SR camera imaging in the visible the Synchrotron Radiation emitted by the electron beam crossing the third dipole. Results on the commissioning of such instrumentations, in particular in the low charge limit, and measurements of the beam energy spread vs. the compression factor will be presented.

TUCC04	Measurement of Nanometer Electron Beam Sizes with Laser Interference using IPBSM	optics, detector, alignment, photon	310
	J.N. Yan, S. Komamiya, M. Oroku, T.S. Suehara, Y. Yamaguchi, T. Yamanaka University of Tokyo, Tokyo, Japan S. Araki, T. Okugi, T. Tauchi, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan Y. Kamiya ICEPP, Tokyo, Japan
	At ATF2, the Local Chromaticity Correction focusing scheme is to be verified through realizing its design vertical e^- beam size (σy ) of 37 nm. The 'IPBSM', installed at ATF2's virtual IP, is the only existing beam size monitor capable of measuring σy < 100 nm, making it indispensable for ATF's goals and R&D at future LCs. This owes to a novel technique of colliding e^- beam against laser interference fringes. σy is derived from the modulation depth of resulting Compton photons, which is large for small σy. The measurable range from O(10) nm ~ a few μm, is controlled by switching between laser crossing angles θ = 174° , 30°, and 2° - 8° . In early 2011, measuring σy < 300 nm was hindered by an immense earthquake and heavy signal jitters. The ensuing recovery and upgrades stabilized the laser system and improved resolution to 5%. In spring 2012, we commissioned advanced crossing angle modes by consistently measuring σy ≥ 150 nm. Our goals for the autumn 2012 run is to stably measure σy < 50 nm. Major hardware upgrades during the summer aim at more reliable alignment and optimization of specialized functions to suppress bias factors.
	Slides TUCC04 [10.535 MB]

TUPA43	First Operation of the Electro-optical Sampling Diagnostics of the FERMI@Elettra FEL	electron, FEL, alignment, vacuum	449
	M. Veronese, A. Abrami, E. Allaria, M. Bossi, M.B. Danailov, M. Ferianis, L. Fröhlich, S. Grulja, M. Predonzani, F. Rossi, G. Scalamera, C. Spezzani, M. Trovò, M. Tudor Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	The FERMI@Elettra seeded FEL has demanding specifications in terms of longitudinal properties of the electron beam. Several diagnostics are installed along the linac. At the entrance of the FEL1 undulator chain an electro optical sampling (EOS) station based on the spatial encoding scheme is installed. The EOS provides both time jitter and longitudinal profile measurements in a non-destructive way. The layout of this system is described and the first operational measurement results obtained are reported. The paper includes also the capability of this diagnostics to perform the temporal coarse alignment of the seed laser to the electron beam. Finally a discussion on the future developments foreseen for this system is given.

TUPA44	Status of the LCLS Experiment Timing System	timing, experiment, electron, feedback	453
	J.C. Frisch, C. Bostedt, R.N. Coffee, A.R. Fry, N. Hartmann, J. May, D.J. Nicholson, S. Schorb, S.R. Smith SLAC, Menlo Park, California, USA
	Funding: Work Supported by Department of Energy Contract DE AC03 76SF00515 X-ray / optical laser pump - probe experiments are used for a significant fraction of the scientific work performed at LCLS. The experimental laser systems are locked to the timing of the electron beam through a combination of RF and optical fiber based systems. The remaining ~100 femtosecond RMS jitter of the X-rays relative to the optical laser is measured shot-to-shot by both a RF timing detector, and by direct X-ray to optical cross-correlation, and the result is used to correct the experiment timing to 10s of femtoseconds. We present the present status of the system and plans for future upgrades.

TUPA47	Middle-infrared Prism Spectrometer for Single-shot Bunch Length Diagnostics at the LCLS	detector, optics, diagnostics, radiation	463
	T.J. Maxwell, Y. Ding, A.S. Fisher, J.C. Frisch, H. Loos SLAC, Menlo Park, California, USA C. Behrens DESY, Hamburg, Germany
	Funding: Work supported in part by US Department of Energy contract number DE-AC02-76SF00515. Modern high-brightness accelerators such as laser plasma wakefield and free-electron lasers continue the drive to ever-shorter bunches. At low-charge (< 20 pC), bunches as short as 10 fs are reported at the Linac Coherent Light Source (LCLS). Advanced time-resolved diagnostics approaching the fs-level have been proposed requiring the support of rf-deflectors, modern laser systems, or other complex systems. Though suffering from a loss of phase information, spectral diagnostics remain appealing by comparison as compact, low-cost systems suitable for deployment in beam dynamics studies and operations instrumentation. Progress in mid-IR imaging and detection of the corresponding micrometer-range power spectrum has led to the continuing development of a single-shot, 1.2 - 40 micrometer prism spectrometer for ultra-short bunch length monitoring. In this paper we report further analysis and experimental progress on the spectrometer installation at LCLS.

TUPB48	Beam Instrumentation for the COSY Electron Cooler	electron, gun, detector, controls	468
	V. Kamerdzhiev, L.J. Mao, K. Reimers FZJ, Jülich, Germany E.A. Bekhtenev, V.N. Bocharov, M.I. Bryzgunov, A.V. Bubley, A.P. Denisov, G.V. Karpov, V.M. Panasyuk, V.V. Parkhomchuk, V.B. Reva BINP SB RAS, Novosibirsk, Russia J. Dietrich HIM, Mainz, Germany
	The report deals with beam instrumentation of the electron cooler for COSY storage ring. The electron cooler is an electrostatic accelerator designed for beam energy up to 2 MeV and electron current up to 3 A with recuperation. The electron beam is immersed in longitudinal magnetic field so the electron motion is strongly magnetized. The control electrode in the electron gun is composed of four electrically isolated sectors. Applying AC voltage to one sector allows tracing of motion of that particular part of the beam. The electron beam shape is registered with the combination of 4-sector electron gun and the BPMs. This method allows observing both dipole and quadruple (galloping) modes of electron beam oscillation. Compass probe for measuring and tuning the direction of magnetic field in the cooling section is described. A profile monitor based on a few small Faraday cups for measuring distribution of the electron beam is presented.

TUPB57	Extreme Light Infrastructure (ELI Beamlines) - Research and Technology with new Ultra-short Pulse Intense Laser driven Sources of Energetic Photons and Charged Particles	electron, proton, plasma, target	482
	L. Pribyl, L. Juha, G. Korn, T. Levato, B. Rus, S. Ter-Avetisyan Czech Republic Academy of Sciences, Institute of Physics, Prague, Czech Republic D. Margarone INFN/LNS, Catania, Italy S. Sebban LOA, Palaiseau, France
	Funding: Czech Science Foundation (Project No. P205/11/1165), the Czech Republic's Ministry of Education, Youth and Sports to ELI-Beamlines (CZ.1.05/1.1.00/483/02.0061) and OPVK CZ.1.07/2.3.00/20.0087). We will be giving an overview on the development of the 'ELI-Beamline facility', which will be a high-energy, repetition-rate laser pillar of the ELI (Extreme Light Infrastructure) project. It will be an international facility for both academic and applied research, slated to provide user capability since the beginning of 2016. The main purpose of the facility is the generation and applications of laser driven high-brightness X-ray sources and accelerated particles (electrons, protons and ions). The laser system will be delivering pulses with length ranging between 10 and 150 fs and will provide high-energy Petawatt and 10-PW peak powers. We will concentrate on the development of short photon wavelength (20 eV-100 keV) laser driven sources and their practical implementation. The sources are either based on direct interaction of the laser beam with a gaseous or solid target or will first accelerate electrons which then will interact with laser produced wigglers or directly injected into undulators. The main planned short pulse laser driven x-ray sources and their parameters will be presented together with requirements on the relevant beam detectors.

TUPB76	Intra Undulator Screen Diagnostics for the FERMI@Elettra FEL	FEL, electron, undulator, radiation	519
	M. Veronese, A. Abrami, E. Allaria, M. Bossi, A. Bucconi, M. De Marco, M. Ferianis, L. Fröhlich, L. Giannessi, S. Grulja, R. Sauro, C. Spezzani, M. Tudor Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy T. Borden FRIB, East Lansing, Michigan, USA F. Cianciosi ESRF, Grenoble, France
	The FERMI@Elettra seeded FEL poses demanding requirements in terms of intra undulator diagnostics due to the short wavelength of its FEL radiation and to the coexistence of the electron and photon FEL beams. An advanced multi-beam screen system has equipped both FEL1 and FEL2. The system has been designed for transverse size and profile measurement on both the electron beam and the FEL radiation. Challenging design constrains are present: COTR suppression, seed laser suppression, FEL wavelength range and minimization of the ionizing radiation delivered to the undulators. This paper describes the novel design and the obtained performance with the FERMI intra undulator screen system (IU-FEL).

WECC04	Analysis of the Electro-optical Front End for the New 40 GHz Bunch Arrival Time Monitor System	pick-up, electron, timing, FEL	571
	A. Kuhl, J. Rönsch-Schulenburg, J. Roßbach Uni HH, Hamburg, Germany A. Angelovski, R. Jakoby, A. Penirschke TU Darmstadt, Darmstadt, Germany M. Bousonville, M.K. Czwalinna, H. Schlarb, C. Sydlo DESY, Hamburg, Germany S. Schnepp IFH, Zurich, Switzerland T. Weiland TEMF, TU Darmstadt, Darmstadt, Germany
	The Free electron LASer in Hamburg (FLASH) is currently equipped with four Bunch Arrival time Monitors (BAMs) which achieve a time resolution of less than 10 fs for bunch charges higher than 500 pC (1). In order to achieve single spike FEL pulses at FLASH, electron bunch charges down to 20 pC are of interest. With the current BAMs the required time resolution is not reachable for bunch charges below 500 pC. Therefore new pickups with a bandwidth of up to 40 GHz (2) are designed and manufactured. The signal evaluation takes place with a time-stabilized reference laser pulse train which is modulated with an Electro-Optical intensity Modulator (EOM). The new pickup system also requires a new electro-optical frontend with a 40 GHz EOM. The theoretical limits of the time resolution depending on the RF signal at different bunch charges and on the jitter of the reference laser pulses where analyzed for the new EOM. (1) M. K. Bock et al. in Proceedings of DIPAC 2011, Hamburg, Germany,2011, p. 365 (2) A. Angelovski, A. Kuhl et al. in Proceedings of IPAC 2011, San Sebastian, Spain, 2011, p. 1177 and p. 1186
	Slides WECC04 [12.560 MB]

THCB01	Electron-Lens Test Stand Instrumentation Progress	gun, electron, instrumentation, cathode	602
	T.A. Miller, J.N. Aronson, D.M. Gassner, X. Gu, A.I. Pikin, P. Thieberger BNL, Upton, Long Island, New York, USA
	Funding: Work supported by B.S.A, LLC under contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. In preparation for installation of Electron Lenses into RHIC, planned for late 2012, a working test stand is in use testing the performance of the gun, collector, modulator, instrumentation and controls. While testing & operating the instrumentation, both progress and pitfalls were encountered. Results are presented from issues including ground loop signals generated by the DCCTs, static magnetic field interference, competing YAG screen illumination techniques, YAG crystal damage during beam operation, performance of the four quadrant beam scraper electrodes, and challenges in measuring beam current in conductors. Working knowledge and insight into each of these systems has been gained through difficulties leading to success. These insights are presented with supporting data and images.
	Slides THCB01 [32.453 MB]

Paper

Title

Other Keywords

Page

MOIA02

Progress of Beam Instumentation in J-PARC Linac

linac, proton, DTL, operation

1

A. Miura
JAEA/J-PARC, Tokai-mura, Japan

J-PARC, one of the high intensity proton accelerators, achieved the output power of 300 kW at the downstream rapid cycling synchrotron with a beam energy of 181 MeV and a beam current of 15 mA. When an upgrade of an ion source which can provide 50 mA and the installation of the additional acceleration cavities for the energy upgrade up to 400 MeV are completed, output power can reach 1MW. To meet with the requirements of the high intensity beam diagnostics, we prepare several measures against high intensity proton related issues. The following subjects have been reported among many subjects: development of strip-line type beam position monitors, beam current monitors, phase monitors and transverse profile monitors. And the subjects of the beam diagnostic for the energy upgraded linac including the longitudinal beam profile monitor and the developing laser based profile monitor will be mentioned. A big earthquake occurred on May 11, 2011. We successfully recovered to have commercial operation, but a partial recovery is still undergoing. Influence of the quake on the J-PARC linac is also mentioned.

Slides MOIA02 [2.133 MB]

MOCC03

The First Electron Bunch Measurement by means of DAST Organic EO Crystals

electron, FEL, real-time, operation

29

Y. Okayasu, S. Matsubara, T. Togashi
JASRI/SPring-8, Hyogo-ken, Japan
M. Aoyama
JAEA/Kansai, Kyoto, Japan
A. Iwasaki, S. Owada
The University of Tokyo, Tokyo, Japan
T. Matsukawa
RIKEN ASI, Sendai, Miyagi, Japan
H. Minamide
RIKEN Advanced Science Insititute, Sendai, Miyagi, Japan
K. Ogawa, T. Sato, H. Tomizawa
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
E. Takahashi
RIKEN, Saitama, Japan

Pilot user experiments via the seeded FEL have been demonstrated at the Prototype Test Accelerator (VUV-FEL), SPring-8 from July, 2012. A precise measurement of the electron bunch charge distribution (BCD) is crucial key to keep spatial and temporal overlaps between high-order harmonic (HH) laser pulses and electron bunches. R&D of the 3D-BCD monitor with a single-shot detection has been extensively promoted at SPring-8. The monitor adopts a spectral decoding based Electro-Optic (EO) sampling technique that is non-destructive and enables real-time reconstruction of the 3D-BCD with a temporal resolution of 30- to 40-fs (FWHM). So far, such EO sampling based BCD monitors have been developed by utilizing inorganic EO crystals such as ZnTe and their temporal resolutions are limited to ~130 fs (FWHM). As a part of this project, the first BCD measurement with an organic EO crystal DAST has been successfully demonstrated at the facility. Signal intensities, temporal resolutions and radiation related issues via both ZnTe and DAST are discussed.

Slides MOCC03 [3.912 MB]

MOPA17

Modular Logarithmic Amplifier Beam Position Monitor Readout System at the University of Hawai'i

electron, GUI, FEL, detector

90

B.T. Jacobson, M.R. Hadmack, J. Madey, P. Niknejadi
University of Hawaii, Honolulu, HI, USA

High brightness electron beams for inverse Compton backscatter photon sources driven by thermionic microwave guns require real-time position measurements in order to achieve the spatial and temporal coincidence necessary to ensure statistically measurable signals. True logarithmic amplifiers are more adequately suited to signal comparison than are σ-delta methods. A low-cost, modular and scalable readout and data acquisition system for strip-line beam position monitors utilizing the AD640 log-amp is being developed at University of Hawai'i MkV Linear Accelerator and Free Electron Laser Lab. Initial measurements and prototyping of the hardware is complete with commissioning and deployment of the system currently ongoing. We present the methodology and early results of this project.

MOPA20

Development of 3D EO-Sampling System for the Ultimate Temporal Resolution

FEL, electron, timing, feedback

98

K. Ogawa, H. Tomizawa
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
S. Matsubara, Y. Okayasu
JASRI/SPring-8, Hyogo, Japan

We have been developing three dimensional bunch charge distribution (3D-BCD) monitor for FEL seeded with high-order harmonic (HH) pulse. 3D-BCD is based on EO-sampling technique with multiple EO crystal detectors in the manner of spectral decoding. Using this 3D-EO sampling technique, the positioning and timing of electron bunch is obtained in real-time with non-destructive measurement. For obtaining the high temporal resolution, an octave broadband probe laser with linear chirp rate of 1 fs/nm is required. We are developing an EO-probe laser pulse with ~10 μJ pulse energy and the bandwidth over 300 nm (FWHM). For meet these bandwidth and pulse energy, this EO-probe pulse is using a supercontinuum generated by photonic crystal fiber (PCF) and amplified with optical parametric amplification (OPA). Especially, for amplification with maintaining octave bandwidth, non-collinear OPA (NOPA) using BBO crystal and a pump source with a wavelength of 450 nm are adopted. The EO-probe pulse energy of 10 μJ provides for high S/N ratio to each detector and the bandwidth of 300 nm with 300 fs pulse duration allows the measurement for the 30 fs electron bunch duration (FWHM).

MOPA43

RF Front end for High Bandwidth Bunch Arrival Time Monitors in Free-Electron Lasers at DESY

pick-up, simulation, operation, electron

157

A. Penirschke, A. Angelovski, M. Hansli, R. Jakoby
TU Darmstadt, Darmstadt, Germany
M. Bousonville, M.K. Czwalinna, H. Schlarb, C. Sydlo
DESY, Hamburg, Germany
A. Kuhl
Uni HH, Hamburg, Germany
S. Schnepp
IFH, Zurich, Switzerland
T. Weiland
TEMF, TU Darmstadt, Darmstadt, Germany

Funding: Funded by the Federal Ministry of Education and Research (BMBF): 05K10RDA "Weiterentwickung eines Ankunftszeitmonitors"
The Free-Electron Laser in Hamburg FLASH is equipped with Bunch Arrival-time Monitors (BAMs) that use an electro-optical detection scheme to modulate the intensity of the femtosecond laser pulse train with the pickup signals (*). The achieved resolution of the existing BAMs are less than 10 fs for bunch charges higher than 500 pC. For lower bunch charges the time resolution drops significantly. Increased demands for low bunch charge operation modes of 20 pC and less at FLASH II and the European X-ray Free-Electron Laser XFEL require an upgrade of the existing beam diagnostic equipment. High bandwidth BAMs with newly developed cone-shaped pickups (**) promise sub-10 fs time resolution for both, the high and low bunch charge operation mode. This paper addresses the RF signal path of the high bandwidth BAMs for FLASH II and XFEL. It comprises radiation resistant coaxial cables, combiners and limiters up to a frequency of 40 GHz from the pickup electrodes to the Electro-optical Mach-Zehnder type modulator (EOM). Detailed investigations of the signal path using measurements and simulations with AWR Microwave Office allows for a good prediction of the signal quality and shape at the EOM.
(*) F. Löhl et al., Phys. Rev. Lett. 104,144801 (2010)
(**) A. Angelovski et al. in Proceedings of the International Particle Accelerator Conference (IPAC2011), San Sebastian, Spain, 2011, p.1177

MOPA46

Realization and Measurements of Cone-shaped Pickups for Bunch Arrival-time Monitors for FLASH and XFEL

pick-up, simulation, electron, free-electron-laser

165

A. Angelovski, M. Hansli, R. Jakoby, A. Penirschke
TU Darmstadt, Darmstadt, Germany
M. Bousonville, M.K. Czwalinna, H. Schlarb, C. Sydlo
DESY, Hamburg, Germany
A. Kuhl
Uni HH, Hamburg, Germany
S. Schnepp
IFH, Zurich, Switzerland
T. Weiland
TEMF, TU Darmstadt, Darmstadt, Germany

Funding: Funded by the Federal Ministry of Education and Research (BMBF): 05K10RDA "Weiterentwickung eines Ankunftszeitmonitors"
At the Free Electron Laser FLASH at DESY, the installed Bunch Arrival-time Monitors (BAMs) use an electro-optical detection scheme for arrival-time measurements. The achieved time resolution is in the sub-10 fs range for bunch charges higher than 500 pC. The extension of FLASH II and the European X-ray Free Electron Laser Project (XFEL) foresees a low charge operation mode with bunch charge of 20 pC or less. The time resolution of the BAMs significantly drops as the bunch charge reduces (*). By expanding the bandwidth of the pickups one can increase the time resolution at low charges. In this paper, we present the characterization results of the manufactured cone-shaped pickups introduced in (**) with a bandwidth up to 40 GHz. The pickups mounted in a vacuum body exhibit four-fold rotational symmetry with respect to the beam pipe. Due to different beam pipe apertures for FLASH and XFEL, two bodies are manufactured. The rf properties of the mounted pickups in case of open and sealed body as well as the pickups separately are measured and compared to the simulation results obtained by CST STUDIO SUITE®.
(*)M. K. Bock et al. in Proceedings of DIPAC 2011, Hamburg, Germany, 2011, p.365
(**)A. Angelovski et al. in Proceedings of IPAC 2011, San Sebastian, Spain, 2011, p.1177

MOPA49

EO-sampling-based Temporal Overlap Control System for an HH Seeded FEL

FEL, electron, operation, timing

176

S. Matsubara
RIKEN/SPring-8, Hyogo, Japan
M. Aoyama
JAEA/Kansai, Kyoto, Japan
A. Iwasaki, S. Owada
The University of Tokyo, Tokyo, Japan
K. Ogawa, T. Sato, H. Tomizawa
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
Y. Okayasu, T. Togashi, T. Watanabe
JASRI/SPring-8, Hyogo-ken, Japan
E. Takahashi
RIKEN, Saitama, Japan

FELs have greatly interested for the short-wavelength region. However, their temporal profile and frequency spectra have shot-to-shot fluctuation by a SASE process. One of the promising approached for the problems is a seeded FEL scheme by using a full-coherent light source. The seeded FEL has been demonstrated in the EUV region by employ the high-order harmonics (HH) generation from an external laser source at the SCSS test-accelerator in the SPring-8. It is important for the HH-seeded FEL scheme to synchronize and overlap between the seeding laser pulse and the electron bunch. Their timing difference and laser spatial pointing is drifting. Therefore, a timing feedback and non-destructive monitor are necessary to operate seeded FEL continuously. We have constructed the timing monitor based on Electro-Optic (EO) sampling which is measure the timing difference the seeded laser pulse and the electron bunch simultaneously with the seeded FEL process. The probe laser pulse for the EO-sampling system is optically split from the common external HH laser driver for the seeded FEL. The EO-sampling system is able to use timing feedback for continual operation of the HH-seededFEL.

MOPB79

Design of a High-precision Fast Wire Scanner for the SPS at CERN

vacuum, operation, booster, acceleration

259

R. Veness, N. Chritin, B. Dehning, J. Emery, J.F. Herranz Alvarez, M. Koujili, S. Samuelsson, J.L. Sirvent Blasco
CERN, Geneva, Switzerland

Studies are going on of a new wire scanner concept. All moving parts are inside the beam vacuum and it is specified for use in all the machines across the CERN accelerator complex. Key components have been developed and tested. Work is now focussing on the installation of a prototype for test in the Super Proton Synchrotron (SPS) accelerator. This article presents the specification of the device and constraints on the design for integration in the different accelerators at CERN. The design issues of the mechanical components are discussed and optimisation work shown. Finally, the prototype design, integrating the several components into the vacuum tank is presented.

MOPB82

Bunch-Compressor Transverse Profile Monitors of the SwissFEL Injector Test Facility

electron, operation, vacuum, undulator

271

G.L. Orlandi, M. Aiba, S. Bettoni, B. Beutner, H. Brands, R. Ischebeck, P. Peier, E. Prat, T. Schietinger, V. Schlott, V.G. Thominet
PSI, Villigen PSI, Switzerland
C. Gerth
DESY, Hamburg, Germany

The 250 MeV SwissFEL Injector Test Facility (SITF) is the test bed of the future 5.7 GeV SwissFEL linac that will drive a coherent FEL light source in the wavelength range 7-0.7 and 0.7-0.1 nm. Aim of the SITF is to demonstrate the technical feasibility of producing and measuring 10 or 200pC electron bunches with normalized emittance down to 0.25 μm. A further goal is to demonstrate that the electron beam quality is preserved in the acceleration process, in the X-Band linearizer and the magnetic compression from about 10 ps down to 200 fs. The SITF movable magnetic bunch-compressor is equipped with several CCD/CMOS cameras for monitoring the beam transverse profile and determining the beam energy spread: a Ce:YAG screen and an OTR screen camera at the mid-point of the bunch compressor and a SR camera imaging in the visible the Synchrotron Radiation emitted by the electron beam crossing the third dipole. Results on the commissioning of such instrumentations, in particular in the low charge limit, and measurements of the beam energy spread vs. the compression factor will be presented.

TUCC04

Measurement of Nanometer Electron Beam Sizes with Laser Interference using IPBSM

optics, detector, alignment, photon

310

J.N. Yan, S. Komamiya, M. Oroku, T.S. Suehara, Y. Yamaguchi, T. Yamanaka
University of Tokyo, Tokyo, Japan
S. Araki, T. Okugi, T. Tauchi, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan
Y. Kamiya
ICEPP, Tokyo, Japan

At ATF2, the Local Chromaticity Correction focusing scheme is to be verified through realizing its design vertical e^- beam size (σy ) of 37 nm. The 'IPBSM', installed at ATF2's virtual IP, is the only existing beam size monitor capable of measuring σy < 100 nm, making it indispensable for ATF's goals and R&D at future LCs. This owes to a novel technique of colliding e^- beam against laser interference fringes. σy is derived from the modulation depth of resulting Compton photons, which is large for small σy. The measurable range from O(10) nm ~ a few μm, is controlled by switching between laser crossing angles θ = 174° , 30°, and 2° - 8° . In early 2011, measuring σy < 300 nm was hindered by an immense earthquake and heavy signal jitters. The ensuing recovery and upgrades stabilized the laser system and improved resolution to 5%. In spring 2012, we commissioned advanced crossing angle modes by consistently measuring σy ≥ 150 nm. Our goals for the autumn 2012 run is to stably measure σy < 50 nm. Major hardware upgrades during the summer aim at more reliable alignment and optimization of specialized functions to suppress bias factors.

Slides TUCC04 [10.535 MB]

TUPA43

First Operation of the Electro-optical Sampling Diagnostics of the FERMI@Elettra FEL

electron, FEL, alignment, vacuum

449

M. Veronese, A. Abrami, E. Allaria, M. Bossi, M.B. Danailov, M. Ferianis, L. Fröhlich, S. Grulja, M. Predonzani, F. Rossi, G. Scalamera, C. Spezzani, M. Trovò, M. Tudor
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

The FERMI@Elettra seeded FEL has demanding specifications in terms of longitudinal properties of the electron beam. Several diagnostics are installed along the linac. At the entrance of the FEL1 undulator chain an electro optical sampling (EOS) station based on the spatial encoding scheme is installed. The EOS provides both time jitter and longitudinal profile measurements in a non-destructive way. The layout of this system is described and the first operational measurement results obtained are reported. The paper includes also the capability of this diagnostics to perform the temporal coarse alignment of the seed laser to the electron beam. Finally a discussion on the future developments foreseen for this system is given.

TUPA44

Status of the LCLS Experiment Timing System

timing, experiment, electron, feedback

453

J.C. Frisch, C. Bostedt, R.N. Coffee, A.R. Fry, N. Hartmann, J. May, D.J. Nicholson, S. Schorb, S.R. Smith
SLAC, Menlo Park, California, USA

Funding: Work Supported by Department of Energy Contract DE AC03 76SF00515
X-ray / optical laser pump - probe experiments are used for a significant fraction of the scientific work performed at LCLS. The experimental laser systems are locked to the timing of the electron beam through a combination of RF and optical fiber based systems. The remaining ~100 femtosecond RMS jitter of the X-rays relative to the optical laser is measured shot-to-shot by both a RF timing detector, and by direct X-ray to optical cross-correlation, and the result is used to correct the experiment timing to 10s of femtoseconds. We present the present status of the system and plans for future upgrades.

TUPA47

Middle-infrared Prism Spectrometer for Single-shot Bunch Length Diagnostics at the LCLS

detector, optics, diagnostics, radiation

463

T.J. Maxwell, Y. Ding, A.S. Fisher, J.C. Frisch, H. Loos
SLAC, Menlo Park, California, USA
C. Behrens
DESY, Hamburg, Germany

Funding: Work supported in part by US Department of Energy contract number DE-AC02-76SF00515.
Modern high-brightness accelerators such as laser plasma wakefield and free-electron lasers continue the drive to ever-shorter bunches. At low-charge (< 20 pC), bunches as short as 10 fs are reported at the Linac Coherent Light Source (LCLS). Advanced time-resolved diagnostics approaching the fs-level have been proposed requiring the support of rf-deflectors, modern laser systems, or other complex systems. Though suffering from a loss of phase information, spectral diagnostics remain appealing by comparison as compact, low-cost systems suitable for deployment in beam dynamics studies and operations instrumentation. Progress in mid-IR imaging and detection of the corresponding micrometer-range power spectrum has led to the continuing development of a single-shot, 1.2 - 40 micrometer prism spectrometer for ultra-short bunch length monitoring. In this paper we report further analysis and experimental progress on the spectrometer installation at LCLS.

TUPB48

Beam Instrumentation for the COSY Electron Cooler

electron, gun, detector, controls

468

V. Kamerdzhiev, L.J. Mao, K. Reimers
FZJ, Jülich, Germany
E.A. Bekhtenev, V.N. Bocharov, M.I. Bryzgunov, A.V. Bubley, A.P. Denisov, G.V. Karpov, V.M. Panasyuk, V.V. Parkhomchuk, V.B. Reva
BINP SB RAS, Novosibirsk, Russia
J. Dietrich
HIM, Mainz, Germany

The report deals with beam instrumentation of the electron cooler for COSY storage ring. The electron cooler is an electrostatic accelerator designed for beam energy up to 2 MeV and electron current up to 3 A with recuperation. The electron beam is immersed in longitudinal magnetic field so the electron motion is strongly magnetized. The control electrode in the electron gun is composed of four electrically isolated sectors. Applying AC voltage to one sector allows tracing of motion of that particular part of the beam. The electron beam shape is registered with the combination of 4-sector electron gun and the BPMs. This method allows observing both dipole and quadruple (galloping) modes of electron beam oscillation. Compass probe for measuring and tuning the direction of magnetic field in the cooling section is described. A profile monitor based on a few small Faraday cups for measuring distribution of the electron beam is presented.

TUPB57

Extreme Light Infrastructure (ELI Beamlines) - Research and Technology with new Ultra-short Pulse Intense Laser driven Sources of Energetic Photons and Charged Particles

electron, proton, plasma, target

482

L. Pribyl, L. Juha, G. Korn, T. Levato, B. Rus, S. Ter-Avetisyan
Czech Republic Academy of Sciences, Institute of Physics, Prague, Czech Republic
D. Margarone
INFN/LNS, Catania, Italy
S. Sebban
LOA, Palaiseau, France

Funding: Czech Science Foundation (Project No. P205/11/1165), the Czech Republic's Ministry of Education, Youth and Sports to ELI-Beamlines (CZ.1.05/1.1.00/483/02.0061) and OPVK CZ.1.07/2.3.00/20.0087).
We will be giving an overview on the development of the 'ELI-Beamline facility', which will be a high-energy, repetition-rate laser pillar of the ELI (Extreme Light Infrastructure) project. It will be an international facility for both academic and applied research, slated to provide user capability since the beginning of 2016. The main purpose of the facility is the generation and applications of laser driven high-brightness X-ray sources and accelerated particles (electrons, protons and ions). The laser system will be delivering pulses with length ranging between 10 and 150 fs and will provide high-energy Petawatt and 10-PW peak powers. We will concentrate on the development of short photon wavelength (20 eV-100 keV) laser driven sources and their practical implementation. The sources are either based on direct interaction of the laser beam with a gaseous or solid target or will first accelerate electrons which then will interact with laser produced wigglers or directly injected into undulators. The main planned short pulse laser driven x-ray sources and their parameters will be presented together with requirements on the relevant beam detectors.

TUPB76

Intra Undulator Screen Diagnostics for the FERMI@Elettra FEL

FEL, electron, undulator, radiation

519

M. Veronese, A. Abrami, E. Allaria, M. Bossi, A. Bucconi, M. De Marco, M. Ferianis, L. Fröhlich, L. Giannessi, S. Grulja, R. Sauro, C. Spezzani, M. Tudor
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
T. Borden
FRIB, East Lansing, Michigan, USA
F. Cianciosi
ESRF, Grenoble, France

The FERMI@Elettra seeded FEL poses demanding requirements in terms of intra undulator diagnostics due to the short wavelength of its FEL radiation and to the coexistence of the electron and photon FEL beams. An advanced multi-beam screen system has equipped both FEL1 and FEL2. The system has been designed for transverse size and profile measurement on both the electron beam and the FEL radiation. Challenging design constrains are present: COTR suppression, seed laser suppression, FEL wavelength range and minimization of the ionizing radiation delivered to the undulators. This paper describes the novel design and the obtained performance with the FERMI intra undulator screen system (IU-FEL).

WECC04

Analysis of the Electro-optical Front End for the New 40 GHz Bunch Arrival Time Monitor System

pick-up, electron, timing, FEL

571

A. Kuhl, J. Rönsch-Schulenburg, J. Roßbach
Uni HH, Hamburg, Germany
A. Angelovski, R. Jakoby, A. Penirschke
TU Darmstadt, Darmstadt, Germany
M. Bousonville, M.K. Czwalinna, H. Schlarb, C. Sydlo
DESY, Hamburg, Germany
S. Schnepp
IFH, Zurich, Switzerland
T. Weiland
TEMF, TU Darmstadt, Darmstadt, Germany

The Free electron LASer in Hamburg (FLASH) is currently equipped with four Bunch Arrival time Monitors (BAMs) which achieve a time resolution of less than 10 fs for bunch charges higher than 500 pC (1). In order to achieve single spike FEL pulses at FLASH, electron bunch charges down to 20 pC are of interest. With the current BAMs the required time resolution is not reachable for bunch charges below 500 pC. Therefore new pickups with a bandwidth of up to 40 GHz (2) are designed and manufactured. The signal evaluation takes place with a time-stabilized reference laser pulse train which is modulated with an Electro-Optical intensity Modulator (EOM). The new pickup system also requires a new electro-optical frontend with a 40 GHz EOM. The theoretical limits of the time resolution depending on the RF signal at different bunch charges and on the jitter of the reference laser pulses where analyzed for the new EOM.
(1) M. K. Bock et al. in Proceedings of DIPAC 2011, Hamburg, Germany,2011, p. 365
(2) A. Angelovski, A. Kuhl et al. in Proceedings of IPAC 2011, San Sebastian, Spain, 2011, p. 1177 and p. 1186

Slides WECC04 [12.560 MB]

THCB01

Electron-Lens Test Stand Instrumentation Progress

gun, electron, instrumentation, cathode

602

T.A. Miller, J.N. Aronson, D.M. Gassner, X. Gu, A.I. Pikin, P. Thieberger
BNL, Upton, Long Island, New York, USA

Funding: Work supported by B.S.A, LLC under contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
In preparation for installation of Electron Lenses into RHIC, planned for late 2012, a working test stand is in use testing the performance of the gun, collector, modulator, instrumentation and controls. While testing & operating the instrumentation, both progress and pitfalls were encountered. Results are presented from issues including ground loop signals generated by the DCCTs, static magnetic field interference, competing YAG screen illumination techniques, YAG crystal damage during beam operation, performance of the four quadrant beam scraper electrodes, and challenges in measuring beam current in conductors. Working knowledge and insight into each of these systems has been gained through difficulties leading to success. These insights are presented with supporting data and images.

Slides THCB01 [32.453 MB]