TY  - CONF
AU  - Kuriki, M.
AU  - Hayano, H.
AU  - Jin, X.J.
AU  - Kashiwagi, S.
AU  - Konomi, T.
AU  - Piot, P.
AU  - Power, J.G.
AU  - Sakaue, K.
AU  - Seimiya, Y.
AU  - Tamura, R.
AU  - Washio, M.
AU  - Yamamoto, N.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Effect of Initial Parameters on the Super Flat Beam Generation with the Phase-Space Rotation for Linear Colliders
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Linear collider is a concept to realize e⁺e⁻ collision beyond the limitation of the ring colliders by the synchrotron radiation. To obtain an enough luminosity, eg. 1.0·10⁺³⁴ cm⁻²sec⁻¹, the beam is focused down to nano-meter size with a high aspect ratio. This super flat beam is useful to improve the luminosity and to compensate the beam-beam effect, eg. Beamstrahlung. In a conventional design, the super-flat beam is produced by radiation damping in a storage ring. We propose to produce this super-flat beam with phase-space rotation techniques. We employ both Round to Flat Beam Transformation and Transverse to Longitudinal Emittance eXchange, the super flat beam can be generated by controlling the space-charge effect which spoiled the performance. We present the RFBT performance with respect to the initial conditions, i.e. beam size, initial emittance, solenoid field (strength and profile), etc.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 442
EP  - 444
KW  - emittance
KW  - simulation
KW  - gun
KW  - collider
KW  - solenoid
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-MOPMP009
UR  - http://jacow.org/ipac2019/papers/mopmp009.pdf
ER  - 

TY  - CONF
AU  - Shao, J.H.
AU  - Chen, H.B.
AU  - Conde, M.E.
AU  - Doran, D.S.
AU  - Ha, G.
AU  - Jing, C.-J.
AU  - Liu, W.
AU  - Peng, M.M.
AU  - Power, J.G.
AU  - Seok, J.
AU  - Shi, J.
AU  - Whiteford, C.
AU  - Wisniewski, E.E.
AU  - Zha, H.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Generation of High Power Short Rf Pulses using an X-Band Metallic Power Extractor Driven by High Charge Multi-Bunch Train
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Short pulse two-beam acceleration (TBA) is a structure wakefield acceleration (SWFA) approach aiming to achieve gradient above 250 MV/m using rf pulses less than 20 ns. An X-band 11.7 GHz metallic power extractor has been developed as the power source to test accelerating structures in this extreme regime. The power extractor is designed to be driven by high charge bunches separated by 769.2 ps (9 times the X-band period) on an L-band 1.3 GHz beamline. In the recent experiment, ~280 MW rf pulses with 3 ns flat-top have been measured by a coaxial rf pickup when driven by 8-bunch trains with a total charge of ~500 nC. The power level is ~50% lower than the theoretical prediction and simulation. Experimental investigation suggests that the missing power was mainly caused by the multipacting issue inside the rf pickup, which could be eliminated by a newly-designed directional coupler.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 734
EP  - 737
KW  - pick-up
KW  - experiment
KW  - multipactoring
KW  - acceleration
KW  - simulation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-MOPRB069
UR  - http://jacow.org/ipac2019/papers/moprb069.pdf
ER  - 

TY  - CONF
AU  - Litvinenko, V.
AU  - Brutus, J.C.
AU  - Conde, M.E.
AU  - Jing, C.-J.
AU  - Jing, Y.C.
AU  - Kanareykin, A.
AU  - Pinayev, I.
AU  - Power, J.G.
AU  - Vafaei-Najafabadi, N.
AU  - Wang, G.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Proposal for a High Transformer Ratio CW Dielectric Accelerator
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Advanced CW accelerators are one of high priority directions identified by Advanced Accelerator Concepts Research Roadmap Workshop Report *. High transformer ratio of beam-driven accelerators is critically important for cost-effective FEL systems. We present a proposed experiment for demonstrating a high transformer ratio CW dielectric accelerator using operational SRF accelerator built for Coherent electron Cooling experiment. This accelerator operates with CW electron beam comprised of 78 kHz train of electron bunches. Electron bunches with controllable longitudinal and charge up to 10 nC per bunch are generated in 1.25 MV SRF photo-electron gun. This bunches are ballistically compressed to duration of 10-to-30 psec and accelerated to 15 MeV in SRF linac**. Such bunches would be excellent drivers of high-transformer ratio DWA accelerators. In this paper we present expected performance of proposed CW DWA accelerator.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 773
EP  - 776
KW  - electron
KW  - SRF
KW  - experiment
KW  - wakefield
KW  - operation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-MOPRB087
UR  - http://jacow.org/ipac2019/papers/moprb087.pdf
ER  - 

TY  - CONF
AU  - Lobach, I.
AU  - Halavanau, A.
AU  - Huang, Z.
AU  - Kim, K.
AU  - Lebedev, V.A.
AU  - Murokh, A.Y.
AU  - Nagaitsev, S.
AU  - Romanov, A.L.
AU  - Shaftan, T.V.
AU  - Stancari, G.
AU  - Valishev, A.
AU  - Yakimenko, V.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Study of Fluctuations in Undulator Radiation in the IOTA Ring at Fermilab
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - We study turn-by-turn fluctuations in the number of emitted photons in an undulator, installed in the IOTA electron storage ring at Fermilab with an InGaAs PIN photodiode and an integrating circuit. Our study was motivated by the previous experiment *. We propose a theoretical model for the experimental data from * and in our own experiment we attempted to verify the model in an independent and more systematic way. Moreover, these fluctuations are an interesting subject for a study by itself, since they act as a seed for SASE in FELs. We improve the precision of the measurements from * by subtracting the average signal amplitude using a comb filter with a one-turn IOTA delay, and by using a special algorithm for noise subtraction. We obtain a reasonable agreement between our theoretical model and experiment. Along with repeating the experiment from *, which was performed at a constant beam current, we also collect data for fluctuations in undulator light at different beam current values. Lastly, in our experiment we were able to see the transition from Poisson statistics to Super-Poisson statistics for undulator light, whereas in * only the latter statistics was observed.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 777
EP  - 780
KW  - experiment
KW  - undulator
KW  - electron
KW  - radiation
KW  - photon
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-MOPRB088
UR  - http://jacow.org/ipac2019/papers/moprb088.pdf
ER  - 

TY  - CONF
AU  - Sun, Y.
AU  - Belcher, K.
AU  - Dooling, J.C.
AU  - Goel, A.
AU  - Hillman, A.L.
AU  - Keane, R.T.
AU  - Pietryla, A.F.
AU  - Shang, H.
AU  - Zholents, A.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - APS LINAC Interleaving Operation
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Three s-band RF guns are installed at the front end of the Advanced Photon Source (APS) linac: two thermionic cathode guns (RG2 and RG1), and one Photo-Cathode Gun (PCG). During normal operations, RG2 provides electron beams for the storage ring to generate x-rays for APS users. The PCG generates high brightness electron beams that can be accelerated through the APS linac and transported into the Linac Extension Area (LEA) for advanced accelerator technology and beam physics experiments. The alternating acceleration of the RG2 and PCG beam in the linac is possible, as most of the time, RG2 beam is only needed for ~20 seconds every two minutes. This mode of interleaving operation of RG2 and PCG beams through the APS linac requires some modifications/additions to several systems of the linac, including RF, magnets, controls and Access Control Interlock System etc. In this paper we report our interleaving design and present the commissioning results of the two beam interleaving operation.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1161
EP  - 1163
KW  - linac
KW  - gun
KW  - operation
KW  - storage-ring
KW  - booster
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-MOPTS119
UR  - http://jacow.org/ipac2019/papers/mopts119.pdf
ER  - 

TY  - CONF
AU  - White, G.R.
AU  - Cobb, T.M.
AU  - Dalesio, L.R.
AU  - Davidsaver, M.A.
AU  - Hartman, S.M.
AU  - Hickin, D.G.
AU  - Johnson, A.N.
AU  - Junkes, H.
AU  - Kasemir, K.-U.
AU  - Konrad, M.G.
AU  - Korhonen, T.
AU  - Kraimer, M.R.
AU  - Lange, R.
AU  - Pearson, M.R.
AU  - Rivers, M.L.
AU  - Sekoranja, M.
AU  - Shankar, M.V.
AU  - Shen, G.
AU  - Shroff, K.
AU  - Veseli, S.
AU  - Vodopivec, K.
AU  - Zimoch, D.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - The EPICS Software Framework Moves from Controls to Physics
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - The Experimental Physics and Industrial Control System (EPICS), is an open-source software framework for high-performance distributed control, and is at the heart of many of the world’s large accelerators and telescopes. Recently, EPICS has undergone a major revision, with the aim of better computing supporting for the next generation of machines and analytical tools. Many new data types, such as matrices, tables, images, and statistical descriptions, plus users’ own data types, now supplement the simple scalar and waveform types of the former EPICS. New computational architectures for scientific computing have been added for high-performance data processing services and pipelining. Python and Java bindings have enabled powerful new user interfaces. The result has been that controls are now being integrated with modelling and simulation, machine learning, enterprise databases, and experiment DAQs. We introduce this new EPICS (version 7) from the perspective of accelerator physics and review early adoption cases in accelerators around the world.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1216
EP  - 1218
KW  - EPICS
KW  - controls
KW  - detector
KW  - database
KW  - experiment
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUZZPLM3
UR  - http://jacow.org/ipac2019/papers/tuzzplm3.pdf
ER  - 

TY  - CONF
AU  - Ha, G.
AU  - Conde, M.E.
AU  - Power, J.G.
AU  - Shao, J.H.
AU  - Wisniewski, E.E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Tunable Bunch Train Generation Using Emittance Exchange Beamline With Transverse Wiggler
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Emittance exchange beamline provides a unique correlation between the upstream transverse momentum and downstream longitudinal timing. Similar to the bunch train generation concept using energy modulation and chicane, the emittance exchange beamline can convert the transverse momentum modulation to the temporal modulation at the end of the beamline. The beam can obtain this transverse modulation from alternating magnet array (e.g. 90 degree rotated undulator). While most of other methods provide only one knob to control both micro-bunch length and bunch-to-bunch spacing or hard to control one of the knobs, this method provides separated knobs for the micro-bunch length and spacing and they are easy to control. These knobs enable to separately control the fundamental frequency of the radiation and its bandwidth. We plan to demonstrate this method at Argonne Wakefield Accelerator facility (AWA). This poster present progress on this new method and its demonstration at AWA.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1612
EP  - 1614
KW  - wiggler
KW  - controls
KW  - simulation
KW  - emittance
KW  - bunching
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPGW089
UR  - http://jacow.org/ipac2019/papers/tupgw089.pdf
ER  - 

TY  - CONF
AU  - Sajaev, V.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Experimental Tests of the Automated APS-U Commissioning Algorithm at APS
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - APS Upgrade (APS-U) will feature hybrid seven-bend achromat lattice with very strong focusing elements and relatively small vacuum chamber aperture. Achieving design lattice parameters during commissioning will need to be accomplished quickly in order to minimize dark time for APS users. The paper will describe the automated start-to-end lattice commissioning algorithm starting with the first-turn trajectory correction and ending with the lattice correction. It will then show simulation results of the APS-U commissioning, and finally present results of the experimental tests of the commissioning at the existing APS.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1615
EP  - 1618
KW  - MMI
KW  - lattice
KW  - sextupole
KW  - simulation
KW  - closed-orbit
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPGW090
UR  - http://jacow.org/ipac2019/papers/tupgw090.pdf
ER  - 

TY  - CONF
AU  - Sajaev, V.
AU  - Yao, C.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Lattice Measurements of the APS Injector Rings
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - APS Upgrade will feature an entirely new storage ring but will keep the existing injector complex consisting of the linear accelerator, Particle Accumulator Ring (PAR) and Booster. Due to small dynamic aperture of the APS Upgrade lattice, swap-out injection is adapted when an entire old bunch is replaced with a new bunch. This injection requires Booster to provide high-charge bunches with up to 17 nC in a single bunch. An extensive work is being carried out on characterizing the existing injector rings to ensure future high-charge operation. In this paper, we will present results of the lattice measurement using the response matrix fit. We will show the analysis of the achievable lattice measurement accuracy in the APS Booster and describe fit parameter modifications required to achieve good fit accuracy for the PAR.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1619
EP  - 1622
KW  - quadrupole
KW  - emittance
KW  - booster
KW  - lattice
KW  - dipole
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPGW091
UR  - http://jacow.org/ipac2019/papers/tupgw091.pdf
ER  - 

TY  - CONF
AU  - Matsuba, S.
AU  - Fujimoto, M.
AU  - Hosaka, M.
AU  - Katoh, M.
AU  - Kawase, K.
AU  - Konomi, T.
AU  - Miyamoto, A.
AU  - Sasaki, S.
AU  - Yamamoto, N.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Experimental Demonstration of Vector Beam Generation With Tandem Helical Undulators
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Vector beam is a light beam with spatially modulated polarization state across the beam. Particular examples of vector beam are radial and azimuthal polarization which have donut-shaped intensity and radially and azimuthally oriented linear polarization state. Vector beam has long been interest in the laser community and it is well known that vector beam can be created by superposing two optical vortex beams which have spiral wave fronts. It has been demonstrated that optical vortex beam can be generated from a helical undulator as harmonics. Therefore, we propose a scheme to generate vector beam by superposing two optical vortex beams from two helical undulators in tandem, based on the principle of the ’crossed undulator’. The experiment was carried out at UVSOR BL1U. In this paper, we describe the principle and the experimental details.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1766
EP  - 1768
KW  - polarization
KW  - undulator
KW  - experiment
KW  - radiation
KW  - simulation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPRB037
UR  - http://jacow.org/ipac2019/papers/tuprb037.pdf
ER  - 

TY  - CONF
AU  - Kasa, M.
AU  - Anliker, E.R.
AU  - Ivanyushenkov, Y.
AU  - Shiroyanagi, Y.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - New Superconducting Undulator Magnetic Measurement System for the Advanced Photon Source Upgrade
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Magnetic measurements of existing superconducting undulators (SCUs) are performed under normal operating conditions after final assembly into the cryostat and before installation on the Advanced Photon Source (APS) storage ring. The SCU cryostat for the APS upgrade has been scaled in length from the current cryostat and will contain two SCUs. While some aspects of the current measurement system are desirable to retain, such as a room temperature measurement bore, scaling the current measurement techniques to the length required for the APS upgrade cryostat is not feasible. To address these challenges a unique system has been developed at the APS to allow measurements of the two SCU magnets in the long cryostat. The measurement system developed allows the magnets to be operated under normal operating conditions while maintaining the measurement equipment at room temperature and atmospheric pressure.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1881
EP  - 1883
KW  - GUI
KW  - undulator
KW  - photon
KW  - vacuum
KW  - storage-ring
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPRB094
UR  - http://jacow.org/ipac2019/papers/tuprb094.pdf
ER  - 

TY  - CONF
AU  - Kasa, M.
AU  - Anliker, E.R.
AU  - Fuerst, J.D.
AU  - Hasse, Q.B.
AU  - Ivanyushenkov, Y.
AU  - Kesgin, I.
AU  - Shiroyanagi, Y.
AU  - Trakhtenberg, E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Superconducting Undulators for the Advanced Photon Source Upgrade
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - The magnetic devices group at the Advanced Photon Source (APS) is in the process of designing and developing superconducting undulators (SCUs) for the APS upgrade. While similar in some aspects to previous SCU systems currently in operation at the existing APS, the new SCU systems will include two undulators installed in one cryostat which occupies an entire straight section of the storage ring. Straight sections containing planar undulators will either be configured as ’in-line’, where the two undulators behave as one source, or canted, where the two undulators are operated independently. Also under development is a superconducting arbitrary polarizing emitter (SCAPE) which can produce planar, elliptical, and helical undulator fields.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1884
EP  - 1886
KW  - undulator
KW  - vacuum
KW  - photon
KW  - electron
KW  - operation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPRB095
UR  - http://jacow.org/ipac2019/papers/tuprb095.pdf
ER  - 

TY  - CONF
AU  - Kim, K.-J.
AU  - Assoufid, L.
AU  - Decker, F.-J.
AU  - Huang, Z.
AU  - Lindberg, R.R.
AU  - Marcus, G.
AU  - Raubenheimer, T.O.
AU  - Shi, X.
AU  - Shu, D.
AU  - Shvyd'ko, Yu.
AU  - White, M.
AU  - Zhu, D.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Test of an X-ray Cavity using Double-Bunches from the LCLS Cu-Linac
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - We discuss a proposal to test the operation of an X-ray cavity consisting of Bragg reflectors. The test will con-stitute a major step demonstrating the feasibility of either an X-ray regenerative amplifier FEL or an X-ray FEL Oscillator. These cavity-based X-ray FELs will provide the full temporal coherence lacking in the SA-SE FELs. An X-ray cavity of rectangular path will be constructed around the first seven LCLS-II undulator units. The Cu-linac will produce a pair of electron bunches separated by the cavity-round-trip distance during each linac cycle. The X-ray pulse produced by the first bunch is deflected into the cavity and returns to the undulator where it is amplified due to the presence of the second bunch. The key challenges are: the preci-sion of the cavity mechanical construction, the quality of the diamond crystals, and the electron beam stability. When the LCLS-II super-conducting linac becomes available, the cavity can then be used for high-repetition rate studies of the X-ray RAFEL and XFELO concepts.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 1887
EP  - 1890
KW  - FEL
KW  - cavity
KW  - electron
KW  - laser
KW  - free-electron-laser
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPRB096
UR  - http://jacow.org/ipac2019/papers/tuprb096.pdf
ER  - 

TY  - CONF
AU  - Shao, J.H.
AU  - Baryshev, S.V.
AU  - Chen, G.
AU  - Conde, M.E.
AU  - Kovi, K.
AU  - Liu, W.
AU  - Power, J.G.
AU  - Schneider, M.S.
AU  - Spentzouris, L.K.
AU  - Wisniewski, E.E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Systematic Benchmarking of a Planar (N)UNCD Field Emission Cathode
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Planar nitrogen-incorporated ultrananocrystalline diamond, (N)UNCD, is a unique and attractive field emission source because of the capability to generate high charge beam, the simplicity of production without shaped emitters, and the ease of handling with moderate vacuum requirement. In the presented study using an L-band normal conducting single-cell rf gun, a (N)UNCD cathode has been conditioned to 42 MV/m with a well-controlled manner and reached a maximum charge of 15 nC and an average emission current of 6~mA during a 2.5 us emission period. The systematic study of emission properties during the rf conditioning process illustrates the tunability of (N)UNCD in a wide range of surface gradients. This research demonstrates the versatility of (N)UNCD cathode which could enable multiple designs of field emission rf injector for industrial and scientific applications.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 2083
EP  - 2086
KW  - cathode
KW  - gun
KW  - experiment
KW  - electron
KW  - ECR
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPTS070
UR  - http://jacow.org/ipac2019/papers/tupts070.pdf
ER  - 

TY  - CONF
AU  - Nichols, K.E.
AU  - Andrews, H.L.
AU  - Antipov, S.P.
AU  - Chen, G.
AU  - Conde, M.E.
AU  - Doran, D.S.
AU  - Ha, G.
AU  - Kim, D.
AU  - Liu, W.
AU  - Power, J.F.
AU  - Shao, J.H.
AU  - Simakov, E.I.
AU  - Whiteford, C.
AU  - Wisniewski, E.E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Experimental Results of Dense Array Diamond Field Emitters in RF Gun
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - We present experimental emission results from arrays of diamond field emitter tips operating in an RF gun at the Argonne Cathode Test-stand. Results from various arrays will be presented with different spacing between array elements. Very high charge densities were produced at various field gradients. The maximum field gradient for a particular geometry was discovered and break-down effects will be presented. Cathode lifetime was preliminarily studied. Further experiments are being planned and work on the cathode design optimization to produce higher quality beams will be discussed.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 2134
EP  - 2136
KW  - cathode
KW  - gun
KW  - experiment
KW  - solenoid
KW  - wakefield
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPTS090
UR  - http://jacow.org/ipac2019/papers/tupts090.pdf
ER  - 

TY  - CONF
AU  - Xu, T.
AU  - Jing, C.-J.
AU  - Kanareykin, A.
AU  - Piot, P.
AU  - Power, J.G.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Spatio-Temporal Shaping of the Photocathode Laser Pulse for Low-Emittance Shaped Electron Bunches
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Photocathode laser shaping techniques to generate temporally shaped electron bunches are appealing owing to their simplicity. Such technique is being considered to form shaped electron bunches to enhance the transformer ratio in beam-driven accelerators. At low energy (i.e. during the emission process) the transverse and longitudinal space charge effects are coupled so that attaining a low beam transverse emittance require the laser to be spatiotemporal shaped. In this paper, we explore the generation of a linearly-ramped bunch with optimized transverse emittance by temporally and radially shaping the laser pulse to provide an adequate initial distribution. We discuss a possible implementation of the optical shaping technique and describe a planned experiment.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 2163
EP  - 2166
KW  - laser
KW  - electron
KW  - cathode
KW  - emittance
KW  - simulation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPTS104
UR  - http://jacow.org/ipac2019/papers/tupts104.pdf
ER  - 

TY  - CONF
AU  - Kutsaev, S.V.
AU  - Agustsson, R.B.
AU  - Berry, R.D.
AU  - Chao, D.
AU  - Conway, Z.A.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Stand-alone Accelerator System Based on SRF Quarter-wave Resonators
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Superconducting accelerators are large and complex systems requiring a central refrigerator and distributed transfer systems to supply 2-4 K liquid helium. Stand-alone, cryocooler-based systems are of interest both to scientific facilities and industrial applications, as they do not require large cryogenic infrastructure and trained specialists for operation. Here we present our approach to the challenge of using low-power commercially available cryocoolers to operate niobium superconducting resonators at 4.4 K with high accelerating voltages and several watts of heating. Engineering and design results from RadiaBeam Systems, collaborating with Argonne National Laboratory, for a stand-alone liquid-cooled cryomodule with 10 Watts of 4.4 K cooling capacity housing a 72.75 MHz quarter-wave resonator operating at 2 MV for synchronous ions travelling at 7.7% of speed of light will be discussed.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 2185
EP  - 2188
KW  - cryomodule
KW  - SRF
KW  - operation
KW  - cavity
KW  - vacuum
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPTS112
UR  - http://jacow.org/ipac2019/papers/tupts112.pdf
ER  - 

TY  - CONF
AU  - Kutsaev, S.V.
AU  - Agustsson, R.B.
AU  - Berry, R.D.
AU  - Borland, M.
AU  - Chao, D.
AU  - Chimalpopoca, O.
AU  - Nassiri, A.
AU  - Smirnov, A.Yu.
AU  - Sun, Y.
AU  - Taletski, K.V.
AU  - Verma, A.
AU  - Waldschmidt, G.J.
AU  - Zholents, A.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Microwave Thermionic Electron Gun for Synchrotron Light Sources
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Thermionic RF guns are the source of electrons used in many practical applications, such as drivers for synchrotron light sources, preferred for their compactness and efficiency. RadiaBeam Technologies has developed a new thermionic RF gun for the Advanced Photon Source at Argonne National Laboratory, which would offer substantial improvements in reliable operations with a robust interface between the thermionic cathode and the cavity, as well as better RF performance, compared to existing models. This improvement became possible by incorporating new pi-mode electromagnetic design, robust cavity back plate design, and a cooling system that will allow stable operation for up to 1 A of beam current and 100 Hz rep rate at 1.5 μs RF pulse length, and 70 MV/m peak on-axis field in the cavity. In this paper, we discuss the electromagnetic and engineering design of the cavity and provide the test results of the new gun.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 2189
EP  - 2192
KW  - gun
KW  - cathode
KW  - electron
KW  - cavity
KW  - coupling
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-TUPTS113
UR  - http://jacow.org/ipac2019/papers/tupts113.pdf
ER  - 

TY  - CONF
AU  - Tan, W.H.
AU  - Piot, P.
AU  - Zholents, A.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Longitudinal-Phase-Space Manipulation for Efficient Beam-Driven Structure Wakefield Acceleration
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Collinear beam-driven structure wakefield acceleration (SWFA) is an advanced acceleration technique that could support the compact generation of high-energy beams for future multi-user x-ray free-electron-laser facilities*. Producing an ideal shaped drive beam through phase space manipulation is crucial for an efficient SWFA. Controlling the final longitudinal-phase space of the drive beam necessitate staged beam manipulations during acceleration. This paper describes the preliminary design of an accelerator beamline capable of producing drive beam with tailored current distribution and longitudinal-phase-space correlation. The proposed design is based on simple analytical models combined in a 1-D longitudinal beam-dynamics simulation tracking program supporting forward and backward (time reversal) tracking.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 2296
EP  - 2299
KW  - wakefield
KW  - linac
KW  - electron
KW  - simulation
KW  - acceleration
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-WEZZPLS3
UR  - http://jacow.org/ipac2019/papers/wezzpls3.pdf
ER  - 

TY  - CONF
AU  - Antipov, S.P.
AU  - Avrakhov, P.V.
AU  - Ha, G.
AU  - Kuzikov, S.V.
AU  - Liu, A.
AU  - Power, J.G.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Ultra-High Gradient Short RF Pulse Gun
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - High brightness beams enable novel applications like x-ray free electron lasers and ultrafast electron microscopes. High brightness beams essentially consist of a large number of electrons in a small phase space volume, i.e. a high peak current. When such beams are generated from the cathode, there is a strong space charge force, which elongates the bunch and reduces its brightness. An optimal solution is to raise the accelerating voltage in the gun. However, the maximum gradient is limited by the effects of RF breakdown. The probability of RF breakdown is reduced as the RF pulse length decreases. We present a development of an electron photoinjector operating with short RF pulse, 10 ns scale. We have designed an X-band gun including the RF design, beam quality optimization, and engineering. The gun will be fed by 10 ns, 300 MW RF pulse generated at the Argonne Wakefield Accelerator Facility for two-beam acceleration experiments. We also manufactured an aluminum prototype and measured its microwave properties, most importantly, fill time. The proposed high brightness beam source can be used as the main beam in wakefield accelerators. It will find commercial applications in ultrafast electron diffraction and microscopy systems.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 2987
EP  - 2989
KW  - gun
KW  - electron
KW  - cathode
KW  - emittance
KW  - brightness
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-WEPRB072
UR  - http://jacow.org/ipac2019/papers/weprb072.pdf
ER  - 

TY  - CONF
AU  - Seok, J.
AU  - Chung, M.
AU  - Conde, M.E.
AU  - Ha, G.
AU  - Power, J.G.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Suppression of Correlated Energy Spread Using Emittance Exchange
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - An emittance exchange (EEX) provides a precise longitudinal phase space manipulation of electron bunch. It has been studied for an easy and precise control of temporal distribution, but controls of energy distribution have not been explored. Since the energy control using EEX is under the identical principle to the temporal control, the EEX beamline can control a correlated energy spread of the electron bunch. This would benefit accelerator facilities requiring a low energy spread such as X-ray Free Electron Laser Oscil-lator (XFELO). In this paper, we present principle and preliminary simulation work on the suppression of correlated energy spread using the EEX beamline. ing the EEX beamline.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3275
EP  - 3278
KW  - cavity
KW  - linac
KW  - controls
KW  - simulation
KW  - electron
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-WEPTS066
UR  - http://jacow.org/ipac2019/papers/wepts066.pdf
ER  - 

TY  - CONF
AU  - Xu, T.
AU  - Conde, M.E.
AU  - Ha, G.
AU  - Kuriki, M.
AU  - Piot, P.
AU  - Power, J.G.
AU  - Wisniewski, E.E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Generation High-Charge of Flat Beams at the Argonne Wakefield Accelerator
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Beams with large transverse emittance ratios (flat beams)have received renewed interest for their possible applications in future linear colliders and advanced accelerators. A flat beam can be produced by generating a magnetized beam and then repartitioning its emittance using three skew quadrupoles. In this paper, we report on the experimental generation of∼1nC flat beams at the Argonne WakefieldAccelerator (AWA). The emittance ratio of the flat beam is demonstrated to be continuously variable by adjusting the magnetic field on the cathode.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3337
EP  - 3340
KW  - emittance
KW  - solenoid
KW  - electron
KW  - quadrupole
KW  - experiment
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-WEPTS094
UR  - http://jacow.org/ipac2019/papers/wepts094.pdf
ER  - 

TY  - CONF
AU  - Harkay, K.C.
AU  - Abid, I.A.
AU  - Berenc, T.G.
AU  - Berg, W.
AU  - Blednykh, A.
AU  - Borland, M.
AU  - Brill, A.R.
AU  - Bromberek, D.J.
AU  - Byrd, J.M.
AU  - Calvey, J.R.
AU  - Carvelli, J.
AU  - Dooling, J.C.
AU  - Emery, L.
AU  - Fors, T.
AU  - Fystro, G.I.
AU  - Goel, A.
AU  - Hui, D.
AU  - Keane, R.T.
AU  - Laird, R.
AU  - Lenkszus, F.
AU  - Lindberg, R.R.
AU  - Lumpkin, A.H.
AU  - Madden, T.J.
AU  - Micklich, B.J.
AU  - Morrison, L.H.
AU  - Pasky, S.J.
AU  - Sajaev, V.
AU  - Sereno, N.
AU  - Shang, H.
AU  - Smith, T.L.
AU  - Stevens, J.B.
AU  - Sun, Y.
AU  - Waldschmidt, G.J.
AU  - Wang, J.
AU  - Wienands, U.
AU  - Wootton, K.P.
AU  - Xiao, A.
AU  - Yang, B.X.
AU  - Yang, Y.
AU  - Yao, C.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - High-Charge Injector for on-Axis Injection Into A High-Performance Storage Ring Light Source
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Next-generation, high-performance storage ring light sources based on multibend achromat optics will require on-axis injection because of the extremely small dynamic aperture. Injectors will need to supply full-current bunch replacement in the ring with high single-bunch charge for swap-out. For upgrades of existing light sources, such as the Advanced Photon Source Upgrade (APS-U), it is economical to retain the existing injector infrastructure and make appropriate improvements. The challenges to these improvements include achieving high single-bunch charge in the presence of instabilities, beam loading, charge stability and reliability. In this paper, we discuss the rationale for the injector upgrades chosen for APS-U, as well as backup and potential alternate schemes. To date, we have achieved single-bunch charge from the injectors that doubles the original design value, and have a goal to achieve about three times the original design value.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3423
EP  - 3426
KW  - booster
KW  - injection
KW  - synchrotron
KW  - storage-ring
KW  - emittance
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THYYPLM3
UR  - http://jacow.org/ipac2019/papers/thyyplm3.pdf
ER  - 

TY  - CONF
AU  - Andonian, G.
AU  - Bruhwiler, D.L.
AU  - Campese, T.J.
AU  - Conde, M.E.
AU  - Cook, N.M.
AU  - Doran, D.S.
AU  - Ha, G.
AU  - O'Shea, F.H.
AU  - Power, J.G.
AU  - Rosenzweig, J.B.
AU  - Shao, J.H.
AU  - Wisniewski, E.E.
AU  - Xu, T.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Status on a Laser Injection in Beam Driven Dielectric Wakefield Accelerator Experiment
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - The generation of high-brightness beams with ultra-low emittance using the plasma photocathode technique has gained significant traction in recent years. The practical execution of a combined plasma wakefield acceleration section and a laser injected typically requires a dual gas medium for precision ionization of low and high ionization thresholds. The concept can be partially simplified in experiment by replacing the plasma wakefield acceleration component with a dielectric wakefield acceleration scheme, sacrificing field gradient but maintaining low emittance beam generation. In this paper, we describe the progress on the design of a hybrid scheme, using laser injection in a gas medium within a dielectric wakefield accelerator structure. The proof-of-concept experiment is planned to take place at the Argonne Wakefield Accelerator.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3761
EP  - 3763
KW  - wakefield
KW  - experiment
KW  - plasma
KW  - laser
KW  - electron
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THPGW073
UR  - http://jacow.org/ipac2019/papers/thpgw073.pdf
ER  - 

TY  - CONF
AU  - Roussel, R.J.
AU  - Andonian, G.
AU  - Conde, M.E.
AU  - Doran, D.S.
AU  - Ha, G.
AU  - Lynn, W.J.
AU  - Power, J.G.
AU  - Rosenzweig, J.B.
AU  - Seok, J.
AU  - Whiteford, C.
AU  - Wisniewski, E.E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Transformer Ratio Measurements from Ramped Beams in the Plasma Blowout Regime using Emittance Exchange
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - We present initial measurements from a UCLA-Argonne Wakefield Accelerator collaborative plasma wakefield acceleration (PWFA) experiment aimed at demonstrating the dependence of transformer ratio on longitudinal beam shape. The transformer ratio or the ratio between the maximum acceleration of the witness and the maximum deceleration of the drive beam, is key to a mature, beam-based, plasma wakefield accelerator design. Utilizing the unique capabilities of the emittance exchange (EEX) beamline, we may obtain transformer ratios in excess of six in PWFA. We present the experimental beamline design, relevant beam diagnostics and explore preservation of the longitudinal beam profile.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3778
EP  - 3781
KW  - plasma
KW  - wakefield
KW  - emittance
KW  - experiment
KW  - acceleration
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THPGW088
UR  - http://jacow.org/ipac2019/papers/thpgw088.pdf
ER  - 

TY  - CONF
AU  - Shu, D.
AU  - Anton, J.W.J.
AU  - Kang, H.-S.
AU  - Kearney, S.P.
AU  - Kim, K.
AU  - Min, C.-K.
AU  - Oh, B.G.
AU  - Rah, S.Y.
AU  - Shvyd'ko, Yu.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Mechanical Design of a Diamond Crystal Hard X-Ray Self-Seeding Monochromator for PAL-XFEL
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - As a part of the Argonne Strategic Partnership Project (SPP) 85H21, a collaboration between Advanced Photon Source (APS), Argonne National Laboratory (ANL) and Pohang Accelerator Laboratory (PAL), we have designed, constructed, and tested a thin-film-diamond monochromator for the PAL X-ray Free-Electron-Laser (PAL-XFEL) hard x-ray self-seeding project*. The mechanical design of the PAL-XFEL diamond crystal hard x-ray self-seeding monochromator is based on the APS design of a diamond-crystal monochromator for the LCLS hard x-ray self-seeding project** with enhanced diamond crystal holder for two thin-film-diamond crystals with thicknesses of 30 microns and 100 microns***. The customized high quality thin-film-diamonds and special graphite holder were provided by the Technological Institute for Super-hard and Novel Carbon Materials of Russia (TISNCM)****, and tested at the APS***. An in-vacuum multi-axis precision positioning mechanism is designed to manipulate the duo-thin-film diamonds holder with resolutions and stabilities required by the hard x-ray self-seeding physics. Mechanical specifications, designs, and preliminary test results of the diamond monochromator are presented in this paper.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3782
EP  - 3785
KW  - FEL
KW  - vacuum
KW  - controls
KW  - alignment
KW  - electron
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THPGW089
UR  - http://jacow.org/ipac2019/papers/thpgw089.pdf
ER  - 

TY  - CONF
AU  - Liu, W.
AU  - Conde, M.E.
AU  - Doran, D.S.
AU  - Ha, G.
AU  - Power, J.G.
AU  - Shao, J.H.
AU  - Whiteford, C.
AU  - Wisniewski, E.E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - A Novel Design of a Laser Phase Monitor for AWA RF Photocathode Electron Gun
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - It is critical to maintain a stable laser phase for RF photocathode electron gun to achieve high beam stability. In order to achieve a higher beam stability for AWA(Argonne Wakefield Accelerator) beamline, a novel laser phase monitor has been designed to allow us to monitor and feedback on. Both the design and its applications at AWA are presented in this paper.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 4076
EP  - 4077
KW  - laser
KW  - LLRF
KW  - electron
KW  - feedback
KW  - controls
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THPRB107
UR  - http://jacow.org/ipac2019/papers/thprb107.pdf
ER  - 

TY  - CONF
AU  - Dooling, J.C.
AU  - Dejus, R.J.
AU  - Sajaev, V.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Synchrotron Radiation Heating of the Helical Superconducting Undulator
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - A helical superconducting undulator (HSCU) was installed in the Advanced Photon Source (APS) Storage Ring (SR) during the January 2018 maintenance period. Shortly after the reintroduction of beam into the SR in late January, higher than expected heating was observed in the cryogenic cooling system. Steering the electron beam orbit in the upstream dipole provided reduction of the amount of synchrotron radiation reaching into the HSCU and allowed the device to properly cool and operate. Modeling the HSCU geometry with MARS shows the importance of Compton Scattering in transferring synchrotron photons with energies in the range of 10-100 keV through the vacuum chamber into the HSCU magnet pole and winding regions. Simulations carried out using MARS with EGS5 enabled indicate a rapid increase in transfer efficiency from the chamber wall to the HSCU with photon energy. Realistic spectral distributions of synchrotron photons are employed as input to MARS for several bending magnet field strengths.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 4328
EP  - 4331
KW  - photon
KW  - vacuum
KW  - synchrotron
KW  - radiation
KW  - synchrotron-radiation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THPTS093
UR  - http://jacow.org/ipac2019/papers/thpts093.pdf
ER  - 

TY  - CONF
AU  - Samadi, N.
AU  - Chapman, L.D.
AU  - Dallin, L.O.
AU  - Shi, X.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Application of a Phase Space Beam Position and Size Monitor for Synchrotron Radiation
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - We will report on a system (ps-BPM) that can measure the electron source vertical position and angular motion along with the vertical source size and angular size at a single location in a synchrotron bend magnet beamline*. This system uses a combination of a monochromator and a filter with a K-edge to which the monochromator was tuned in energy. The vertical distribution of the beam with and without the filter was simultaneously visualized with an imaging detector. The small range of angles from the source onto the monochromator crystals creates an energy range that allows part of the beam to be below the K-edge and the other part above. Measurement of the beam vertical location without the absorber and edge vertical location with the absorber allowes measurement of the source position and angle. The beam width and edge width give information about the vertical electron source size and angular distribution. The ps-BPM measurements have been made where the electron beam size and angular distribution was adjusted using skew quads. The ps-BPM measurements correlate well with modeling of the ps-BPM system as well as conventional beam size measurements using a pinhole.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 4376
EP  - 4379
KW  - electron
KW  - synchrotron
KW  - detector
KW  - synchrotron-radiation
KW  - radiation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-FRXXPLS3
UR  - http://jacow.org/ipac2019/papers/frxxpls3.pdf
ER  -