IPAC2016 - List of Keywords (positron)

Paper	Title	Other Keywords	Page
MOPMB033	The Influence of Strip-line BPMs' Measuring Results Made by Edge of the Ultra-relativistic Electron Beam	simulation, electron, wakefield, linac	161
	S.Z. Wang, N. Gan, X. Huang IHEP, Beijing, People's Republic of China
	This paper describes the impact on the measuring results of the stripline beam position monitor (BPM) produced by the edge of the ultra-relativistic electron beam when we take the transverse size of the beam into account. Simulations have been made by using the Wakefield Solver of CST Particle Studio. And the result of this influence at different ratio of beam horizontal width σ and the BPM inner diameter a has been obtained. This kind of influence has been observed in the stripline BPMs in the transfer line of Beijing Positron Electron Colliders upgraded version II (BEPCII). The research is useful when we design the inner diameter of the stripline BPMs for ultra-relativistic electron beam, meanwhile it provides reference to distinguish the invalid ones from the measuring results obtained by the stripline BPMs in the ultra-relativistic situation.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB033
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB046	Design and Calculation Error Analysis of a High Order Mode Cavity Bunch Length Monitor	cavity, simulation, linac, electron	196
	J.G. Guo, Q. Luo, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: National Science Foundation of China (11375178) and Fundamental Research Funds for the Central Universities (WK2310000046). A two-cavity bunch length monitor for linac of positron source is designed. Fifth harmonic cavity resonates at 14.28 GHz (fifth harmonic of the linac fundamental frequency 2.856 GHz) with mode TM020, as this mode could provide larger cavity radius. Each cavity equipped with a filter to suppress unwanted signal. An improved bunch length calculation method was proposed. A simulation was conducted in CST Particle Studio for beam current from 100-300 mA, bunch length from 5-10 ps. Bunch length was calculated and compared by these two methods
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB046
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR013	Development, Calibration and Application of New-generation Dissectors with Picosecond Temporal Resolution	electron, laser, radiation, operation	251
	O.I. Meshkov, O. Anchugov, V.L. Dorohov, G.Y. Kurkin, A.V. Petrozhitskii, D.A. Shvedov, E.I. Zinin BINP SB RAS, Novosibirsk, Russia P.B. Gornostaev, M.Ya. Schelev, E.V. Shashkov, A. V. Smirnov, A.I. Zarovskii GPI, Moscow, Russia
	Funding: The presented experimental results were implemented due to financial support of the Russian Science Foundation (Projects N 14-29-00295) A dissector is an electron-optical device designed for measurement of periodic light pulses of subnanosecond and picosecond duration. LI-602 dissector developed at BINP is widely used for routine measurements of a longitudinal profile of electron and positron beams at BINP electron-positron colliders and other similar installations]. This dissector is a part of many optical diagnostic systems and provides temporal resolution of about 20 ps. Recently* a new generation of picosecond dissectors were created on the basis of the PIF-01/S1 picosecond streak-image tube designed and manufactured at the General Physics Institute Photoelectronics Department (Moscow). The device has demonstrated a temporal resolution of 3-4 ps (FWHM). The procedure of temporal resolution calibration and results of application of the new-generation picosecond dissector are given in this work. *E.I. Zinin, O.I. Meshkov. JINST, 2015 1748-0221 10 P10024 doi:10.1088/1748-0221/10/10/P10024
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR013
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR052	Single-shot Bunch-by-Bunch Horizontal Beam Size Measurements using a Gated Camera at CesrTA	electron, ion, vacuum, synchrotron-radiation	364
	S. Wang Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA R. Holtzapple CalPoly, San Luis Obispo, California, USA
	Funding: Work supported by NSF NSF PHY-1416318, PHYS-1068662, PHYS-1535696 A visible-light beam size monitor has been built and commissioned to measure transverse beam profiles at CESR-TA. In order to eliminate beam jitter and to study bunch-by-bunch beam dynamics, a fast-gating camera has been utilized to measure single bunch transverse beam profiles. The minimum camera gate width is ~ 3ns which allows us to resolve single bunch beam dynamics along a CesrTA bunch train. Using single bunch interferometry at different bunch currents, we found that the horizontal beam sizes measured by gated camera are consistently less than those measured by a conventional CCD camera, demonstrating the elimination of turn-by-turn beam jitter with single shot capability. By stepping the camera trigger delay, we collected transverse beam profile images from each bunch in a 14ns-spacing 30-bunch train. The horizontal motion of each bunch as well as the horizontal beam size increases dramatically along an electron train but not along positron bunch trains under the same machine condition. The difference in single bunch horizontal dynamics may be a signature for the difference between electron cloud build-up for positron bunch trains versus ions present for electron bunch trains. S.T. Wang, D.L. Rubin, J. Conway, M. Palmer, D. Hartill, R. Campbell, R. Holtzapple, NIMA, 703 (2013) 80
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR052
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOBB02	FACET-II Accelerator Research with Beams of Extreme Intensities	electron, linac, plasma, damping	1067
	V. Yakimenko, Y. Cai, C.I. Clarke, S.Z. Green, C. Hast, M.J. Hogan, N. Lipkowitz, N. Phinney, G.R. White, G. Yocky SLAC, Menlo Park, California, USA
	In 2016, the second phase of SLAC's x-ray laser, the LCLS-II, will begin to use part of the tunnel occupied by FACET, and the world's only multi-GeV facility for advanced accelerator research will cease operation. FACET-II is a new test facility to provide DOE with the unique capability to develop advanced acceleration and coherent radiation techniques with high-energy electron and positron beams. FACET-II is an opportunity to build on the decades-long experience developed conducting advanced accelerator R&D at the FFTB and FACET and re-deploy HEP infrastructure in continued service of its mission. FACET-II provides a major upgrade over current FACET capabilities and the breadth of the potential research program makes it truly unique. It will synergistically pursue accelerator science that is vital to the future of both advanced acceleration techniques for High Energy Physics, ultra-high brightness beams for Basic Energy Science, and novel radiation sources for a wide variety of applications. The presentation will discuss FACET-II project status and plans for diverse experimental program.
	Slides TUOBB02 [17.664 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOBB02
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOCB01	First Commissioning of the SuperKEKB Vacuum System	vacuum, electron, photon, status	1086
	Y. Suetsugu, H. Hisamatsu, T. Ishibashi, K. Kanazawa, K. Shibata, M. Shirai, S. Terui KEK, Ibaraki, Japan
	The SuperKEKB, an electron-positron collider with asymmetric energies in KEK, has started the first commissioning with beams this year. One of major tasks in the commissioning is the beam scrubbing of new beam pipes in order to increase the beam lifetime and to decrease the background noise of the particle detector in the coming physics run. The temperatures and the vacuum pressures of new vacuum components, such as the bellows chambers, gate valves and the beam collimators, should be checked in this run. The decrease rate in the vacuum pressure are measured to estimate the vacuum scrubbing effect. Reported here will be the results obtained during the first commissioning and the present status of the vacuum system.
	Slides TUOCB01 [2.526 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOCB01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMB021	SLAC FACET-II Positron Damping Ring Magnet Design	lattice, damping, dipole, magnet-design	1154
	M.A.G. Johansson MAX IV Laboratory, Lund University, Lund, Sweden Y. Cai, V. Yakimenko SLAC, Menlo Park, California, USA
	The FACET-II facility, currently being designed at SLAC, will contain a small ~20 m circumference, 335 MeV, positron damping ring. The ring has to fit in the existing linac tunnel, meaning that a compact lattice with short distances between magnets is required. The detailed magnet design is done in Opera-3d, with a finite element model of a full damping ring arc being simulated. This article presents this magnet design in a relatively early stage, with iteration between magnet and lattice design currently in progress.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY001	Very Low Emittance Muon Beam using Positron Beam on Target	target, emittance, collider, electron	1536
	M. Antonelli, M.E. Biagini, M. Boscolo, A. Variola INFN/LNF, Frascati (Roma), Italy E. Bagli INFN-Ferrara, Ferrara, Italy G. Cavoto INFN-Roma, Roma, Italy P. Raimondi ESRF, Grenoble, France
	Muon beams are customarily obtained via K/π decays produced in proton interaction on target. In this paper we investigate the possibility to produce low emittance muon beams from electron-positron collisions at centre-of-mass energy just above the μ⁺{+}μ⁺{-} production threshold with maximal beam energy asymmetry, corresponding to a positron beam of about 45 GeV interacting on electrons on target. Performances on both amorphous and crystal target are presented, and the general scheme for the muon production will be given. We present the main features of this scheme with a first preliminary evaluation of the performances that could be achieved by a multi-TeV muon collider.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY001
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOR021	Incoherent Vertical Emittance Growth from Electron Cloud at CesrTA	simulation, dipole, electron, emittance	1707
	S. Poprocki, J.A. Crittenden, S.N. Hearth, J.D. Perrin, D. L. Rubin, S. Wang Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work supported by the US National Science Foundation PHY-1416318, PHY-0734867, and PHY-1002467, and the U.S. Department of Energy DE-FC02-08ER41538 We report on measurements of electron cloud (EC) induced tune shifts and emittance growth at the Cornell Electron-Positron Storage Ring Test Accelerator (CesrTA) with comparison to tracking simulation predictions. The simulations are based on a weak-strong model of the interaction of the positron beam (weak) with the electron cloud (strong), using electric fields computed with established EC buildup simulation codes (ECLOUD). Experiments were performed with 2.1 GeV positrons in a 30 bunch train with 14 ns bunch spacing and 9 mm bunch length, plus a witness bunch at varying distance from the train to probe the cloud as it decays. Measurements of the horizontal and vertical coherent tune shifts and horizontal and vertical bunch size were obtained for a range of train and witness bunch currents, and compared to simulations.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOW019	Preliminary Concept of Fast Positron Source Based on Photo-injector	electron, target, simulation, linac	1785
	Z. Chu, J.G. Guo, Q. Luo, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Supported by National Natural Science Foundation of China (11375178 and 11575181) and the Fundamental Research Funds for the Central Universities, Grant No WK2310000046 Based on the past experience in slow positron beam, researchers at NSRL/USTC proposed a fast positron source for detection of material deep tiny flaws. Different from conventional positron sources used in positron annihilation techniques, the planned positron source will be a positron production linac, similar to positron injectors used in colliders. To compress the positron pulse, the bombarding electron beam comes from a short bunch photo-injector. A computer simulation was performed using EGS4 and PARMELA code. The bombarding electron bunch is 300pC, with an energy of 30MeV. Simulations results showed that it is reasonable to expect a beam of more than 10⁵ positrons per pulse for future positron annihilation studies. Further work is to be done to achieve precise control of beam energy.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMW004	Progress in Detector Design and Installation for Measurements of Electron Cloud Trapping in Quadrupole Magnetic Fields at CesrTA	electron, quadrupole, detector, vacuum	2420
	J.A. Crittenden, S. Barrett, M.G. Billing, K.A. Jones, Y. Li, T.I. O'Connell, K. Olear, S. Poprocki, D. L. Rubin, J.P. Sikora Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work supported by the US National Science Foundation PHY-1416318, PHY-0734867, PHY-1002467, and the U.S. Department of Energy DE-FC02-08ER41538 Following up on our 2013 and 2014 measurements of electron cloud trapping in a quadrupole magnet with 7.4~T/m gradient in the 5.3~GeV positron storage ring at Cornell University, we have redesigned the shielded-stripline time-resolving electron detector and installed a wide-aperture quadrupole magnet at a location in the ring where its field can be compensated by a nearby quadrupole, thus allowing the first measurements of cloud trapping as a function of field gradient. The transverse acceptance of the electron detector has been tripled, allowing tests of model predictions indicating a dramatic cloud splitting effect which exhibits a threshold behavior as a function of bunch population. In addition, a vacuum chamber optimized for cloud buildup measurements using resonant microwave phenomena has been employed. We describe design considerations and modeling predictions for the upcoming 2016 data-taking run. This project is part of the CESR Test Accelerator program, which investigates performance limitations in low-emittance storage and damping rings.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW004
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPPA01	Demonstration of the Hollow Channel Plasma Wakefield Accelerator	plasma, laser, acceleration, wakefield	3202
	S.J. Gessner, J.M. Allen, C.I. Clarke, J.-P. Delahaye, J.T. Frederico, S.Z. Green, C. Hast, M.J. Hogan, N. Lipkowitz, M.D. Litos, B.D. O'Shea, D.R. Walz, V. Yakimenko, G. Yocky SLAC, Menlo Park, California, USA E. Adli, C.A. Lindstrøm University of Oslo, Oslo, Norway W. An, C.E. Clayton, C. Joshi, K.A. Marsh, W.B. Mori, N. Vafaei-Najafabadi UCLA, Los Angeles, California, USA S. Corde, A. Doche LOA, Palaiseau, France W. Lu TUB, Beijing, People's Republic of China
	Funding: Work supported by DOE contract DE-AC02-76SF00515. Over the past decade, there has been enormous progress in the field of beam and laser-driven plasma acceleration of electron beams. However, in order for plasma wakefield acceleration to be useful for a high-energy e⁺e^- collider, we need a technique for accelerating positrons in plasma as well. This is a unique challenge, because the plasma responds differently to electron and positron beams, with plasma electrons being pulled through the positron beam and creating a non-linear focusing force. Here, we demonstrate a technique called hollow channel acceleration that symmetrizes the wakefield response to beams of either charge. Using a transversely shaped laser pulse, we create an annular plasma with a fixed radius of 200 μm. We observe the acceleration of a positron bunch with energies up to 33.4 MeV in a 25 cm long channel, indicating an effective gradient greater than 100 MeV/m. This is the first demonstration of a technique that way be used for staged acceleration of positron beams in plasma.
	Slides THPPA01 [5.647 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPPA01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMB013	Proposal of 6 GeV Energy Recovery Linac Hybrid Machine	electron, linac, cavity, undulator	3254
	M. Shimada, K. Yokoya KEK, Ibaraki, Japan R. Hajima JAEA, Ibaraki-ken, Japan M. Tecimer University of Hawaii at Manoa, Honolulu, USA
	We proposed 6 GeV Energy Recovery Linac (ERL) as an intense gamma-ray source for the polarized positron source of International Linear Collider (ILC). In this scheme, Coherent Synchrotron Radiation from quasi-CW 6 GeV electron beam is stacked in optical cavity at middle infrared region, and it is used for inverse Compton scattering to generate 10 MeV polarized gamma-ray. The same 6 GeV superconducting linac accelerates both the electron and positron beams up to 5 GeV for injection to the dumping ring. Furthermore, it is available for X-ray light source by adding another recirculation loop. It can be expected as a diffraction limit light source at 10 keV, and the target of the brilliance is 10^22-23 ph/s/mm²/mrad²/b.w.0.1%. M. Shimada, Proceedings of IPAC'13
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB013
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR018	Comissioning of Upgraded VEPP-2000 Injection Chain	injection, electron, booster, linac	3811
	D.E. Berkaev, A.V. Andrianov, K.V. Astrelina, V.V. Balakin, A.M. Barnyakov, O.V. Belikov, M.F. Blinov, D.V. Bochek, D. Bolkhovityanov, F.A. Emanov, A.R. Frolov, K. Gorchakov, Ye.A. Gusev, A.S. Kasaev, E. Kenzhbulatov, I. Koop, I.E. Korenev, G.Y. Kurkin, N.N. Lebedev, A.E. Levichev, P.V. Logatchov, A.P. Lysenko, D.A. Nikiforov, V.P. Prosvetov, Yu. A. Rogovsky, S.L. Samoylov, A.I. Senchenko, P.Yu. Shatunov, Y.M. Shatunov, D.B. Shwartz, A.A. Starostenko, I.M. Zemlyansky, Yu.M. Zharinov BINP SB RAS, Novosibirsk, Russia F.A. Emanov, Yu. A. Rogovsky, A.I. Senchenko, A.A. Starostenko NSU, Novosibirsk, Russia
	The upgrade of VEPP-2000 e⁺e⁻ collider injection chain includes the connection to BINP Injection Complex (IC) via newly constructed transfer line K-500 as well as upgrade of the booster synchrotron BEP to the energy of 1 GeV. Modernization has started in the middle of 2013 and now the electron and positron beams with highly increased production rate together with top-up injection from BEP are ready to feed VEPP-2000 ring and provide design luminosity at the whole energy range limited only by beam-beam effects. The design and operation experience of IC damping ring, 250 m transfer channel and booster BEP dealing with 2.6 T magnets at top energy will be presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR018
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR028	Numerical Analysis of Stresses for the Target of the ILC 300 Hz Conventional Positron Source	target, simulation, linear-collider, collider	3838
	S. Jin, J. Gao IHEP, Beijing, People's Republic of China T. Omori KEK, Ibaraki, Japan P. Sievers CERN, Geneva, Switzerland
	A 300Hz conventional, e^- driven positron source for the ILC is proposed by an international team. In this paper, we focus on numerical analysis of dynamic stresses in the Tungsten target. These are driven by the pulsed e-beam, which causes rapid heating and subsequent, dynamic loads in the target which can lead to fracture and failure of it. A program of ANSYS workbench is used in the study. The dynamic stresses from both of extremely short (10 ns) and nominal (1μs) thermal pulses are systematically studied in various target related parts such as small spheres, cylinders. Particular attention has also been paid to the buckling of foils. (*) The first proposal was published in NIMA 672 (2012) 52-56 by T. Omori, et. al.. The authors come from seven institutes including KEK, Hiroshima U., DESY, ANL, IHEP, SOKENDAI, U. of Hamburg
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR028
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR036	Updates on the Sliding Contact Cooling ILC Positron Source Target Development	target, vacuum, undulator, radiation	3865
	W. Liu, D.S. Doran, R.A. Erck, G.R. Fenske, W. Gai, V.J. Guarino ANL, Argonne, Illinois, USA
	The R&D of the baseline positron source target for ILC is still ongoing after TDR due to the uncertainty of rotating vacuum seal and water cooling system of the fast spinning target wheel. Different institutes around the globe have proposed different approaches to tackle this issue. A spinning target wheel system with sliding contact cooling has been proposed by ANL. The proposed system eliminated the needs of rotating vacuum seal by using magnetic torque coupler to drive the solid spinning wheel target. The energy deposited from positron production process is taken away via cooling pads sliding against the spinning wheel. A full size test wheel has been built and some initial tests have been done with promising outcomes. Results of these tests are presented in this paper along with a plan for developing a prototype.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR036
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR037	TW-Structure Design and E-Field Study for CLIC Booster Linac	linac, booster, cavity, electron	3868
	E. Darvish Roknabadi IPM, Tehran, Iran S. Döbert CERN, Geneva, Switzerland
	Using the SUPERFISH code we present a design for a traveling wave (TW) structure of the Booster Linac for CLIC. The structure, consisting of thirty asymmetric cells attached to the beam pipes at two ends, works in 2Pi/3 operating mode at working frequency 2 GHz. The RF field transmitted through the designed cavity is prepared in an RF field data file to be used in the PARMELA code. We will then compare the resultant output PARMELA field with that of the ideal RF field which obtained from the usual method for a traveling wave structure. * Based on CLIC Note 1051, 2015
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR037
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPMB033

The Influence of Strip-line BPMs' Measuring Results Made by Edge of the Ultra-relativistic Electron Beam

simulation, electron, wakefield, linac

161

S.Z. Wang, N. Gan, X. Huang
IHEP, Beijing, People's Republic of China

This paper describes the impact on the measuring results of the stripline beam position monitor (BPM) produced by the edge of the ultra-relativistic electron beam when we take the transverse size of the beam into account. Simulations have been made by using the Wakefield Solver of CST Particle Studio. And the result of this influence at different ratio of beam horizontal width σ and the BPM inner diameter a has been obtained. This kind of influence has been observed in the stripline BPMs in the transfer line of Beijing Positron Electron Colliders upgraded version II (BEPCII). The research is useful when we design the inner diameter of the stripline BPMs for ultra-relativistic electron beam, meanwhile it provides reference to distinguish the invalid ones from the measuring results obtained by the stripline BPMs in the ultra-relativistic situation.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB033

Export •

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

MOPMB046

Design and Calculation Error Analysis of a High Order Mode Cavity Bunch Length Monitor

cavity, simulation, linac, electron

196

J.G. Guo, Q. Luo, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: National Science Foundation of China (11375178) and Fundamental Research Funds for the Central Universities (WK2310000046).
A two-cavity bunch length monitor for linac of positron source is designed. Fifth harmonic cavity resonates at 14.28 GHz (fifth harmonic of the linac fundamental frequency 2.856 GHz) with mode TM020, as this mode could provide larger cavity radius. Each cavity equipped with a filter to suppress unwanted signal. An improved bunch length calculation method was proposed. A simulation was conducted in CST Particle Studio for beam current from 100-300 mA, bunch length from 5-10 ps. Bunch length was calculated and compared by these two methods

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB046

Export •

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

MOPMR013

Development, Calibration and Application of New-generation Dissectors with Picosecond Temporal Resolution

electron, laser, radiation, operation

251

O.I. Meshkov, O. Anchugov, V.L. Dorohov, G.Y. Kurkin, A.V. Petrozhitskii, D.A. Shvedov, E.I. Zinin
BINP SB RAS, Novosibirsk, Russia
P.B. Gornostaev, M.Ya. Schelev, E.V. Shashkov, A. V. Smirnov, A.I. Zarovskii
GPI, Moscow, Russia

Funding: The presented experimental results were implemented due to financial support of the Russian Science Foundation (Projects N 14-29-00295)
A dissector is an electron-optical device designed for measurement of periodic light pulses of subnanosecond and picosecond duration. LI-602 dissector developed at BINP is widely used for routine measurements of a longitudinal profile of electron and positron beams at BINP electron-positron colliders and other similar installations]. This dissector is a part of many optical diagnostic systems and provides temporal resolution of about 20 ps. Recently* a new generation of picosecond dissectors were created on the basis of the PIF-01/S1 picosecond streak-image tube designed and manufactured at the General Physics Institute Photoelectronics Department (Moscow). The device has demonstrated a temporal resolution of 3-4 ps (FWHM). The procedure of temporal resolution calibration and results of application of the new-generation picosecond dissector are given in this work.
*E.I. Zinin, O.I. Meshkov. JINST, 2015 1748-0221 10 P10024 doi:10.1088/1748-0221/10/10/P10024

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR013

Export •

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

MOPMR052

Single-shot Bunch-by-Bunch Horizontal Beam Size Measurements using a Gated Camera at CesrTA

electron, ion, vacuum, synchrotron-radiation

364

S. Wang
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
R. Holtzapple
CalPoly, San Luis Obispo, California, USA

Funding: Work supported by NSF NSF PHY-1416318, PHYS-1068662, PHYS-1535696
A visible-light beam size monitor has been built and commissioned to measure transverse beam profiles at CESR-TA*. In order to eliminate beam jitter and to study bunch-by-bunch beam dynamics, a fast-gating camera has been utilized to measure single bunch transverse beam profiles. The minimum camera gate width is ~ 3ns which allows us to resolve single bunch beam dynamics along a CesrTA bunch train. Using single bunch interferometry at different bunch currents, we found that the horizontal beam sizes measured by gated camera are consistently less than those measured by a conventional CCD camera, demonstrating the elimination of turn-by-turn beam jitter with single shot capability. By stepping the camera trigger delay, we collected transverse beam profile images from each bunch in a 14ns-spacing 30-bunch train. The horizontal motion of each bunch as well as the horizontal beam size increases dramatically along an electron train but not along positron bunch trains under the same machine condition. The difference in single bunch horizontal dynamics may be a signature for the difference between electron cloud build-up for positron bunch trains versus ions present for electron bunch trains.
* S.T. Wang, D.L. Rubin, J. Conway, M. Palmer, D. Hartill, R. Campbell, R. Holtzapple, NIMA, 703 (2013) 80

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR052

Export •

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

TUOBB02

FACET-II Accelerator Research with Beams of Extreme Intensities

electron, linac, plasma, damping

1067

V. Yakimenko, Y. Cai, C.I. Clarke, S.Z. Green, C. Hast, M.J. Hogan, N. Lipkowitz, N. Phinney, G.R. White, G. Yocky
SLAC, Menlo Park, California, USA

In 2016, the second phase of SLAC's x-ray laser, the LCLS-II, will begin to use part of the tunnel occupied by FACET, and the world's only multi-GeV facility for advanced accelerator research will cease operation. FACET-II is a new test facility to provide DOE with the unique capability to develop advanced acceleration and coherent radiation techniques with high-energy electron and positron beams. FACET-II is an opportunity to build on the decades-long experience developed conducting advanced accelerator R&D at the FFTB and FACET and re-deploy HEP infrastructure in continued service of its mission. FACET-II provides a major upgrade over current FACET capabilities and the breadth of the potential research program makes it truly unique. It will synergistically pursue accelerator science that is vital to the future of both advanced acceleration techniques for High Energy Physics, ultra-high brightness beams for Basic Energy Science, and novel radiation sources for a wide variety of applications. The presentation will discuss FACET-II project status and plans for diverse experimental program.

Slides TUOBB02 [17.664 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOBB02

Export •

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

TUOCB01

First Commissioning of the SuperKEKB Vacuum System

vacuum, electron, photon, status

1086

Y. Suetsugu, H. Hisamatsu, T. Ishibashi, K. Kanazawa, K. Shibata, M. Shirai, S. Terui
KEK, Ibaraki, Japan

The SuperKEKB, an electron-positron collider with asymmetric energies in KEK, has started the first commissioning with beams this year. One of major tasks in the commissioning is the beam scrubbing of new beam pipes in order to increase the beam lifetime and to decrease the background noise of the particle detector in the coming physics run. The temperatures and the vacuum pressures of new vacuum components, such as the bellows chambers, gate valves and the beam collimators, should be checked in this run. The decrease rate in the vacuum pressure are measured to estimate the vacuum scrubbing effect. Reported here will be the results obtained during the first commissioning and the present status of the vacuum system.

Slides TUOCB01 [2.526 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUOCB01

Export •

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

TUPMB021

SLAC FACET-II Positron Damping Ring Magnet Design

lattice, damping, dipole, magnet-design

1154

M.A.G. Johansson
MAX IV Laboratory, Lund University, Lund, Sweden
Y. Cai, V. Yakimenko
SLAC, Menlo Park, California, USA

The FACET-II facility, currently being designed at SLAC, will contain a small ~20 m circumference, 335 MeV, positron damping ring. The ring has to fit in the existing linac tunnel, meaning that a compact lattice with short distances between magnets is required. The detailed magnet design is done in Opera-3d, with a finite element model of a full damping ring arc being simulated. This article presents this magnet design in a relatively early stage, with iteration between magnet and lattice design currently in progress.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMB021

Export •

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

TUPMY001

Very Low Emittance Muon Beam using Positron Beam on Target

target, emittance, collider, electron

1536

M. Antonelli, M.E. Biagini, M. Boscolo, A. Variola
INFN/LNF, Frascati (Roma), Italy
E. Bagli
INFN-Ferrara, Ferrara, Italy
G. Cavoto
INFN-Roma, Roma, Italy
P. Raimondi
ESRF, Grenoble, France

Muon beams are customarily obtained via K/π decays produced in proton interaction on target. In this paper we investigate the possibility to produce low emittance muon beams from electron-positron collisions at centre-of-mass energy just above the μ⁺{+}μ⁺{-} production threshold with maximal beam energy asymmetry, corresponding to a positron beam of about 45 GeV interacting on electrons on target. Performances on both amorphous and crystal target are presented, and the general scheme for the muon production will be given. We present the main features of this scheme with a first preliminary evaluation of the performances that could be achieved by a multi-TeV muon collider.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMY001

Export •

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

TUPOR021

Incoherent Vertical Emittance Growth from Electron Cloud at CesrTA

simulation, dipole, electron, emittance

1707

S. Poprocki, J.A. Crittenden, S.N. Hearth, J.D. Perrin, D. L. Rubin, S. Wang
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by the US National Science Foundation PHY-1416318, PHY-0734867, and PHY-1002467, and the U.S. Department of Energy DE-FC02-08ER41538
We report on measurements of electron cloud (EC) induced tune shifts and emittance growth at the Cornell Electron-Positron Storage Ring Test Accelerator (CesrTA) with comparison to tracking simulation predictions. The simulations are based on a weak-strong model of the interaction of the positron beam (weak) with the electron cloud (strong), using electric fields computed with established EC buildup simulation codes (ECLOUD). Experiments were performed with 2.1 GeV positrons in a 30 bunch train with 14 ns bunch spacing and 9 mm bunch length, plus a witness bunch at varying distance from the train to probe the cloud as it decays. Measurements of the horizontal and vertical coherent tune shifts and horizontal and vertical bunch size were obtained for a range of train and witness bunch currents, and compared to simulations.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR021

Export •

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

TUPOW019

Preliminary Concept of Fast Positron Source Based on Photo-injector

electron, target, simulation, linac

1785

Z. Chu, J.G. Guo, Q. Luo, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Supported by National Natural Science Foundation of China (11375178 and 11575181) and the Fundamental Research Funds for the Central Universities, Grant No WK2310000046
Based on the past experience in slow positron beam, researchers at NSRL/USTC proposed a fast positron source for detection of material deep tiny flaws. Different from conventional positron sources used in positron annihilation techniques, the planned positron source will be a positron production linac, similar to positron injectors used in colliders. To compress the positron pulse, the bombarding electron beam comes from a short bunch photo-injector. A computer simulation was performed using EGS4 and PARMELA code. The bombarding electron bunch is 300pC, with an energy of 30MeV. Simulations results showed that it is reasonable to expect a beam of more than 10⁵ positrons per pulse for future positron annihilation studies. Further work is to be done to achieve precise control of beam energy.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW019

Export •

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

WEPMW004

Progress in Detector Design and Installation for Measurements of Electron Cloud Trapping in Quadrupole Magnetic Fields at CesrTA

electron, quadrupole, detector, vacuum

2420

J.A. Crittenden, S. Barrett, M.G. Billing, K.A. Jones, Y. Li, T.I. O'Connell, K. Olear, S. Poprocki, D. L. Rubin, J.P. Sikora
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by the US National Science Foundation PHY-1416318, PHY-0734867, PHY-1002467, and the U.S. Department of Energy DE-FC02-08ER41538
Following up on our 2013 and 2014 measurements of electron cloud trapping in a quadrupole magnet with 7.4~T/m gradient in the 5.3~GeV positron storage ring at Cornell University, we have redesigned the shielded-stripline time-resolving electron detector and installed a wide-aperture quadrupole magnet at a location in the ring where its field can be compensated by a nearby quadrupole, thus allowing the first measurements of cloud trapping as a function of field gradient. The transverse acceptance of the electron detector has been tripled, allowing tests of model predictions indicating a dramatic cloud splitting effect which exhibits a threshold behavior as a function of bunch population. In addition, a vacuum chamber optimized for cloud buildup measurements using resonant microwave phenomena has been employed. We describe design considerations and modeling predictions for the upcoming 2016 data-taking run. This project is part of the CESR Test Accelerator program, which investigates performance limitations in low-emittance storage and damping rings.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW004

Export •

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

THPPA01

Demonstration of the Hollow Channel Plasma Wakefield Accelerator

plasma, laser, acceleration, wakefield

3202

S.J. Gessner, J.M. Allen, C.I. Clarke, J.-P. Delahaye, J.T. Frederico, S.Z. Green, C. Hast, M.J. Hogan, N. Lipkowitz, M.D. Litos, B.D. O'Shea, D.R. Walz, V. Yakimenko, G. Yocky
SLAC, Menlo Park, California, USA
E. Adli, C.A. Lindstrøm
University of Oslo, Oslo, Norway
W. An, C.E. Clayton, C. Joshi, K.A. Marsh, W.B. Mori, N. Vafaei-Najafabadi
UCLA, Los Angeles, California, USA
S. Corde, A. Doche
LOA, Palaiseau, France
W. Lu
TUB, Beijing, People's Republic of China

Funding: Work supported by DOE contract DE-AC02-76SF00515.
Over the past decade, there has been enormous progress in the field of beam and laser-driven plasma acceleration of electron beams. However, in order for plasma wakefield acceleration to be useful for a high-energy e⁺e^- collider, we need a technique for accelerating positrons in plasma as well. This is a unique challenge, because the plasma responds differently to electron and positron beams, with plasma electrons being pulled through the positron beam and creating a non-linear focusing force. Here, we demonstrate a technique called hollow channel acceleration that symmetrizes the wakefield response to beams of either charge. Using a transversely shaped laser pulse, we create an annular plasma with a fixed radius of 200 μm. We observe the acceleration of a positron bunch with energies up to 33.4 MeV in a 25 cm long channel, indicating an effective gradient greater than 100 MeV/m. This is the first demonstration of a technique that way be used for staged acceleration of positron beams in plasma.

Slides THPPA01 [5.647 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPPA01

Export •

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

THPMB013

Proposal of 6 GeV Energy Recovery Linac Hybrid Machine

electron, linac, cavity, undulator

3254

M. Shimada, K. Yokoya
KEK, Ibaraki, Japan
R. Hajima
JAEA, Ibaraki-ken, Japan
M. Tecimer
University of Hawaii at Manoa, Honolulu, USA

We proposed 6 GeV Energy Recovery Linac (ERL) as an intense gamma-ray source for the polarized positron source of International Linear Collider (ILC)*. In this scheme, Coherent Synchrotron Radiation from quasi-CW 6 GeV electron beam is stacked in optical cavity at middle infrared region, and it is used for inverse Compton scattering to generate 10 MeV polarized gamma-ray. The same 6 GeV superconducting linac accelerates both the electron and positron beams up to 5 GeV for injection to the dumping ring. Furthermore, it is available for X-ray light source by adding another recirculation loop. It can be expected as a diffraction limit light source at 10 keV, and the target of the brilliance is 10^22-23 ph/s/mm²/mrad²/b.w.0.1%.
* M. Shimada, Proceedings of IPAC'13

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB013

Export •

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

THPOR018

Comissioning of Upgraded VEPP-2000 Injection Chain

injection, electron, booster, linac

3811

D.E. Berkaev, A.V. Andrianov, K.V. Astrelina, V.V. Balakin, A.M. Barnyakov, O.V. Belikov, M.F. Blinov, D.V. Bochek, D. Bolkhovityanov, F.A. Emanov, A.R. Frolov, K. Gorchakov, Ye.A. Gusev, A.S. Kasaev, E. Kenzhbulatov, I. Koop, I.E. Korenev, G.Y. Kurkin, N.N. Lebedev, A.E. Levichev, P.V. Logatchov, A.P. Lysenko, D.A. Nikiforov, V.P. Prosvetov, Yu. A. Rogovsky, S.L. Samoylov, A.I. Senchenko, P.Yu. Shatunov, Y.M. Shatunov, D.B. Shwartz, A.A. Starostenko, I.M. Zemlyansky, Yu.M. Zharinov
BINP SB RAS, Novosibirsk, Russia
F.A. Emanov, Yu. A. Rogovsky, A.I. Senchenko, A.A. Starostenko
NSU, Novosibirsk, Russia

The upgrade of VEPP-2000 e⁺e⁻ collider injection chain includes the connection to BINP Injection Complex (IC) via newly constructed transfer line K-500 as well as upgrade of the booster synchrotron BEP to the energy of 1 GeV. Modernization has started in the middle of 2013 and now the electron and positron beams with highly increased production rate together with top-up injection from BEP are ready to feed VEPP-2000 ring and provide design luminosity at the whole energy range limited only by beam-beam effects. The design and operation experience of IC damping ring, 250 m transfer channel and booster BEP dealing with 2.6 T magnets at top energy will be presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR018

Export •

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

THPOR028

Numerical Analysis of Stresses for the Target of the ILC 300 Hz Conventional Positron Source

target, simulation, linear-collider, collider

3838

S. Jin, J. Gao
IHEP, Beijing, People's Republic of China
T. Omori
KEK, Ibaraki, Japan
P. Sievers
CERN, Geneva, Switzerland

A 300Hz conventional, e^- driven positron source for the ILC is proposed by an international team. In this paper, we focus on numerical analysis of dynamic stresses in the Tungsten target. These are driven by the pulsed e-beam, which causes rapid heating and subsequent, dynamic loads in the target which can lead to fracture and failure of it. A program of ANSYS workbench is used in the study. The dynamic stresses from both of extremely short (10 ns) and nominal (1μs) thermal pulses are systematically studied in various target related parts such as small spheres, cylinders. Particular attention has also been paid to the buckling of foils.
(*) The first proposal was published in NIMA 672 (2012) 52-56 by
T. Omori, et. al.. The authors come from seven institutes including KEK, Hiroshima U., DESY, ANL, IHEP, SOKENDAI, U. of Hamburg

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR028

Export •

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

THPOR036

Updates on the Sliding Contact Cooling ILC Positron Source Target Development

target, vacuum, undulator, radiation

3865

W. Liu, D.S. Doran, R.A. Erck, G.R. Fenske, W. Gai, V.J. Guarino
ANL, Argonne, Illinois, USA

The R&D of the baseline positron source target for ILC is still ongoing after TDR due to the uncertainty of rotating vacuum seal and water cooling system of the fast spinning target wheel. Different institutes around the globe have proposed different approaches to tackle this issue. A spinning target wheel system with sliding contact cooling has been proposed by ANL. The proposed system eliminated the needs of rotating vacuum seal by using magnetic torque coupler to drive the solid spinning wheel target. The energy deposited from positron production process is taken away via cooling pads sliding against the spinning wheel. A full size test wheel has been built and some initial tests have been done with promising outcomes. Results of these tests are presented in this paper along with a plan for developing a prototype.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR036

Export •

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

THPOR037

TW-Structure Design and E-Field Study for CLIC Booster Linac

linac, booster, cavity, electron

3868

E. Darvish Roknabadi
IPM, Tehran, Iran
S. Döbert
CERN, Geneva, Switzerland

Using the SUPERFISH code we present a design for a traveling wave (TW) structure of the Booster Linac for CLIC. The structure, consisting of thirty asymmetric cells attached to the beam pipes at two ends, works in 2Pi/3 operating mode at working frequency 2 GHz. The RF field transmitted through the designed cavity is prepared in an RF field data file to be used in the PARMELA code. We will then compare the resultant output PARMELA field with that of the ideal RF field which obtained from the usual method for a traveling wave structure.
* Based on CLIC Note 1051, 2015

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR037

Export •

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