IPAC2016 - List of Keywords (brightness)

Paper	Title	Other Keywords	Page
MOPMB018	Metrological Characterization of the Bunch Length Measurement by Means of a RF Deflector at the ELI-NP Compton Gamma source	linac, electron, simulation, laser	122
	L. Sabato U. Sannio, Benevento, Italy D. Alesini, C. Vaccarezza, A. Variola INFN/LNF, Frascati (Roma), Italy P. Arpaia CERN, Geneva, Switzerland P. Arpaia, A. Liccardo Naples University Federico II, Science and Technology Pole, Napoli, Italy A. Giribono University of Rome La Sapienza, Rome, Italy A. Mostacci, L. Palumbo Rome University La Sapienza, Roma, Italy L. Sabato INFN-Napoli, Napoli, Italy
	Bunch length measurement in linac can be carried out using a RF deflector, which provides a transverse kick to the beam. The transverse beam size on a screen, placed after the RF deflector, represents the bunch length. In this paper, the metrological characterization of the bunch length measurement technique is proposed. The uncertainty and the systematic errors are estimated by means of a sensitivity analysis to the measurement parameters. The proposed approach has been validated through simulation by means of ELEGANT code on the parameters interesting for the electron linac of the Compton source at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP).
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB018
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB022	Conceptual Design for SR Monitor in the FCC Beam Emittance (Size) Diagnostic	extraction, diagnostics, emittance, vacuum	133
	T.M. Mitsuhashi, K. Oide KEK, Ibaraki, Japan F. Zimmermann CERN, Geneva, Switzerland
	A conceptual design for emittance diagnostics through a beam size measurement using the synchrotron radiation (SR) is studied for the FCC. For the FCC-ee, a X-ray interferometer is propose to measure a nano-radian order vertical beam size. Also conceptual design of SR monitor is studied for FCC-hh. In the FCC-hh, visible SR will emitted from bending magnet in the energy range from the injection (3TeV) to top energy (50TeV). Hard X-ray SR will only available in the energy upper than 30TeV. The various instrumentations using the visible SR is usable for all energy range. Around the top energy, the X-ray pinhole camera will convenient for beam diagnostics of emittance through the beam size measurement.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB022
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB041	Modified Trigger Mode of Streak Camera to Measure Bunch Longitudinal Distribution in HLS II	electron, optics, controls, hardware	184
	H. Li, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, F.F. Wu, Y.L. Yang, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Supported by the National Science Foundation of China (11575181, 11175173) In Hefei Light Source, the streak camera was used to measure the bunch length and longitudinal distribution using synchronous light. As the RF frequency of HLS II was 204MHz, the streak camera worked at the frequency of 102MHz (half of 204MHz). Because of the bunch lengthening, the streak camera faced the problem, the streak image on the phosphor screen will overlap when the bunch length was above 200.5ps@5% linear error and 10% overlap. In order to solve this problem, an effective solution was to change the working frequency of the streak camera to 136MHz (two thirds of 204MHz), and then the streak image on the phosphor screen will overlap when the bunch length was above 285.6ps@5% linear error and 10% overlap. So a front-end electronic was needed before the synchronizing signals feed into the streak camera. The front-end electronic was designed to convert the 204MHz synchronizing signal to 136MHz.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB041
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMR028	Emittance Characterisation of High Brightness Beams in the CERN PS	emittance, proton, synchrotron, extraction	299
	G. Sterbini, J.F. Comblin, V. Forte, A. Guerrero, E. Piselli CERN, Geneva, Switzerland V. Forte Université Blaise Pascal, Clermont-Ferrand, France
	Measurements in the CERN Proton Synchrotron showed that achieving the required accuracy for the emittance characterisation of high brightness beams is challenging. Some of the present limits can be related to systematic errors in the wire scanner calibration or, for the horizontal emittance determination, in the assumptions adopted while deconvoluting the contribution of the longitudinal plane from the measured transverse profile. We present in this paper the results of a beam-based test of the wire scanner calibration and of a general numerical deconvolution algorithm to compute the betatronic profile starting from the measured ones. In addition to the bunch train average emittance, a bunch-by-bunch transverse emittance measurement would increase the potential to understand, optimise and monitor the beam performance. In 2015 the first PS bunch-by-bunch measurement chain was setup. The results are reported and discussed.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR028
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOR021	Space Charge Studies with High Intensity Single Bunch Beams in the CERN SPS	emittance, injection, resonance, space-charge	644
	H. Bartosik, F. Schmidt CERN, Geneva, Switzerland A. Oeftiger EPFL, Lausanne, Switzerland M. Titze HZB, Berlin, Germany
	In order to reach the target beam parameters of the LHC injectors upgrade (LIU) project the beam degradation due to losses and emittance growth on the long injection plateau of the SPS needs to be minimized. A detailed study of the dependence of losses, transverse emittance blow-up and transverse beam tail creation as function of the working point is presented here for a high brightness single bunch beam with a vertical space charge tune spread of about 0.2 on the 26 GeV injection plateau. The beam behaviour close to important betatron resonances is characterised and a region in the tune diagram with minimal beam degradation is identified. Implications about the performance for LIU beams are discussed.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOY059	LHC Injectors Upgrade (LIU) Project at CERN	ion, injection, proton, linac	992
	E.N. Shaposhnikova, J. Coupard, H. Damerau, A. Funken, S.S. Gilardoni, B. Goddard, K. Hanke, L. Kobzeva, A.M. Lombardi, D. Manglunki, S. Mataguez, M. Meddahi, B. Mikulec, G. Rumolo, R. Scrivens, M. Vretenar CERN, Geneva, Switzerland
	A massive improvement program of the LHC injector chain is presently being conducted under the LIU project. For the proton chain, this includes the replacement of Linac2 with Linac4 as well as all necessary upgrades to the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS) and Super Proton Synchrotron (SPS), aimed at producing beams with the challenging High Luminosity LHC (HL-LHC) parameters. Regarding the heavy ions, plans to improve the performance of Linac3 and the Low Energy Ion Ring (LEIR) are also pursued under the general LIU program. The full LHC injection chain returned to operation after Long Shutdown 1, with extended beam studies taking place in Run 2. A general project Cost and Schedule Review also took place in March 2015, and several dedicated LIU project reviews were held to address issues awaiting pending decisions. In view of these developments, 2014 and 2015 have been key years to define a number of important aspects of the final LIU path. This paper will describe the reviewed LIU roadmap and revised performance objectives of the main upgrades, including the work status and outlook in terms of the required installation and commissioning stages.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY059
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMR050	Upgrades to the SPS-to-LHC Transfer Line Beam Stoppers for the LHC High-Luminosity Era	extraction, proton, simulation, kicker	1367
	V. Kain, R. Esposito, M.A. Fraser, B. Goddard, M. Meddahi, A. Perillo Marcone, G.E. Steele, F.M. Velotti CERN, Geneva, Switzerland
	Each of the 3 km long transfer lines between the SPS and the LHC is equipped with two beam stoppers (TEDs), one at the beginning of the line and one close to the LHC injection point, which need to absorb the full transferred beam. The beam stoppers are used for setting up the SPS extractions and transfer lines with beam without having to inject into the LHC. Energy deposition and thermo-mechanical simulations have, however, shown that the TEDs will not be robust enough to safely absorb the high intensity beams foreseen for the high-luminosity LHC era. This paper will summarize the simulation results and limitations for upgrading the beam stoppers. An outline of the hardware upgrade strategy for the TEDs together with modifications to the SPS extraction interlock system to enforce intensity limitations for beam on the beam stoppers will be given.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR050
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMY013	A Spatially Separated Two Frequency RF Gun Design for Beam Brightness Improvement	gun, emittance, laser, cavity	2572
	Z. Zhang, C.-X. Tang, Z. Zhang TUB, Beijing, People's Republic of China H.J. Qian LBNL, Berkeley, California, USA
	Recent theoretical and experimental studies shows that transverse beam brightness of photoinjector can be improved by cigar beam photoemission, and beam peak current are then increased with a RF buncher following the gun. We apply this concept to a S-band photoinjector by adding a harmonic RF buncher closely to a S-band RF gun, forming a compact spatially separated two frequency RF gun, targeting a 200 pC beam with emittance < 0.2 mm·mrad and 30 A peak current. Both S/X-band and S/C-band combinations are considered, and an optimized solution with 30 A peak current and 0.1 mm·mrad slice emittance are presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY013
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMY039	Time Response Measurements for Transmission-Type GaAs/GaAsP Superlattice Photocathodes	electron, laser, cavity, gun	2641
	N. Yamamoto, X.J. Jin KEK, Ibaraki, Japan M. Hosaka, Y. Takashima, K. Yamaguchi Nagoya University, Nagoya, Japan M. Katoh UVSOR, Okazaki, Japan
	Polarized electron beam is essential for future electron-positron colliders and electron-ion colliders. Recently we have developed the strain compensated superlattice (SL) photocathode. In the strain compensated SLs, the equivalent compressive and tensile strains introduced in the well and barrier SL layers so that strain relaxation is effectively suppressed with increasing the SL layer thickness and high crystal quality can be expected. In this study, we fabricated the GaAs/GaAsP strain compensated SLs with the thickness up to 90-pair SL layers. Up to now, the electron spin polarization of 92 % and the quantum efficiency of 1.6 % were simultaneously achieved from 24-pair sample. In this study, to compare the time response performances with the SL thicknesses, the measurements were carried out for conventional and strain compensated SL PCs. We show the measurement results and discuss the physics.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY039
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW049	Physics Design Progress towards a Diffraction Limited Upgrade of the ALS	emittance, lattice, injection, dynamic-aperture	2956
	C. Steier, J.M. Byrd, S. De Santis, H. Nishimura, D. Robin, F. Sannibale, C. Sun, M. Venturini, W. Wan LBNL, Berkeley, California, USA
	Funding: This work was supported by the Laboratory Directed Research and Development Program of Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE-AC02-05CH11231. Improvements in brightness and coherent flux of more than two orders of magnitude are possible using multi bend achromat lattice designs. These improvements can be implemented as upgrades of existing facilities, like the proposed upgrade of the Advanced Light Source. We will describe the progress in the physics design of this upgrade, including lattice evolution, error tolerance studies, simulations of collective effects, and intra beam scattering.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW049
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOY015	Longitudinal Bram Dynamics at Rf-Compressor	gun, space-charge, simulation, electron	3011
	A.V. Andrianov BINP SB RAS, Novosibirsk, Russia
	Nowadays the usage of charged particle beams for study of nature became widespread. Modern experiments are require particle beams with duration around hundreds femtosecond. Relatively simple and cheap method of production such pulses is using RF-gun with photocathode and then the special insertion device which compress the beam. The paper described the RF-compressor for the electron beam. In result of work was obtained a device configuration. Electromagnetic field configuration and distribution were simulated for the configuration. Beam dynamics was computed in this field distribution. Incoming beam parameters are following: beam length is 1-5ps, beam charge is 0.1-2pC and energy is 3MeV. Output beam duration was compressed to less than 150fs. Influence of RF-compressor at beam parameters was estimated.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOY015
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THOAB03	Ultrafast Electron Microscopy using 100 Femtosecond Relativistic-Energy Electron Beam	electron, emittance, gun, laser	3183
	J. Yang, K. Kan, K. Tanimura, Y. Yoshida ISIR, Osaka, Japan J. Urakawa KEK, Ibaraki, Japan
	An ultrafast detection technique on 100 fs time scales over sub-nanometer (even atomic) spatial dimensions has long been a goal for the scientists to reveal and understand the ultrafast structural-change induced dynamics in materials. In this paper, the generation of femtosecond electron pulses using the RF gun and the first prototype of femtosecond time-resolved relativistic-energy ultrafast electron microscopy (UEM) are reported. Finally, both relativistic-energy electron diffraction and image measurements in the UEM prototype are presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THOAB03
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMB012	The HMBA Lattice Optimization for the New 3 GeV Light Source	lattice, emittance, storage-ring, injection	3251
	K. Harada, M. Adachi, N. Funamori, T. Honda, Y. Kobayashi, N. Nakamura, K. Oide, H. Sakai, S. Sakanaka, K. Tsuchiya KEK, Ibaraki, Japan
	For the design study of the HMBA (hybrid multi bend achromat) type most advanced light source, the new storage ring was designed from the lattice of the phase II upgrade project of the ESRF (ESRF II). Although the original 3 GeV test lattice from Dr. Pantaleo Raimondi of ESRF has no problem about the optical and magnetic parameters including the dynamic aperture, we reduce the cell numbers and inserted the short straight sections for the in-vacuum short-gap undulators. After the optimization of the linear and non-linear optics as the original design principle of ESRF II, the altered lattice has the circumference of about 440 m with 16 HMBA cells, the emittance about 440 pm rad with the intra-beam scattering effect at the beam current of 500 mA, and the large dynamic aperture of about 2 cm at the injection point even with the usual magnetic errors.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB012
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOR047	Preliminary Concept and Key Technologies of HIEPA Accelerator	collider, synchrotron, luminosity, emittance	3895
	Z.R. Zhou, Q. Luo, L. Wang, W. Xu, B. Zhang 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 High energy physicists proposed a new collider: super tau-charm factory. The name of the project is high intensity electron positron accelerator facility. As high intensity electron positron collider, it runs in an energy range of 2-7 GeV. As an advanced light source, it can also provide high quality synchrotron radiation from VUV to soft X-ray. The facility will be a symmetrical two-ring collider located at Hefei. This paper shows preliminary conception of the storage rings.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR047
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOW020	S-Band Photoinjector Investigations by Multiobjective Genetic Optimizer	emittance, laser, gun, cathode	3979
	H.J. Qian, D. Filippetto, F. Sannibale LBNL, Berkeley, California, USA
	Photoinjectors has witnessed great progress in the past few decades, with low duty cycle high gradient guns, such as normal conducting S/L band gun, pushing the peak beam brightness frontier, and CW guns, such as DC gun, SRF gun and VHF gun, pushing the average beam brightness frontier. Due to different degrees of complexity, pulsed high gradient photoinjectors are usually optimized by manual scans, while CW photoinjectors are optimized by multi-objective genetic optimizers. In this paper, a multi-objective genetic optimizer is used to revisit S-band photoinjector beam brightness optimizations, showing a trade-off between peak current and transverse emittance, with the optimized injector layout depending on bunch charge and peak current. For 200 pC case, the final beam core brightness at injector exit is close to cathode maximum brightness in the 'cigar beam' regime. Assuming a thermal emittance of 0.5 μm/mm and a beam charge of 200 pC, about 90 nm slice emittance at 20 A peak current is achieved.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

Metrological Characterization of the Bunch Length Measurement by Means of a RF Deflector at the ELI-NP Compton Gamma source

linac, electron, simulation, laser

122

L. Sabato
U. Sannio, Benevento, Italy
D. Alesini, C. Vaccarezza, A. Variola
INFN/LNF, Frascati (Roma), Italy
P. Arpaia
CERN, Geneva, Switzerland
P. Arpaia, A. Liccardo
Naples University Federico II, Science and Technology Pole, Napoli, Italy
A. Giribono
University of Rome La Sapienza, Rome, Italy
A. Mostacci, L. Palumbo
Rome University La Sapienza, Roma, Italy
L. Sabato
INFN-Napoli, Napoli, Italy

Bunch length measurement in linac can be carried out using a RF deflector, which provides a transverse kick to the beam. The transverse beam size on a screen, placed after the RF deflector, represents the bunch length. In this paper, the metrological characterization of the bunch length measurement technique is proposed. The uncertainty and the systematic errors are estimated by means of a sensitivity analysis to the measurement parameters. The proposed approach has been validated through simulation by means of ELEGANT code on the parameters interesting for the electron linac of the Compton source at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP).

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB018

Export •

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

MOPMB022

Conceptual Design for SR Monitor in the FCC Beam Emittance (Size) Diagnostic

extraction, diagnostics, emittance, vacuum

133

T.M. Mitsuhashi, K. Oide
KEK, Ibaraki, Japan
F. Zimmermann
CERN, Geneva, Switzerland

A conceptual design for emittance diagnostics through a beam size measurement using the synchrotron radiation (SR) is studied for the FCC. For the FCC-ee, a X-ray interferometer is propose to measure a nano-radian order vertical beam size. Also conceptual design of SR monitor is studied for FCC-hh. In the FCC-hh, visible SR will emitted from bending magnet in the energy range from the injection (3TeV) to top energy (50TeV). Hard X-ray SR will only available in the energy upper than 30TeV. The various instrumentations using the visible SR is usable for all energy range. Around the top energy, the X-ray pinhole camera will convenient for beam diagnostics of emittance through the beam size measurement.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB022

Export •

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

MOPMB041

Modified Trigger Mode of Streak Camera to Measure Bunch Longitudinal Distribution in HLS II

electron, optics, controls, hardware

184

H. Li, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, F.F. Wu, Y.L. Yang, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Supported by the National Science Foundation of China (11575181, 11175173)
In Hefei Light Source, the streak camera was used to measure the bunch length and longitudinal distribution using synchronous light. As the RF frequency of HLS II was 204MHz, the streak camera worked at the frequency of 102MHz (half of 204MHz). Because of the bunch lengthening, the streak camera faced the problem, the streak image on the phosphor screen will overlap when the bunch length was above 200.5ps@5% linear error and 10% overlap. In order to solve this problem, an effective solution was to change the working frequency of the streak camera to 136MHz (two thirds of 204MHz), and then the streak image on the phosphor screen will overlap when the bunch length was above 285.6ps@5% linear error and 10% overlap. So a front-end electronic was needed before the synchronizing signals feed into the streak camera. The front-end electronic was designed to convert the 204MHz synchronizing signal to 136MHz.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMB041

Export •

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

MOPMR028

Emittance Characterisation of High Brightness Beams in the CERN PS

emittance, proton, synchrotron, extraction

299

G. Sterbini, J.F. Comblin, V. Forte, A. Guerrero, E. Piselli
CERN, Geneva, Switzerland
V. Forte
Université Blaise Pascal, Clermont-Ferrand, France

Measurements in the CERN Proton Synchrotron showed that achieving the required accuracy for the emittance characterisation of high brightness beams is challenging. Some of the present limits can be related to systematic errors in the wire scanner calibration or, for the horizontal emittance determination, in the assumptions adopted while deconvoluting the contribution of the longitudinal plane from the measured transverse profile. We present in this paper the results of a beam-based test of the wire scanner calibration and of a general numerical deconvolution algorithm to compute the betatronic profile starting from the measured ones. In addition to the bunch train average emittance, a bunch-by-bunch transverse emittance measurement would increase the potential to understand, optimise and monitor the beam performance. In 2015 the first PS bunch-by-bunch measurement chain was setup. The results are reported and discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR028

Export •

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

MOPOR021

Space Charge Studies with High Intensity Single Bunch Beams in the CERN SPS

emittance, injection, resonance, space-charge

644

H. Bartosik, F. Schmidt
CERN, Geneva, Switzerland
A. Oeftiger
EPFL, Lausanne, Switzerland
M. Titze
HZB, Berlin, Germany

In order to reach the target beam parameters of the LHC injectors upgrade (LIU) project the beam degradation due to losses and emittance growth on the long injection plateau of the SPS needs to be minimized. A detailed study of the dependence of losses, transverse emittance blow-up and transverse beam tail creation as function of the working point is presented here for a high brightness single bunch beam with a vertical space charge tune spread of about 0.2 on the 26 GeV injection plateau. The beam behaviour close to important betatron resonances is characterised and a region in the tune diagram with minimal beam degradation is identified. Implications about the performance for LIU beams are discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOR021

Export •

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

MOPOY059

LHC Injectors Upgrade (LIU) Project at CERN

ion, injection, proton, linac

992

E.N. Shaposhnikova, J. Coupard, H. Damerau, A. Funken, S.S. Gilardoni, B. Goddard, K. Hanke, L. Kobzeva, A.M. Lombardi, D. Manglunki, S. Mataguez, M. Meddahi, B. Mikulec, G. Rumolo, R. Scrivens, M. Vretenar
CERN, Geneva, Switzerland

A massive improvement program of the LHC injector chain is presently being conducted under the LIU project. For the proton chain, this includes the replacement of Linac2 with Linac4 as well as all necessary upgrades to the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS) and Super Proton Synchrotron (SPS), aimed at producing beams with the challenging High Luminosity LHC (HL-LHC) parameters. Regarding the heavy ions, plans to improve the performance of Linac3 and the Low Energy Ion Ring (LEIR) are also pursued under the general LIU program. The full LHC injection chain returned to operation after Long Shutdown 1, with extended beam studies taking place in Run 2. A general project Cost and Schedule Review also took place in March 2015, and several dedicated LIU project reviews were held to address issues awaiting pending decisions. In view of these developments, 2014 and 2015 have been key years to define a number of important aspects of the final LIU path. This paper will describe the reviewed LIU roadmap and revised performance objectives of the main upgrades, including the work status and outlook in terms of the required installation and commissioning stages.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY059

Export •

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

TUPMR050

Upgrades to the SPS-to-LHC Transfer Line Beam Stoppers for the LHC High-Luminosity Era

extraction, proton, simulation, kicker

1367

V. Kain, R. Esposito, M.A. Fraser, B. Goddard, M. Meddahi, A. Perillo Marcone, G.E. Steele, F.M. Velotti
CERN, Geneva, Switzerland

Each of the 3 km long transfer lines between the SPS and the LHC is equipped with two beam stoppers (TEDs), one at the beginning of the line and one close to the LHC injection point, which need to absorb the full transferred beam. The beam stoppers are used for setting up the SPS extractions and transfer lines with beam without having to inject into the LHC. Energy deposition and thermo-mechanical simulations have, however, shown that the TEDs will not be robust enough to safely absorb the high intensity beams foreseen for the high-luminosity LHC era. This paper will summarize the simulation results and limitations for upgrading the beam stoppers. An outline of the hardware upgrade strategy for the TEDs together with modifications to the SPS extraction interlock system to enforce intensity limitations for beam on the beam stoppers will be given.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR050

Export •

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

WEPMY013

A Spatially Separated Two Frequency RF Gun Design for Beam Brightness Improvement

gun, emittance, laser, cavity

2572

Z. Zhang, C.-X. Tang, Z. Zhang
TUB, Beijing, People's Republic of China
H.J. Qian
LBNL, Berkeley, California, USA

Recent theoretical and experimental studies shows that transverse beam brightness of photoinjector can be improved by cigar beam photoemission, and beam peak current are then increased with a RF buncher following the gun. We apply this concept to a S-band photoinjector by adding a harmonic RF buncher closely to a S-band RF gun, forming a compact spatially separated two frequency RF gun, targeting a 200 pC beam with emittance < 0.2 mm·mrad and 30 A peak current. Both S/X-band and S/C-band combinations are considered, and an optimized solution with 30 A peak current and 0.1 mm·mrad slice emittance are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY013

Export •

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

WEPMY039

Time Response Measurements for Transmission-Type GaAs/GaAsP Superlattice Photocathodes

electron, laser, cavity, gun

2641

N. Yamamoto, X.J. Jin
KEK, Ibaraki, Japan
M. Hosaka, Y. Takashima, K. Yamaguchi
Nagoya University, Nagoya, Japan
M. Katoh
UVSOR, Okazaki, Japan

Polarized electron beam is essential for future electron-positron colliders and electron-ion colliders. Recently we have developed the strain compensated superlattice (SL) photocathode. In the strain compensated SLs, the equivalent compressive and tensile strains introduced in the well and barrier SL layers so that strain relaxation is effectively suppressed with increasing the SL layer thickness and high crystal quality can be expected. In this study, we fabricated the GaAs/GaAsP strain compensated SLs with the thickness up to 90-pair SL layers. Up to now, the electron spin polarization of 92 % and the quantum efficiency of 1.6 % were simultaneously achieved from 24-pair sample. In this study, to compare the time response performances with the SL thicknesses, the measurements were carried out for conventional and strain compensated SL PCs. We show the measurement results and discuss the physics.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMY039

Export •

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

WEPOW049

Physics Design Progress towards a Diffraction Limited Upgrade of the ALS

emittance, lattice, injection, dynamic-aperture

2956

C. Steier, J.M. Byrd, S. De Santis, H. Nishimura, D. Robin, F. Sannibale, C. Sun, M. Venturini, W. Wan
LBNL, Berkeley, California, USA

Funding: This work was supported by the Laboratory Directed Research and Development Program of Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE-AC02-05CH11231.
Improvements in brightness and coherent flux of more than two orders of magnitude are possible using multi bend achromat lattice designs. These improvements can be implemented as upgrades of existing facilities, like the proposed upgrade of the Advanced Light Source. We will describe the progress in the physics design of this upgrade, including lattice evolution, error tolerance studies, simulations of collective effects, and intra beam scattering.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOW049

Export •

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

WEPOY015

Longitudinal Bram Dynamics at Rf-Compressor

gun, space-charge, simulation, electron

3011

A.V. Andrianov
BINP SB RAS, Novosibirsk, Russia

Nowadays the usage of charged particle beams for study of nature became widespread. Modern experiments are require particle beams with duration around hundreds femtosecond. Relatively simple and cheap method of production such pulses is using RF-gun with photocathode and then the special insertion device which compress the beam. The paper described the RF-compressor for the electron beam. In result of work was obtained a device configuration. Electromagnetic field configuration and distribution were simulated for the configuration. Beam dynamics was computed in this field distribution. Incoming beam parameters are following: beam length is 1-5ps, beam charge is 0.1-2pC and energy is 3MeV. Output beam duration was compressed to less than 150fs. Influence of RF-compressor at beam parameters was estimated.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOY015

Export •

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

THOAB03

Ultrafast Electron Microscopy using 100 Femtosecond Relativistic-Energy Electron Beam

electron, emittance, gun, laser

3183

J. Yang, K. Kan, K. Tanimura, Y. Yoshida
ISIR, Osaka, Japan
J. Urakawa
KEK, Ibaraki, Japan

An ultrafast detection technique on 100 fs time scales over sub-nanometer (even atomic) spatial dimensions has long been a goal for the scientists to reveal and understand the ultrafast structural-change induced dynamics in materials. In this paper, the generation of femtosecond electron pulses using the RF gun and the first prototype of femtosecond time-resolved relativistic-energy ultrafast electron microscopy (UEM) are reported. Finally, both relativistic-energy electron diffraction and image measurements in the UEM prototype are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THOAB03

Export •

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

THPMB012

The HMBA Lattice Optimization for the New 3 GeV Light Source

lattice, emittance, storage-ring, injection

3251

K. Harada, M. Adachi, N. Funamori, T. Honda, Y. Kobayashi, N. Nakamura, K. Oide, H. Sakai, S. Sakanaka, K. Tsuchiya
KEK, Ibaraki, Japan

For the design study of the HMBA (hybrid multi bend achromat) type most advanced light source, the new storage ring was designed from the lattice of the phase II upgrade project of the ESRF (ESRF II). Although the original 3 GeV test lattice from Dr. Pantaleo Raimondi of ESRF has no problem about the optical and magnetic parameters including the dynamic aperture, we reduce the cell numbers and inserted the short straight sections for the in-vacuum short-gap undulators. After the optimization of the linear and non-linear optics as the original design principle of ESRF II, the altered lattice has the circumference of about 440 m with 16 HMBA cells, the emittance about 440 pm rad with the intra-beam scattering effect at the beam current of 500 mA, and the large dynamic aperture of about 2 cm at the injection point even with the usual magnetic errors.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB012

Export •

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

THPOR047

Preliminary Concept and Key Technologies of HIEPA Accelerator

collider, synchrotron, luminosity, emittance

3895

Z.R. Zhou, Q. Luo, L. Wang, W. Xu, B. Zhang
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
High energy physicists proposed a new collider: super tau-charm factory. The name of the project is high intensity electron positron accelerator facility. As high intensity electron positron collider, it runs in an energy range of 2-7 GeV. As an advanced light source, it can also provide high quality synchrotron radiation from VUV to soft X-ray. The facility will be a symmetrical two-ring collider located at Hefei. This paper shows preliminary conception of the storage rings.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOR047

Export •

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

THPOW020

S-Band Photoinjector Investigations by Multiobjective Genetic Optimizer

emittance, laser, gun, cathode

3979

H.J. Qian, D. Filippetto, F. Sannibale
LBNL, Berkeley, California, USA

Photoinjectors has witnessed great progress in the past few decades, with low duty cycle high gradient guns, such as normal conducting S/L band gun, pushing the peak beam brightness frontier, and CW guns, such as DC gun, SRF gun and VHF gun, pushing the average beam brightness frontier. Due to different degrees of complexity, pulsed high gradient photoinjectors are usually optimized by manual scans, while CW photoinjectors are optimized by multi-objective genetic optimizers. In this paper, a multi-objective genetic optimizer is used to revisit S-band photoinjector beam brightness optimizations, showing a trade-off between peak current and transverse emittance, with the optimized injector layout depending on bunch charge and peak current. For 200 pC case, the final beam core brightness at injector exit is close to cathode maximum brightness in the 'cigar beam' regime. Assuming a thermal emittance of 0.5 μm/mm and a beam charge of 200 pC, about 90 nm slice emittance at 20 A peak current is achieved.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW020

Export •

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