IPAC2016 - Classification: 01 Circular and Linear Colliders / A24 Accelerators and Storage Rings, Other

Paper	Title	Page
THPOR015	CEPC Bunch Lengthening and Cavity HOM Analysis	3805
	H.J. Zheng, J. Gao, Y. Wang IHEP, Beijing, People's Republic of China
	In this paper we will show the higher order mode (HOM) analysis of the cavity for the Circular Electron-Positron Collider (CEPC) partial double ring (PDR) scheme. In order to study the single bunch longitudinal instability in CEPC, bunch lengthening and energy spread are estimated based on Gao's theory. Different models are used to study the bunch lengthening and energy spread of the ring.
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THPOR045	Analytical Estimation of ATF Beam Halo Distribution	3888
	D. Wang, J. Gao IHEP, Beijing, People's Republic of China P. Bambade LAL, Orsay, France T. Naito KEK, Ibaraki, Japan
	Funding: Work supported by the National Foundation of Natural Sciences (11505198 and 11575218) Halo distribution is a key topic for background study. This paper has developed an analytical method to give an estimation of ATF beam halo distribution. The equilibrium particle distribution of the beam tail in the ATF damping ring is calculated analytically with different emittance and different vacuum degree. The analytical results agree the measurements very well. This is a general method which can be applied to any electron rings.
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THPOR046	CEPC 650 MHz Klystron Development	3891
	Z.S. Zhou, D. Dong, S. Fukuda, Z.J. Lu, G. Pei, S.C. Wang, O. Xiao, .. Zaib-un-Nisa IHEP, Beijing, People's Republic of China S. Fukuda KEK, Ibaraki, Japan
	The CEPC collider beam power is about 100 MW, so the efficiency of amplifier is very important for cost of project implementation. The high power klystron is the more attractive because of its potential for higher eﬃciency than solid state amplifier. For CEPC klystron output power is not so high, the operation voltage can be a safe value. Advantage for single beam: reliable, low phase noise, some perspective technology can be used to improve efficiency. The accelerating frequency is 650 MHz, output power is a maximum power of 800kW, and efficiency is about 70%. In this paper, the specifications and developments of 650 MHz CW klystron, including the klystron gun prototype and future high efficiency consideration are summarized.
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THPOR047	Preliminary Concept and Key Technologies of HIEPA Accelerator	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.
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THPOR048	Beam Losses at CERNs PS and SPS Measured with Diamond Particle Detectors	3898
	F. Burkart, W. Bartmann, B. Dehning, E. Effinger, M.A. Fraser, B. Goddard, V. Kain, O. Stein CERN, Geneva, Switzerland E. Griesmayer CIVIDEC Instrumentation, Wien, Austria O. Stein University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
	Diamond particle detectors have been used in the LHC to measure fast particle losses with a nanosecond time resolution. In addition, these detectors were installed in the PS and the SPS. The detectors are mounted close to the extraction septum of the PS (transfer line to SPS) and the SPS (transfer lines TI2 and TI8 to LHC). Mainly, they monitor the losses occurring during the extraction process but the detectors are also able to measure turn-by-turn losses in the accelerators. In addition, detailed studies concerning losses due to ghost bunches were performed. This paper will describe the installed diamond detector setup, discuss the measurement results and possible loss mitigations.
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THPOR050	New Working Point for CERN Proton Synchrotron	3905
	F. Sperati, A. Beaumont, S.S. Gilardoni, D. Schoerling, M. Serluca, G. Sterbini CERN, Geneva, Switzerland
	The LHC High-luminosity project requests high brightness and intensity beams from the CERN Proton Synchrotron (PS). The generation of such beams is limited due to resonance effects at injection. The impact of resonances can be minimized by performing appropriate correction with dedicated magnets and by optimizing the tune working point. Currently the tune working point at injection is naturally set by the quadrupolar component generated by the one hundred combined function normal conducting magnets installed in the PS, and slightly corrected by low energy quadrupole magnets. In this paper, a study is presented exploiting the use of the available five auxiliary individually powered circuits to adjust the quadrupolar and higher-order multipole components for changing the tune integer at injection. Due to the non-linear contribution of each circuit to the magnetic field distribution a finite-element magnetic model was prepared to predict the required currents in the auxiliary coils. The magnetic model was benchmarked with magnetic measurements and then tested in the PS machine during dedicated machine development times.
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Paper

Title

Page

CEPC Bunch Lengthening and Cavity HOM Analysis

3805

H.J. Zheng, J. Gao, Y. Wang
IHEP, Beijing, People's Republic of China

In this paper we will show the higher order mode (HOM) analysis of the cavity for the Circular Electron-Positron Collider (CEPC) partial double ring (PDR) scheme. In order to study the single bunch longitudinal instability in CEPC, bunch lengthening and energy spread are estimated based on Gao's theory. Different models are used to study the bunch lengthening and energy spread of the ring.

Export •

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

THPOR045

Analytical Estimation of ATF Beam Halo Distribution

3888

D. Wang, J. Gao
IHEP, Beijing, People's Republic of China
P. Bambade
LAL, Orsay, France
T. Naito
KEK, Ibaraki, Japan

Funding: Work supported by the National Foundation of Natural Sciences (11505198 and 11575218)
Halo distribution is a key topic for background study. This paper has developed an analytical method to give an estimation of ATF beam halo distribution. The equilibrium particle distribution of the beam tail in the ATF damping ring is calculated analytically with different emittance and different vacuum degree. The analytical results agree the measurements very well. This is a general method which can be applied to any electron rings.

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

THPOR046

CEPC 650 MHz Klystron Development

3891

Z.S. Zhou, D. Dong, S. Fukuda, Z.J. Lu, G. Pei, S.C. Wang, O. Xiao, .. Zaib-un-Nisa
IHEP, Beijing, People's Republic of China
S. Fukuda
KEK, Ibaraki, Japan

The CEPC collider beam power is about 100 MW, so the efficiency of amplifier is very important for cost of project implementation. The high power klystron is the more attractive because of its potential for higher eﬃciency than solid state amplifier. For CEPC klystron output power is not so high, the operation voltage can be a safe value. Advantage for single beam: reliable, low phase noise, some perspective technology can be used to improve efficiency. The accelerating frequency is 650 MHz, output power is a maximum power of 800kW, and efficiency is about 70%. In this paper, the specifications and developments of 650 MHz CW klystron, including the klystron gun prototype and future high efficiency consideration are summarized.

Export •

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

THPOR047

Preliminary Concept and Key Technologies of HIEPA Accelerator

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.

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

THPOR048

Beam Losses at CERNs PS and SPS Measured with Diamond Particle Detectors

3898

F. Burkart, W. Bartmann, B. Dehning, E. Effinger, M.A. Fraser, B. Goddard, V. Kain, O. Stein
CERN, Geneva, Switzerland
E. Griesmayer
CIVIDEC Instrumentation, Wien, Austria
O. Stein
University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany

Diamond particle detectors have been used in the LHC to measure fast particle losses with a nanosecond time resolution. In addition, these detectors were installed in the PS and the SPS. The detectors are mounted close to the extraction septum of the PS (transfer line to SPS) and the SPS (transfer lines TI2 and TI8 to LHC). Mainly, they monitor the losses occurring during the extraction process but the detectors are also able to measure turn-by-turn losses in the accelerators. In addition, detailed studies concerning losses due to ghost bunches were performed. This paper will describe the installed diamond detector setup, discuss the measurement results and possible loss mitigations.

Export •

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

THPOR050

New Working Point for CERN Proton Synchrotron

3905

F. Sperati, A. Beaumont, S.S. Gilardoni, D. Schoerling, M. Serluca, G. Sterbini
CERN, Geneva, Switzerland

The LHC High-luminosity project requests high brightness and intensity beams from the CERN Proton Synchrotron (PS). The generation of such beams is limited due to resonance effects at injection. The impact of resonances can be minimized by performing appropriate correction with dedicated magnets and by optimizing the tune working point. Currently the tune working point at injection is naturally set by the quadrupolar component generated by the one hundred combined function normal conducting magnets installed in the PS, and slightly corrected by low energy quadrupole magnets. In this paper, a study is presented exploiting the use of the available five auxiliary individually powered circuits to adjust the quadrupolar and higher-order multipole components for changing the tune integer at injection. Due to the non-linear contribution of each circuit to the magnetic field distribution a finite-element magnetic model was prepared to predict the required currents in the auxiliary coils. The magnetic model was benchmarked with magnetic measurements and then tested in the PS machine during dedicated machine development times.

Export •

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