eeFACT2018 - List of Keywords (lattice)

Paper	Title	Other Keywords	Page
TUOBB02	Off-momentum Optics at SuperKEKB	sextupole, coupling, optics, dynamic-aperture	71
	Y. Ohnishi, H. Koiso, A. Morita, K. Ohmi, H. Sugimoto KEK, Ibaraki, Japan K. Oide CERN, Meyrin, Switzerland
	The nano-beam scheme can squeeze the vertical beta function at the IP much smaller than the bunch length. It implies that the large chromaticity is generated in the vicinity of the final focus quadrupole magnets and the strong sextupoles are adopted to correct the chromaticity, for instance the local chromaticity corrections. While understanding of the off-momentum optics is important to optimize the dynamic aperture to make Touschek lifetime long and to reduce the luminosity degradation due to chromatic behaviors. In general, there is a discrepancy between measurements and those obtained from the optics model. The chromatic phase-advance is introduced to measure the off-momentum optics and correct by using sextupole magnets.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-TUOBB02
About •	paper received ※ 12 October 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOBB04	Different Optics within Large Energy Region at BEPCII	luminosity, emittance, operation, feedback	79
	C.H. Yu, Y. Bai, C.C. Du, Z. Duan, Y.Y. Guo, D. Ji, S.C. Jiang, Y. Jiao, Y.M. Peng, Q. Qin, Y.S. Sun, S.K. Tian, J.Q. Wang, N. Wang, X. Wang, Y. Wei, Wen. Wen, J. Wu, Xing. Xing, Xu. Xu, C. Zhang, Y. Zhang IHEP, Beijing, People’s Republic of China
	BEPCII is designed at the beam energy of 1.89 GeV. According to the requirements of high energy physics, BEPCII has been operated in the energy region from 1.0 GeV to 2.3 GeV since 2009. The energy region is quite large so that it is very important to select optics for the optimized luminosity. Different optics within different energy region at BEPCII will be introduced in detail in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-TUOBB04
About •	paper received ※ 23 September 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019
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TUYBA03	Beam-beam Blowup in the Presence of x-y Coupling Sources for FCC-ee	emittance, coupling, sextupole, simulation	112
	D. El Khechen, K. Oide, F. Zimmermann CERN, Geneva, Switzerland K. Oide KEK, Ibaraki, Japan
	FCC-ee, the lepton version of the Future Circular Collider (FCC), is a 100 Km future machine under study to be built at CERN. It acquires two experiments with a highest beam energy of 182.5 GeV. FCC-ee aims to operate at four different energies, with different luminosities to fulfill physics requirements. Beam-beam effects at such a high energy/luminosity machine are very challenging and require a deep understanding, especially in the presence of x-y coupling sources. Beam-beam effects include the beamstrahlung process, which limits the beam lifetime at high energies, as well as dynamic effects at the Interaction point (IP) which include changes in the beta functions and emittances. In this report, we will define the beam-beam effects and their behaviours in the FCC-ee highest energy lattice after introducing x-y coupling in the ring.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-TUYBA03
About •	paper received ※ 11 October 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEXBA03	Beam Blowup due to Lattice Coupling/Dispersion with/without Beam-beam	emittance, resonance, synchrotron, coupling	207
	K. Oide, D. El Khechen CERN, Meyrin, Switzerland
	Funding: Work supported by JSPS KAKENHI Grant Number 17K05475. Also supported by the European Commission under project EuCARD–2, grant agreement 312453, and under the Horizon 2020, grant agreement 654166. A significant blowup of the vertical emittance is observed in particle tracking in lattices with random skew quadrupoles, even without beam-beam effects with the FCC-ee lattice at ttbar. A Vlasov model well explains the blowup, and agrees with the tracking. This effect will set an additional limit on the goal of tuning of the vertical emittance of the lattice of colliders, well below the value at the collision.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-WEXBA03
About •	paper received ※ 25 September 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

TUOBB02

Off-momentum Optics at SuperKEKB

sextupole, coupling, optics, dynamic-aperture

71

Y. Ohnishi, H. Koiso, A. Morita, K. Ohmi, H. Sugimoto
KEK, Ibaraki, Japan
K. Oide
CERN, Meyrin, Switzerland

The nano-beam scheme can squeeze the vertical beta function at the IP much smaller than the bunch length. It implies that the large chromaticity is generated in the vicinity of the final focus quadrupole magnets and the strong sextupoles are adopted to correct the chromaticity, for instance the local chromaticity corrections. While understanding of the off-momentum optics is important to optimize the dynamic aperture to make Touschek lifetime long and to reduce the luminosity degradation due to chromatic behaviors. In general, there is a discrepancy between measurements and those obtained from the optics model. The chromatic phase-advance is introduced to measure the off-momentum optics and correct by using sextupole magnets.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-TUOBB02

About •

paper received ※ 12 October 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019

Export •

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

TUOBB04

Different Optics within Large Energy Region at BEPCII

luminosity, emittance, operation, feedback

79

C.H. Yu, Y. Bai, C.C. Du, Z. Duan, Y.Y. Guo, D. Ji, S.C. Jiang, Y. Jiao, Y.M. Peng, Q. Qin, Y.S. Sun, S.K. Tian, J.Q. Wang, N. Wang, X. Wang, Y. Wei, Wen. Wen, J. Wu, Xing. Xing, Xu. Xu, C. Zhang, Y. Zhang
IHEP, Beijing, People’s Republic of China

BEPCII is designed at the beam energy of 1.89 GeV. According to the requirements of high energy physics, BEPCII has been operated in the energy region from 1.0 GeV to 2.3 GeV since 2009. The energy region is quite large so that it is very important to select optics for the optimized luminosity. Different optics within different energy region at BEPCII will be introduced in detail in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-TUOBB04

About •

paper received ※ 23 September 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019

Export •

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

TUYBA03

Beam-beam Blowup in the Presence of x-y Coupling Sources for FCC-ee

emittance, coupling, sextupole, simulation

112

D. El Khechen, K. Oide, F. Zimmermann
CERN, Geneva, Switzerland
K. Oide
KEK, Ibaraki, Japan

FCC-ee, the lepton version of the Future Circular Collider (FCC), is a 100 Km future machine under study to be built at CERN. It acquires two experiments with a highest beam energy of 182.5 GeV. FCC-ee aims to operate at four different energies, with different luminosities to fulfill physics requirements. Beam-beam effects at such a high energy/luminosity machine are very challenging and require a deep understanding, especially in the presence of x-y coupling sources. Beam-beam effects include the beamstrahlung process, which limits the beam lifetime at high energies, as well as dynamic effects at the Interaction point (IP) which include changes in the beta functions and emittances. In this report, we will define the beam-beam effects and their behaviours in the FCC-ee highest energy lattice after introducing x-y coupling in the ring.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-TUYBA03

About •

paper received ※ 11 October 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019

Export •

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

WEXBA03

Beam Blowup due to Lattice Coupling/Dispersion with/without Beam-beam

emittance, resonance, synchrotron, coupling

207

K. Oide, D. El Khechen
CERN, Meyrin, Switzerland

Funding: Work supported by JSPS KAKENHI Grant Number 17K05475. Also supported by the European Commission under project EuCARD–2, grant agreement 312453, and under the Horizon 2020, grant agreement 654166.
A significant blowup of the vertical emittance is observed in particle tracking in lattices with random skew quadrupoles, even without beam-beam effects with the FCC-ee lattice at ttbar. A Vlasov model well explains the blowup, and agrees with the tracking. This effect will set an additional limit on the goal of tuning of the vertical emittance of the lattice of colliders, well below the value at the collision.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2018-WEXBA03

About •

paper received ※ 25 September 2018 paper accepted ※ 19 February 2019 issue date ※ 21 April 2019

Export •

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