eeFACT2016 - List of Authors (Oide, K.)

Paper	Title	Page
MOOTH1	Overview of High Energy e⁺e⁻ Factories	1
	K. Oide KEK, Ibaraki, Japan
	Designs of e⁺e⁻ colliders from the Z-pole and above are introduced. Two projects, CEPC and FCC-ee, are discussed. If we compare their schemes, a partial double ring (CEPC) and a full double ring (FCC-ee), find several important differences that affect the performance. On the other hand, there are a number of similarities in both designs, such as the crab-waist scheme, crossing angle, optimization of the dynamic aperture, etc.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-MOOTH1
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TUT2H5	Towards a Preliminary FCC-ee Injector Design	90
	S. Ogur, Y. Papaphilippou, F. Zimmermann CERN, Geneva, Switzerland A.M. Barnyakov, A.E. Levichev, D.A. Nikiforov BINP SB RAS, Novosibirsk, Russia K. Furukawa, N. Iida, F. Miyahara, K. Oide KEK, Ibaraki, Japan
	The Future Circular Collider-ee aims to get high luminosity which mainly relies upon high charge and low geometric emittance in the collider. The FCC-ee is a future project of CERN to operate as Z, W, H and tt factories with varying energies between 45.6 to 175 GeV. Among those, the total charge requirement is peaked for Z-operation (i.e. 91500 bunches of electron and positron with 3.3·10¹⁰ particles per bunch) meanwhile this mode targets the smallest geometric emittance in the Collider. To reach the goal, the normal conducting S-band Linac has been designed to accelerate 4·10¹⁰ particles in a bunch to 6 GeV and send two bunches per RF pulse within a repetition of 100 Hz. The FCC-ee positrons will also be created inside the linac at 4.46 GeV and accelerated to 1.54 GeV. These positrons are damped at the designed Damping Ring at that energy, and then transferred back to the Linac to meet the same characteristics of electrons. Therefore, in this paper, we'd like to discuss the transmission and robustness of the Linac and the dynamic aperture of the Damping Ring which has to be large enough to accept the incoming beam and cover the probable shrink due to the misalignments.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-TUT2H5
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TUT3BH2	Optics Correction and Low Emittance Tuning at the Phase 1 commissioning of SuperKEKB	143
	Y. Ohnishi, Y. Funakoshi, H. Koiso, A. Morita, K. Oide, H. Sugimoto KEK, Ibaraki, Japan
	The SuperKEKB collider has finally come to the first commissioning, Phase 1 without the final focus system and before Belle II detector roll-in. In order to accomplish a extremely high luminosity of 8x10³⁵ cm^-2s^-1, the nano-beam scheme is adopted. Since the vertical emittance is one of keys in this scheme, optics corrections for low emittance tuning are applied. The non-interleaved sextupole scheme is utilized in the arc section. Skew quadrupole-like corrector is equipped for each sextupole. These skew quadrupole-like correctors can correct both X-Y coupling and physical vertical dispersions which induce the vertical emittance. Beta function and physical horizontal dispersion are corrected by fudge factors of quadrupoles and/or horizontal orbit bumps at the sextupoles. Overall optics performance as well as the strategy of low emittance tuning is also presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-TUT3BH2
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TUT3BH4	Coupling and Dispersion Correction for the Tolerance Study in FCC-ee	151
	S. Aumon, A. Doblhammer, B. Härer, B.J. Holzer CERN, Geneva, Switzerland B. Härer KIT, Karlsruhe, Germany K. Oide KEK, Ibaraki, Japan
	The FCC-ee study is investigating the design of a 100 km e⁺/e⁻ circular collider for precision measurements and rare decay observations in the range of 90 to 350 GeV center of mass energy with luminosities in the order of 10³⁵ cm^-2s^-1. In order to reach such performances, an extreme focusing of the beam is required in the interaction regions with a low vertical beta function of 2 mm at the IP. Moreover, the FCC-ee physics program requires very low emittances never achieved in a collider with 1.3 nm for ε_x and 2 pm for ε_y at 175~GeV, reducing the coupling ratio to around 2/1000. With such requirements, any field errors and sources of coupling will introduce spurious vertical dispersion which degrades emittances, limiting the luminosity of the machine. This study describes the status of the tolerance study and the impact of errors that will affect the vertical emittance. In order to preserve the FCC-ee performances, in particular ε_y, a challenging correction scheme based on dispersion free steering and linear coupling correction is proposed to keep the coupling and the vertical emittance as low as possible.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-TUT3BH4
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WET3AH3	Extraction Line and Beam Dump for the Future Electron Positron Circular Collider	188
	A. Apyan ANSL, Yerevan, Armenia K. Oide KEK, Ibaraki, Japan F. Zimmermann CERN, Geneva, Switzerland
	The conceptual design of an extraction line and beam dump for the future electron positron circular collider is presented. The proposed extraction line, consisting of abort kicker system, spoilers and beam diagnostics apparatus transports the electron and positron beams to the main beam dumps. The beam must be spread over a large surface in order not to damage the beam dump and the window, which separates the ring from the dump. The extraction line redistributes bunches at different locations on the face of beam dump. Monte Carlo simulations using FLUKA have been performed to estimate the distribution of energy deposition on the window and beam dump to find the optimal absorber and its dimensions.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-WET3AH3
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THS1H2	Summary of Optics Issues	199
	K. Oide KEK, Ibaraki, Japan
	Summary of Optics Issues
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-THS1H2
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Paper

Title

Page

Overview of High Energy e⁺e⁻ Factories

1

K. Oide
KEK, Ibaraki, Japan

Designs of e⁺e⁻ colliders from the Z-pole and above are introduced. Two projects, CEPC and FCC-ee, are discussed. If we compare their schemes, a partial double ring (CEPC) and a full double ring (FCC-ee), find several important differences that affect the performance. On the other hand, there are a number of similarities in both designs, such as the crab-waist scheme, crossing angle, optimization of the dynamic aperture, etc.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-MOOTH1

Export •

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

TUT2H5

Towards a Preliminary FCC-ee Injector Design

90

S. Ogur, Y. Papaphilippou, F. Zimmermann
CERN, Geneva, Switzerland
A.M. Barnyakov, A.E. Levichev, D.A. Nikiforov
BINP SB RAS, Novosibirsk, Russia
K. Furukawa, N. Iida, F. Miyahara, K. Oide
KEK, Ibaraki, Japan

The Future Circular Collider-ee aims to get high luminosity which mainly relies upon high charge and low geometric emittance in the collider. The FCC-ee is a future project of CERN to operate as Z, W, H and tt factories with varying energies between 45.6 to 175 GeV. Among those, the total charge requirement is peaked for Z-operation (i.e. 91500 bunches of electron and positron with 3.3·10¹⁰ particles per bunch) meanwhile this mode targets the smallest geometric emittance in the Collider. To reach the goal, the normal conducting S-band Linac has been designed to accelerate 4·10¹⁰ particles in a bunch to 6 GeV and send two bunches per RF pulse within a repetition of 100 Hz. The FCC-ee positrons will also be created inside the linac at 4.46 GeV and accelerated to 1.54 GeV. These positrons are damped at the designed Damping Ring at that energy, and then transferred back to the Linac to meet the same characteristics of electrons. Therefore, in this paper, we'd like to discuss the transmission and robustness of the Linac and the dynamic aperture of the Damping Ring which has to be large enough to accept the incoming beam and cover the probable shrink due to the misalignments.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-TUT2H5

Export •

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

TUT3BH2

Optics Correction and Low Emittance Tuning at the Phase 1 commissioning of SuperKEKB

143

Y. Ohnishi, Y. Funakoshi, H. Koiso, A. Morita, K. Oide, H. Sugimoto
KEK, Ibaraki, Japan

The SuperKEKB collider has finally come to the first commissioning, Phase 1 without the final focus system and before Belle II detector roll-in. In order to accomplish a extremely high luminosity of 8x10³⁵ cm^-2s^-1, the nano-beam scheme is adopted. Since the vertical emittance is one of keys in this scheme, optics corrections for low emittance tuning are applied. The non-interleaved sextupole scheme is utilized in the arc section. Skew quadrupole-like corrector is equipped for each sextupole. These skew quadrupole-like correctors can correct both X-Y coupling and physical vertical dispersions which induce the vertical emittance. Beta function and physical horizontal dispersion are corrected by fudge factors of quadrupoles and/or horizontal orbit bumps at the sextupoles. Overall optics performance as well as the strategy of low emittance tuning is also presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-TUT3BH2

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

TUT3BH4

Coupling and Dispersion Correction for the Tolerance Study in FCC-ee

151

S. Aumon, A. Doblhammer, B. Härer, B.J. Holzer
CERN, Geneva, Switzerland
B. Härer
KIT, Karlsruhe, Germany
K. Oide
KEK, Ibaraki, Japan

The FCC-ee study is investigating the design of a 100 km e⁺/e⁻ circular collider for precision measurements and rare decay observations in the range of 90 to 350 GeV center of mass energy with luminosities in the order of 10³⁵ cm^-2s^-1. In order to reach such performances, an extreme focusing of the beam is required in the interaction regions with a low vertical beta function of 2 mm at the IP. Moreover, the FCC-ee physics program requires very low emittances never achieved in a collider with 1.3 nm for ε_x and 2 pm for ε_y at 175~GeV, reducing the coupling ratio to around 2/1000. With such requirements, any field errors and sources of coupling will introduce spurious vertical dispersion which degrades emittances, limiting the luminosity of the machine. This study describes the status of the tolerance study and the impact of errors that will affect the vertical emittance. In order to preserve the FCC-ee performances, in particular ε_y, a challenging correction scheme based on dispersion free steering and linear coupling correction is proposed to keep the coupling and the vertical emittance as low as possible.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-TUT3BH4

Export •

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

WET3AH3

Extraction Line and Beam Dump for the Future Electron Positron Circular Collider

188

A. Apyan
ANSL, Yerevan, Armenia
K. Oide
KEK, Ibaraki, Japan
F. Zimmermann
CERN, Geneva, Switzerland

The conceptual design of an extraction line and beam dump for the future electron positron circular collider is presented. The proposed extraction line, consisting of abort kicker system, spoilers and beam diagnostics apparatus transports the electron and positron beams to the main beam dumps. The beam must be spread over a large surface in order not to damage the beam dump and the window, which separates the ring from the dump. The extraction line redistributes bunches at different locations on the face of beam dump. Monte Carlo simulations using FLUKA have been performed to estimate the distribution of energy deposition on the window and beam dump to find the optimal absorber and its dimensions.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-WET3AH3

Export •

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

THS1H2

Summary of Optics Issues

199

K. Oide
KEK, Ibaraki, Japan

Summary of Optics Issues

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-eeFACT2016-THS1H2

Export •

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