IPAC2011 - List of Authors (Zhang, Y.)

Paper	Title	Page
MOPS003	Coherent Beam-beam Resonances in SuperB with Asymmetric Rings	592
	M. Zobov INFN/LNF, Frascati (Roma), Italy Y. Zhang IHEP Beijing, Beijing, People's Republic of China
	One of the latest options of SuperB foresees exploiting rings with unequal circumferences. In such a configuration additional coherent beam-beam resonances can arise. In this paper we discuss the possible impact of the resonances on beam dynamics in SuperB, maximum achievable tune shifts and working point choice.

TUPC107	Some Preliminary Experiments using LIBERA BPMs in BEPCII*	1266
	Y. Zhang, H.Z. Ma, J. Yue IHEP Beijing, Beijing, People's Republic of China
	Funding: Supported by the National Natural Science Foundation of China (10805051) There are total 16 LIBERA BPMs in BEPCII, which is a double ring e⁺e⁻ collider. The turn-by-turn BPMs serve as only tune measurement system in most cases during normal operation. We tried to do some more machine study using them: the local coupling parameter at the BPM, the resonance driving term, the decoherence parameter which could be used to calibrate the strength of octupole in the ring. We also compare the difference from the different exciting method: single time kick with injection kicker or sinusoidal kick with feedback system.

THPZ003	The SuperB Project: Accelerator Status and R&D	3684
	M.E. Biagini, S. Bini, R. Boni, M. Boscolo, B. Buonomo, T. Demma, E. Di Pasquale, A. Drago, L.G. Foggetta, S. Guiducci, S.M. Liuzzo, G. Mazzitelli, L. Pellegrino, M.A. Preger, P. Raimondi, U. Rotundo, C. Sanelli, M. Serio, A. Stecchi, A. Stella, S. Tomassini, M. Zobov INFN/LNF, Frascati (Roma), Italy M.A. Baylac, O. Bourrion, J.-M. De Conto, N. Monseu, C. Vescovi LPSC, Grenoble, France K.J. Bertsche, A. Brachmann, Y. Cai, A. Chao, M.H. Donald, R.C. Field, A.S. Fisher, D. Kharakh, A. Krasnykh, K.C. Moffeit, Y. Nosochkov, A. Novokhatski, M.T.F. Pivi, J.T. Seeman, M.K. Sullivan, S.P. Weathersby, A.W. Weidemann, U. Wienands, W. Wittmer, G. Yocky SLAC, Menlo Park, California, USA S. Bettoni PSI, Villigen, Switzerland A.V. Bogomyagkov, I. Koop, E.B. Levichev, S.A. Nikitin, I.N. Okunev, P.A. Piminov, D.N. Shatilov, S.V. Sinyatkin, P. Vobly BINP SB RAS, Novosibirsk, Russia B. Bolzon, M. Esposito CERN, Geneva, Switzerland F. Bosi INFN-Pisa, Pisa, Italy L. Brunetti, A. Jeremie IN2P3-LAPP, Annecy-le-Vieux, France A. Chancé CEA, Gif-sur-Yvette, France P. Fabbricatore, S. Farinon, R. Musenich INFN Genova, Genova, Italy E. Paoloni University of Pisa and INFN, Pisa, Italy C. Rimbault, A. Variola LAL, Orsay, France Y. Zhang IHEP Beijing, Beijing, People's Republic of China
	The SuperB collider project has been recently approved by the Italian Government as part of the National Research Plan. SuperB is a high luminosity (10³6 cm^-2 s^-1) asymmetric e⁺e⁻ collider at the Y(4S) energy. The design is based on a “large Piwinski angle and Crab Waist” scheme already successfully tested at the DAΦNE Phi-Factory in Frascati, Italy. The project combines the challenges of high luminosity colliders and state-of-the-art synchrotron light sources, with two beams (e⁺ at 6.7 and e^- at 4.2 GeV) with extremely low emittances and small beam sizes at the Interaction Point. As unique features, the electron beam will be longitudinally polarized at the IP and the rings will be able to ramp down to collide at the tau/charm energy threshold with one tenth the luminosity. The relatively low beam currents (about 2 A) will allow for low running (power) costs compared to similar machines. The insertion of beam lines for synchrotron radiation users is the latest feature included in the design. The lattice has been recently modified to accommodate insertion devices for X-rays production. A status of the project and a description of R&D in progress will be presented.

THPZ012	Luminosity Enhancement and Performance in BEPCII	3708
	Q. Qin, J. Cao, J. Cheng, Y.L. Chi, H. Dong, Z. Duan, D. Ji, W. Kang, S.P. Li, L. Ma, H. Qu, C.H. Wang, G.W. Wang, J.Q. Wang, X.H. Wang, Y. Wei, J. Xing, G. Xu, C.H. Yu, J. Yue, C. Zhang, Y. Zhang IHEP Beijing, Beijing, People's Republic of China
	The Beijing Electron Positron Collider (BEPC) was upgraded to a factory-like machine –- BEPCII, during last several years. From last November, the BEPCII was commissioned again for its luminosity. Efforts on optics correction including optimizing the strengths of superconducting quadrupoles near the IP, orbits correction concerning beam energy, etc, make the transvers tunes possible to move very close to half integer, bringing a big luminosity increase. The background of the detector is also reduced with beam commissioning, and finally fit the requirements of data taking. Further luminosity commissioing, including coupling optimization, beta-waist tuning, was carried on, and the luminosity reached 6.49·10³² cm^-2 s^-1 during routine operation. Some measures of luminosity enhancement and the luminosity related accelerator physics issues will be discussed.

WEPC047	Crab Crossing Schemes and Studies for Electron Ion Collider	2115
	S. Ahmed, S.U. De Silva, Y.S. Derbenev, G.A. Krafft, V.S. Morozov, B.C. Yunn, Y. Zhang JLAB, Newport News, Virginia, USA A. Castilla, J.R. Delayen ODU, Norfolk, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Medium Energy Electron Ion Collider (MEIC) at JLab has been envisioned as future high energy particle accelerator beyond 12 GeV upgrade of CEBAF. Crab crossing of colliding electron and ion beams is essential for accommodating high bunch repetition frequency in the conceptual design of MEIC. The scheme eliminates parasitic beam-beam interactions and avoids luminosity reduction by restoring head-on collisions at interaction points. This requires the separation of two beams quickly to avoid parasitic collisions and the minimization of synchrotron-betatron resonance near IP which can be fulfilled by employing the crab crossing concept first proposed by R. Palmer. Let us call this original scheme as transverse crabbing for the sake of comparison with dispersive crabbing which employs the existing accelerating/bunching RF cavities and dispersion function in the section where the cavity is installed as originally proposed by G. Jackson. In this paper, we report the beam transport and optics for both transverse and dispersive crabbing schemes followed by basic beam dynamics. Moreover, alignment and stability calculations together with synchro-betatron beam dynamics will be discussed.

Paper

Title

Page

Coherent Beam-beam Resonances in SuperB with Asymmetric Rings

592

M. Zobov
INFN/LNF, Frascati (Roma), Italy
Y. Zhang
IHEP Beijing, Beijing, People's Republic of China

One of the latest options of SuperB foresees exploiting rings with unequal circumferences. In such a configuration additional coherent beam-beam resonances can arise. In this paper we discuss the possible impact of the resonances on beam dynamics in SuperB, maximum achievable tune shifts and working point choice.

TUPC107

Some Preliminary Experiments using LIBERA BPMs in BEPCII*

1266

Y. Zhang, H.Z. Ma, J. Yue
IHEP Beijing, Beijing, People's Republic of China

Funding: Supported by the National Natural Science Foundation of China (10805051)
There are total 16 LIBERA BPMs in BEPCII, which is a double ring e⁺e⁻ collider. The turn-by-turn BPMs serve as only tune measurement system in most cases during normal operation. We tried to do some more machine study using them: the local coupling parameter at the BPM, the resonance driving term, the decoherence parameter which could be used to calibrate the strength of octupole in the ring. We also compare the difference from the different exciting method: single time kick with injection kicker or sinusoidal kick with feedback system.

THPZ003

The SuperB Project: Accelerator Status and R&D

3684

M.E. Biagini, S. Bini, R. Boni, M. Boscolo, B. Buonomo, T. Demma, E. Di Pasquale, A. Drago, L.G. Foggetta, S. Guiducci, S.M. Liuzzo, G. Mazzitelli, L. Pellegrino, M.A. Preger, P. Raimondi, U. Rotundo, C. Sanelli, M. Serio, A. Stecchi, A. Stella, S. Tomassini, M. Zobov
INFN/LNF, Frascati (Roma), Italy
M.A. Baylac, O. Bourrion, J.-M. De Conto, N. Monseu, C. Vescovi
LPSC, Grenoble, France
K.J. Bertsche, A. Brachmann, Y. Cai, A. Chao, M.H. Donald, R.C. Field, A.S. Fisher, D. Kharakh, A. Krasnykh, K.C. Moffeit, Y. Nosochkov, A. Novokhatski, M.T.F. Pivi, J.T. Seeman, M.K. Sullivan, S.P. Weathersby, A.W. Weidemann, U. Wienands, W. Wittmer, G. Yocky
SLAC, Menlo Park, California, USA
S. Bettoni
PSI, Villigen, Switzerland
A.V. Bogomyagkov, I. Koop, E.B. Levichev, S.A. Nikitin, I.N. Okunev, P.A. Piminov, D.N. Shatilov, S.V. Sinyatkin, P. Vobly
BINP SB RAS, Novosibirsk, Russia
B. Bolzon, M. Esposito
CERN, Geneva, Switzerland
F. Bosi
INFN-Pisa, Pisa, Italy
L. Brunetti, A. Jeremie
IN2P3-LAPP, Annecy-le-Vieux, France
A. Chancé
CEA, Gif-sur-Yvette, France
P. Fabbricatore, S. Farinon, R. Musenich
INFN Genova, Genova, Italy
E. Paoloni
University of Pisa and INFN, Pisa, Italy
C. Rimbault, A. Variola
LAL, Orsay, France
Y. Zhang
IHEP Beijing, Beijing, People's Republic of China

The SuperB collider project has been recently approved by the Italian Government as part of the National Research Plan. SuperB is a high luminosity (10³6 cm^-2 s^-1) asymmetric e⁺e⁻ collider at the Y(4S) energy. The design is based on a “large Piwinski angle and Crab Waist” scheme already successfully tested at the DAΦNE Phi-Factory in Frascati, Italy. The project combines the challenges of high luminosity colliders and state-of-the-art synchrotron light sources, with two beams (e⁺ at 6.7 and e^- at 4.2 GeV) with extremely low emittances and small beam sizes at the Interaction Point. As unique features, the electron beam will be longitudinally polarized at the IP and the rings will be able to ramp down to collide at the tau/charm energy threshold with one tenth the luminosity. The relatively low beam currents (about 2 A) will allow for low running (power) costs compared to similar machines. The insertion of beam lines for synchrotron radiation users is the latest feature included in the design. The lattice has been recently modified to accommodate insertion devices for X-rays production. A status of the project and a description of R&D in progress will be presented.

THPZ012

Luminosity Enhancement and Performance in BEPCII

3708

Q. Qin, J. Cao, J. Cheng, Y.L. Chi, H. Dong, Z. Duan, D. Ji, W. Kang, S.P. Li, L. Ma, H. Qu, C.H. Wang, G.W. Wang, J.Q. Wang, X.H. Wang, Y. Wei, J. Xing, G. Xu, C.H. Yu, J. Yue, C. Zhang, Y. Zhang
IHEP Beijing, Beijing, People's Republic of China

The Beijing Electron Positron Collider (BEPC) was upgraded to a factory-like machine –- BEPCII, during last several years. From last November, the BEPCII was commissioned again for its luminosity. Efforts on optics correction including optimizing the strengths of superconducting quadrupoles near the IP, orbits correction concerning beam energy, etc, make the transvers tunes possible to move very close to half integer, bringing a big luminosity increase. The background of the detector is also reduced with beam commissioning, and finally fit the requirements of data taking. Further luminosity commissioing, including coupling optimization, beta-waist tuning, was carried on, and the luminosity reached 6.49·10³² cm^-2 s^-1 during routine operation. Some measures of luminosity enhancement and the luminosity related accelerator physics issues will be discussed.

WEPC047

Crab Crossing Schemes and Studies for Electron Ion Collider

2115

S. Ahmed, S.U. De Silva, Y.S. Derbenev, G.A. Krafft, V.S. Morozov, B.C. Yunn, Y. Zhang
JLAB, Newport News, Virginia, USA
A. Castilla, J.R. Delayen
ODU, Norfolk, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Medium Energy Electron Ion Collider (MEIC) at JLab has been envisioned as future high energy particle accelerator beyond 12 GeV upgrade of CEBAF. Crab crossing of colliding electron and ion beams is essential for accommodating high bunch repetition frequency in the conceptual design of MEIC. The scheme eliminates parasitic beam-beam interactions and avoids luminosity reduction by restoring head-on collisions at interaction points. This requires the separation of two beams quickly to avoid parasitic collisions and the minimization of synchrotron-betatron resonance near IP which can be fulfilled by employing the crab crossing concept first proposed by R. Palmer. Let us call this original scheme as transverse crabbing for the sake of comparison with dispersive crabbing which employs the existing accelerating/bunching RF cavities and dispersion function in the section where the cavity is installed as originally proposed by G. Jackson. In this paper, we report the beam transport and optics for both transverse and dispersive crabbing schemes followed by basic beam dynamics. Moreover, alignment and stability calculations together with synchro-betatron beam dynamics will be discussed.