LINAC2014 - List of Authors (Xiao, C.)

Paper

Title

Page

Single-Knob Beam Line for Transverse Emittance Partitioning

36

C. Xiao, L. Groening, O.K. Kester, H. Leibrock, M.T. Maier, P. Rottländer
GSI, Darmstadt, Germany
M. Chung
UNIST, Ulsan, Republic of Korea

Flat beams feature unequal emittances in the horizontal and vertical phase space. Such beams were created successfully in electron machines by applying effective stand-alone solenoid fringe fields in the electron gun. Extension of this method to ion beams was proposed conceptually. The present paper is on the decoupling capabilities of an ion beam emittance transfer line. The proposed beam line provides a single-knob tool to partition the horizontal and vertical rms emittances, while keeping the product of the two emittances constant as well as the transverse rms Twiss parameters (αx,y and βx,y) in both planes. It is shown that this single knob is the solenoid field strength, and now we fully understand the decoupling features.

Slides MOIOC02 [1.327 MB]

MOPP060

Status of the GSI Poststripper - HE-Linac

190

S. Mickat, W.A. Barth, G. Clemente, X. Du, L. Groening, A. Orzhekhovskaya, B. Schlitt, H. Vormann, C. Xiao, S.G. Yaramyshev
GSI, Darmstadt, Germany
M. Droba, H. Hähnel, U. Ratzinger, R. Tiede
IAP, Frankfurt am Main, Germany

The High-Energy (HE) Linac is proposed to substitute the existing UNILAC post-stripper section. The post-stripper is an Alvarez DTL, which is in operation over four decades successfully. A quasi Front-to-End simulation along the UNILAC shows, that by taking future upgrade options into account already, with the existing Alvarez section the Fair requirements are not reached. Even by substituting the Alvarez section by the HE Linac the aim is not reached per se regarding the existing boundary conditions. Currently workpackages are defined together with the Institute of Applied Physics at Frankfurt University. Starting from the Ion sources to the SIS18 transfer channel every section is reinvestigated for improvements in beam quality and intensity.

THPP065

Acceleration of Intense Flat Beams in Periodic Lattices

1001

L. Groening, C. Xiao
GSI, Darmstadt, Germany
I. Hofmann
TEMF, TU Darmstadt, Darmstadt, Germany

Recently a scheme for creation of flat ion beams from linacs has been proposed to increase the efficiency of multi-turn-injection. The proof of principle experiment shall be performed at GSI in Summer 2014. Since the scheme requires charge stripping, it may be necessary to perform the round-to-flat transformation prior to acceleration to the final energy of the linac. This requires preservation of the beam flatness during acceleration along the drift tube linac. This contribution is on simulations of acceleration of flat beams subject to considerable space charge tune depression. It is shown that the flatness can be preserved if the transverse tunes are properly chosen and if mis-match along inter-tank sections is minimized along the DTL.

Paper	Title	Page
MOIOC02	Single-Knob Beam Line for Transverse Emittance Partitioning	36
	C. Xiao, L. Groening, O.K. Kester, H. Leibrock, M.T. Maier, P. Rottländer GSI, Darmstadt, Germany M. Chung UNIST, Ulsan, Republic of Korea
	Flat beams feature unequal emittances in the horizontal and vertical phase space. Such beams were created successfully in electron machines by applying effective stand-alone solenoid fringe fields in the electron gun. Extension of this method to ion beams was proposed conceptually. The present paper is on the decoupling capabilities of an ion beam emittance transfer line. The proposed beam line provides a single-knob tool to partition the horizontal and vertical rms emittances, while keeping the product of the two emittances constant as well as the transverse rms Twiss parameters (αx,y and βx,y) in both planes. It is shown that this single knob is the solenoid field strength, and now we fully understand the decoupling features.
	Slides MOIOC02 [1.327 MB]

MOPP060	Status of the GSI Poststripper - HE-Linac	190
	S. Mickat, W.A. Barth, G. Clemente, X. Du, L. Groening, A. Orzhekhovskaya, B. Schlitt, H. Vormann, C. Xiao, S.G. Yaramyshev GSI, Darmstadt, Germany M. Droba, H. Hähnel, U. Ratzinger, R. Tiede IAP, Frankfurt am Main, Germany
	The High-Energy (HE) Linac is proposed to substitute the existing UNILAC post-stripper section. The post-stripper is an Alvarez DTL, which is in operation over four decades successfully. A quasi Front-to-End simulation along the UNILAC shows, that by taking future upgrade options into account already, with the existing Alvarez section the Fair requirements are not reached. Even by substituting the Alvarez section by the HE Linac the aim is not reached per se regarding the existing boundary conditions. Currently workpackages are defined together with the Institute of Applied Physics at Frankfurt University. Starting from the Ion sources to the SIS18 transfer channel every section is reinvestigated for improvements in beam quality and intensity.

THPP065	Acceleration of Intense Flat Beams in Periodic Lattices	1001
	L. Groening, C. Xiao GSI, Darmstadt, Germany I. Hofmann TEMF, TU Darmstadt, Darmstadt, Germany
	Recently a scheme for creation of flat ion beams from linacs has been proposed to increase the efficiency of multi-turn-injection. The proof of principle experiment shall be performed at GSI in Summer 2014. Since the scheme requires charge stripping, it may be necessary to perform the round-to-flat transformation prior to acceleration to the final energy of the linac. This requires preservation of the beam flatness during acceleration along the drift tube linac. This contribution is on simulations of acceleration of flat beams subject to considerable space charge tune depression. It is shown that the flatness can be preserved if the transverse tunes are properly chosen and if mis-match along inter-tank sections is minimized along the DTL.