HB2014 - List of Authors (Kester, O.K.)

Paper

Title

Page

Space-Charge Compensation of Intense Ion Beams by Nonneutral Plasma Columns

67

K. Schulte, M. Droba, O.K. Kester, S. Klaproth, O. Meusel, D. Noll, U. Ratzinger, K. Zerbe
IAP, Frankfurt am Main, Germany
O.K. Kester
GSI, Darmstadt, Germany

Gabor lenses were conceived to focus a passing ion beam using the electrical field of a confined nonneutral plasma column. Beside its application as focusing device, in Gabor lenses space-charge effects can be studied in detail. The influence of the electron distribution on emittance and space-charge dominated ion beams was investigated in beam transport experiments*. In this contribution we want to emphasize one result of these experiments. The measurements indicated a strong contribution of secondary electrons on beam dynamics. Secondary electrons are produced within the transport channel, particularly by interaction of the beam with the surface of the slit-grid emittance scanner. This might lead to an increase of the filling degree and to an improved focusing performance of the lens. Assuming that the loss and production rates within the lens volume and the transport channel determine the equilibrium state of the nonneutral plasma column, the electron cloud was characterized as a function of the external fields and the residual gas pressure in small-scale table top experiments. In this contribution experimental results will be presented in comparison with numerical simulations.
* K. Schulte, “Studies on the focusing performance of a Gabor lens depending on nonneutral plasma properties”, PhD thesis, 2013.

WEO3LR04

Emittance Transfer in Linacs

289

L. Groening, M.T. Maier, C. Xiao
GSI, Darmstadt, Germany
O.K. Kester
IAP, Frankfurt am Main, Germany

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. This contribution is an extension of the method to ion beams and on the decoupling capabilities of such a round-to-flat adaptor. The 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 (beta_x;y and alpha_x;y) in both planes. This single knob is the solenoid field strength. The successful commissioning of the set-up with beam will be presented as well.

Slides WEO3LR04 [1.289 MB]

Paper	Title	Page
MOPAB19	Space-Charge Compensation of Intense Ion Beams by Nonneutral Plasma Columns	67
	K. Schulte, M. Droba, O.K. Kester, S. Klaproth, O. Meusel, D. Noll, U. Ratzinger, K. Zerbe IAP, Frankfurt am Main, Germany O.K. Kester GSI, Darmstadt, Germany
	Gabor lenses were conceived to focus a passing ion beam using the electrical field of a confined nonneutral plasma column. Beside its application as focusing device, in Gabor lenses space-charge effects can be studied in detail. The influence of the electron distribution on emittance and space-charge dominated ion beams was investigated in beam transport experiments. In this contribution we want to emphasize one result of these experiments. The measurements indicated a strong contribution of secondary electrons on beam dynamics. Secondary electrons are produced within the transport channel, particularly by interaction of the beam with the surface of the slit-grid emittance scanner. This might lead to an increase of the filling degree and to an improved focusing performance of the lens. Assuming that the loss and production rates within the lens volume and the transport channel determine the equilibrium state of the nonneutral plasma column, the electron cloud was characterized as a function of the external fields and the residual gas pressure in small-scale table top experiments. In this contribution experimental results will be presented in comparison with numerical simulations. K. Schulte, “Studies on the focusing performance of a Gabor lens depending on nonneutral plasma properties”, PhD thesis, 2013.

WEO3LR04	Emittance Transfer in Linacs	289
	L. Groening, M.T. Maier, C. Xiao GSI, Darmstadt, Germany O.K. Kester IAP, Frankfurt am Main, Germany
	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. This contribution is an extension of the method to ion beams and on the decoupling capabilities of such a round-to-flat adaptor. The 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 (beta_x;y and alpha_x;y) in both planes. This single knob is the solenoid field strength. The successful commissioning of the set-up with beam will be presented as well.
	Slides WEO3LR04 [1.289 MB]