IPAC2012 - List of Authors (Boldt, O.)

Paper	Title	Page
TUPPC067	How to Achieve Longitudinally Polarized Electrons using Integer Spin Tune Resonances	1326
	O. Boldt, A. Dieckmann, F. Frommberger, W. Hillert, J.F. Schmidt ELSA, Bonn, Germany
	Funding: Bundesministerium für Bildung und Forschung Commonly, strong solenoids are used in circular accelerators to achieve longitudinal polarization. In practice, however, these solenoids cause a phase space coupling, which has to be compensated for by sophisticated decoupling schemes. We suggest to adiabatically ramp into an integer spin tune resonance, while preserving the degree of polarization. When appropriately adjusting the driving horizontal field contributions at the final energy, the resulting polarization is longitudinal at predefined positions in the accelerator. Here, depending on the energy spread, the degree of polarization is conserved for several seconds. The contribution shows the numerical analysis of this scenario being confirmed by first demonstration tests at the ELSA stretcher ring.

THPPD050	Fast Ramping Arbitrary Waveform Power Supplies for Correction Coils in a Circular Electron Accelerator	3623
	A. Dieckmann, A. Balling, O. Boldt, F. Frommberger, W. Hillert, W. Lindenberg ELSA, Bonn, Germany
	New fast ramping power supplies working in pulsed bridge technology upgrade the existing Corrector System at ELSA. Current changes of ±0.8 A/msec are achieved. The newly developed CAN-Bus Interface allows linear interpolation of up to 250 support points with minimal time steps of 1msec. The first stage uses 24 power supplies to improve the position of the beam orbit in the horizontal plane using dipole correction coils. It will be extended to include the vertical plane with new corrector coils in the near future. This poster describes the operating principles of the power supply and the interface.

Paper

Title

Page

How to Achieve Longitudinally Polarized Electrons using Integer Spin Tune Resonances

1326

O. Boldt, A. Dieckmann, F. Frommberger, W. Hillert, J.F. Schmidt
ELSA, Bonn, Germany

Funding: Bundesministerium für Bildung und Forschung
Commonly, strong solenoids are used in circular accelerators to achieve longitudinal polarization. In practice, however, these solenoids cause a phase space coupling, which has to be compensated for by sophisticated decoupling schemes. We suggest to adiabatically ramp into an integer spin tune resonance, while preserving the degree of polarization. When appropriately adjusting the driving horizontal field contributions at the final energy, the resulting polarization is longitudinal at predefined positions in the accelerator. Here, depending on the energy spread, the degree of polarization is conserved for several seconds. The contribution shows the numerical analysis of this scenario being confirmed by first demonstration tests at the ELSA stretcher ring.

THPPD050

Fast Ramping Arbitrary Waveform Power Supplies for Correction Coils in a Circular Electron Accelerator

3623

A. Dieckmann, A. Balling, O. Boldt, F. Frommberger, W. Hillert, W. Lindenberg
ELSA, Bonn, Germany

New fast ramping power supplies working in pulsed bridge technology upgrade the existing Corrector System at ELSA. Current changes of ±0.8 A/msec are achieved. The newly developed CAN-Bus Interface allows linear interpolation of up to 250 support points with minimal time steps of 1msec. The first stage uses 24 power supplies to improve the position of the beam orbit in the horizontal plane using dipole correction coils. It will be extended to include the vertical plane with new corrector coils in the near future. This poster describes the operating principles of the power supply and the interface.