IPAC2012 - List of Authors (Franchetti, G.)

Paper	Title	Page
WEPPR011	Numerical Simulation Study of the Montague Resonance at the CERN Proton Synchrotron	2958
	J. Qiang, R.D. Ryne LBNL, Berkeley, California, USA G. Franchetti, I. Hofmann GSI, Darmstadt, Germany E. Métral CERN, Geneva, Switzerland
	Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP) under Contract No. DE-AC02-05CH11231. The Montague resonance provides a coupling between the vertical and the horizontal dynamics of beams and can cause particle losses due to unequal aperture sizes of the accelerator. In this paper, we present a new numerical simulation study of a previous Montague resonance crossing experiment at the CERN PS including detailed three-dimensional space-charge effects and machine nonlinearity. The simulation reproduces the experimental data and suggests that the longitudinal synchrotron motion played an important role in enhancing transverse resonance coupling.

WEPPR047	The Effect of Non-Zero Closed Orbit on Electron-Cloud Pinch Dynamics	3033
	G. Franchetti GSI, Darmstadt, Germany F. Zimmermann CERN, Geneva, Switzerland
	A study on the pinch dynamics of electron cloud during a bunch passage under the effect of a single arbitrary-order multipole was presented at IPAC2011. The complexity of the pinch pattern is directly related to the order of the multipolar field. However, in a realistic situation, the proton beam will not be located in the center of the vacuum chamber. If the beam is offset a new pinch regime is encountered, where feed-down effects and asymmetry of pinch density render the dynamics more challenging. In this paper we discuss the pinch dynamics with orbit offset, including the resulting orbit variation along a bunch, and address their relevance for the incoherent effect of the electron cloud.

Paper

Title

Page

Numerical Simulation Study of the Montague Resonance at the CERN Proton Synchrotron

2958

J. Qiang, R.D. Ryne
LBNL, Berkeley, California, USA
G. Franchetti, I. Hofmann
GSI, Darmstadt, Germany
E. Métral
CERN, Geneva, Switzerland

Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP) under Contract No. DE-AC02-05CH11231.
The Montague resonance provides a coupling between the vertical and the horizontal dynamics of beams and can cause particle losses due to unequal aperture sizes of the accelerator. In this paper, we present a new numerical simulation study of a previous Montague resonance crossing experiment at the CERN PS including detailed three-dimensional space-charge effects and machine nonlinearity. The simulation reproduces the experimental data and suggests that the longitudinal synchrotron motion played an important role in enhancing transverse resonance coupling.

WEPPR047

The Effect of Non-Zero Closed Orbit on Electron-Cloud Pinch Dynamics

3033

G. Franchetti
GSI, Darmstadt, Germany
F. Zimmermann
CERN, Geneva, Switzerland

A study on the pinch dynamics of electron cloud during a bunch passage under the effect of a single arbitrary-order multipole was presented at IPAC2011. The complexity of the pinch pattern is directly related to the order of the multipolar field. However, in a realistic situation, the proton beam will not be located in the center of the vacuum chamber. If the beam is offset a new pinch regime is encountered, where feed-down effects and asymmetry of pinch density render the dynamics more challenging. In this paper we discuss the pinch dynamics with orbit offset, including the resulting orbit variation along a bunch, and address their relevance for the incoherent effect of the electron cloud.