Topical Workshop on Instabilities, Impedance and Collective Effects 2014 (TWIICE2014)

Session

Impedances and Instabilities

6

16 Jan 2014, 09:00

Synchrotron SOLEIL

Description

Chairman: John BYRD (LBNL)

6. Theory of Beam Transverse Instabilities

Alexey Burov (Fermi National Accelerator Lab. (US))

16/01/2014, 09:00

(Review) Main theoretical aspects of beam transverse instabilities in low-emittance rings are successively considered. First, coherent tune shifts are found with the nested head-tail method for arbitrary longitudinal distribution and single and coupled bunches, and with a feedback damper taken into account. Then, the transverse nonlinearity is included, and Landau damping is analyzed by means...

27. Impedance and collective effects in Beijing Advanced Photon Source

Na WANG (BAPS)

16/01/2014, 09:35

Beijing Advanced Photon Source (BAPS) is a 5GeV storage ring-based light source. Due to the low emittance and high beam current, the collective effects may bring new challenges to the physical design of the machine. A thorough evaluation of the coupling impedance is necessary in controlling the total impedance of the ring, which can accordingly prevent the occurrence of the beam instability....

8. Evaluation of Collective Effects for the ESRF Upgrade Project

Thomas Perron (ESRF)

16/01/2014, 09:55

A project to fully rebuild the main ring in the existing tunnel is underway at the ESRF. A preliminary analysis of the collective effects we may face operating this new machine will be presented. Current thresholds will be evaluated extrapolating data collected on the actual ESRF. Beam emittance growth including bunch lengthening and intra- beam scattering will also be discussed.

28. High frequency effects of impedance and coatings in the CLIC damping rings

Eirini Koukovini Platia (Ecole Polytechnique Federale de Lausanne (CH))

16/01/2014, 10:15

Single bunch instability thresholds and the associated coherent tune shifts have been evaluated in the transverse plane for the damping rings (DR) of the Compact Linear Collider (CLIC). A multi-kick version of the HEADTAIL code was used to study the instability thresholds in the case where different impedance contributions are taken into account such as the broad-band resonator model in...