2011 Particle Accelerator Conference - List of Authors (Burov, A.V.)

Paper

Title

Page

Dancing Bunches as van Kampen Modes

94

A.V. Burov
Fermilab, Batavia, USA

Theory of van Kampen modes is applied to bunch longitudinal motion. Case of inductive impedance domination is studied in more details. Threshold for loss of Landau damping is found to be very sensitive to fine structure of the distribution function. Good agreement with the Tevatron's "dancing bunches" is obtained.

Slides MOODS4 [0.408 MB]

WEP114

Transverse Instability of the Antiproton Beam In the Recycler Ring

1698

L.R. Prost, C.M. Bhat, A.V. Burov, J.L. Crisp, N. Eddy, M. Hu, A.V. Shemyakin
Fermilab, Batavia, USA

Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The brightness of the antiproton beam in Fermilab’s 8 GeV Recycler ring is limited by a transverse instability. This instability has occurred during the extraction process to the Tevatron for large stacks of antiprotons even with dampers in operation. This paper describes observed features of the instability, introduces the threshold phase density to characterize the beam stability, and finds the results to be in agreement with a resistive wall instability model. Effective exclusion of the longitudinal tails from Landau damping by decreasing the depth of the RF potential well is observed to lower the threshold density by up to a factor of two.

WEP116

Bucket Shaking Stops Bunch Dancing in Tevatron

1704

A.V. Burov, C.-Y. Tan
Fermilab, Batavia, USA

Bunches in Tevatron are known to be longitudinally unstable: their collective oscillations stay without any sign of decay. Typically, a feedback damper is used to stop these oscillations. Recently, it was theoretically predicted that the oscillations can be stabilized by means of small bucket shaking*. Detailed measurements in Tevatron have shown that this method does work. In this paper, an essential theory and specific observations of the related process are presented.
* A. Burov, “Dancing Bunches as van Kampen Modes”, this conference.

Paper	Title	Page
MOODS4	Dancing Bunches as van Kampen Modes	94
	A.V. Burov Fermilab, Batavia, USA
	Theory of van Kampen modes is applied to bunch longitudinal motion. Case of inductive impedance domination is studied in more details. Threshold for loss of Landau damping is found to be very sensitive to fine structure of the distribution function. Good agreement with the Tevatron's "dancing bunches" is obtained.
	Slides MOODS4 [0.408 MB]

WEP114	Transverse Instability of the Antiproton Beam In the Recycler Ring	1698
	L.R. Prost, C.M. Bhat, A.V. Burov, J.L. Crisp, N. Eddy, M. Hu, A.V. Shemyakin Fermilab, Batavia, USA
	Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. The brightness of the antiproton beam in Fermilab’s 8 GeV Recycler ring is limited by a transverse instability. This instability has occurred during the extraction process to the Tevatron for large stacks of antiprotons even with dampers in operation. This paper describes observed features of the instability, introduces the threshold phase density to characterize the beam stability, and finds the results to be in agreement with a resistive wall instability model. Effective exclusion of the longitudinal tails from Landau damping by decreasing the depth of the RF potential well is observed to lower the threshold density by up to a factor of two.

WEP116	Bucket Shaking Stops Bunch Dancing in Tevatron	1704
	A.V. Burov, C.-Y. Tan Fermilab, Batavia, USA
	Bunches in Tevatron are known to be longitudinally unstable: their collective oscillations stay without any sign of decay. Typically, a feedback damper is used to stop these oscillations. Recently, it was theoretically predicted that the oscillations can be stabilized by means of small bucket shaking. Detailed measurements in Tevatron have shown that this method does work. In this paper, an essential theory and specific observations of the related process are presented. A. Burov, “Dancing Bunches as van Kampen Modes”, this conference.