IPAC2011 - List of Authors (Meller, R.E.)

Paper	Title	Page
MOPS084	Status of Electron Cloud Dynamics Measurements at CESRTA*	799
	M.G. Billing, G. Dugan, M.J. Forster, D.L. Kreinick, R.E. Meller, M.A. Palmer, G. Ramirez, M.C. Rendina, N.T. Rider, J.P. Sikora, K.G. Sonnad, H.A. Williams CLASSE, Ithaca, New York, USA J.Y. Chu CMU, Pittsburgh, Pennsylvania, USA J.W. Flanagan KEK, Ibaraki, Japan R. Holtzapple, M. Randazzo CalPoly, San Luis Obispo, California, USA
	Funding: Supported by US National Science Foundation (PHY-0734867) & Dept. of Energy (DE-FC02-08ER41538) The study of electron cloud-related instabilities for the CESR-TA project permits the observation of the interaction of the electron cloud with the stored beam under a variety of accelerator conditions. These measurements are undertaken utilizing automatic and semi-automatic techniques for three basic observations: the measurement of tune shifts of individual bunches along a train, the detection of the coherent self-excited spectrum for each bunch within a train and the pulsed excitation of either the betatron dipole or head-tail mode for each individual bunch within the train, followed by the observation of the damping of its coherent motion. These techniques are employed to study the electron cloud-related interactions in a number of conditions, such as trains of bunches with low emittance and spaced by as little as 4 nsec between bunches. We report on the most recent observations and results.

MOPS083	Update on Electron Cloud Mitigation Studies at Cesr-TA*	796
	J.R. Calvey, M.G. Billing, J.V. Conway, G. Dugan, S. Greenwald, Y. Li, X. Liu, J.A. Livezey, J. Makita, R.E. Meller, M.A. Palmer, S. Santos, R.M. Schwartz, J.P. Sikora, C.R. Strohman CLASSE, Ithaca, New York, USA S. Calatroni, G. Rumolo CERN, Geneva, Switzerland K. Kanazawa, Y. Suetsugu KEK, Ibaraki, Japan M.T.F. Pivi, L. Wang SLAC, Menlo Park, California, USA
	Funding: Work supported by the US National Science Foundation (PHY-0734867) and Department of Energy (DE-FC02-08ER41538) Over the course of the past three years, the Cornell Electron Storage Ring (CESR) has been reconfigured to serve as a test facility for next generation particle accelerators. A significant part of this program has been the installation of several diagnostic devices to measure and quantify the electron cloud effect, a potential limiting factor in these machines. In particular, more than 30 Retarding Field Analyzers (RFAs) have been installed in CESR. These devices measure the local electron cloud density and energy distribution, and can be used to evaluate the efficacy of different cloud mitigation techniques. This paper will provide an overview of RFA results obtained at CesrTA over the past year, including measurements taken as function of bunch spacing and wiggler magnetic field. Understanding these results provides a great deal of insight into the behavior of the electron cloud.

Paper

Title

Page

Status of Electron Cloud Dynamics Measurements at CESRTA*

799

M.G. Billing, G. Dugan, M.J. Forster, D.L. Kreinick, R.E. Meller, M.A. Palmer, G. Ramirez, M.C. Rendina, N.T. Rider, J.P. Sikora, K.G. Sonnad, H.A. Williams
CLASSE, Ithaca, New York, USA
J.Y. Chu
CMU, Pittsburgh, Pennsylvania, USA
J.W. Flanagan
KEK, Ibaraki, Japan
R. Holtzapple, M. Randazzo
CalPoly, San Luis Obispo, California, USA

Funding: Supported by US National Science Foundation (PHY-0734867) & Dept. of Energy (DE-FC02-08ER41538)
The study of electron cloud-related instabilities for the CESR-TA project permits the observation of the interaction of the electron cloud with the stored beam under a variety of accelerator conditions. These measurements are undertaken utilizing automatic and semi-automatic techniques for three basic observations: the measurement of tune shifts of individual bunches along a train, the detection of the coherent self-excited spectrum for each bunch within a train and the pulsed excitation of either the betatron dipole or head-tail mode for each individual bunch within the train, followed by the observation of the damping of its coherent motion. These techniques are employed to study the electron cloud-related interactions in a number of conditions, such as trains of bunches with low emittance and spaced by as little as 4 nsec between bunches. We report on the most recent observations and results.

MOPS083

Update on Electron Cloud Mitigation Studies at Cesr-TA*

796

J.R. Calvey, M.G. Billing, J.V. Conway, G. Dugan, S. Greenwald, Y. Li, X. Liu, J.A. Livezey, J. Makita, R.E. Meller, M.A. Palmer, S. Santos, R.M. Schwartz, J.P. Sikora, C.R. Strohman
CLASSE, Ithaca, New York, USA
S. Calatroni, G. Rumolo
CERN, Geneva, Switzerland
K. Kanazawa, Y. Suetsugu
KEK, Ibaraki, Japan
M.T.F. Pivi, L. Wang
SLAC, Menlo Park, California, USA

Funding: Work supported by the US National Science Foundation (PHY-0734867) and Department of Energy (DE-FC02-08ER41538)
Over the course of the past three years, the Cornell Electron Storage Ring (CESR) has been reconfigured to serve as a test facility for next generation particle accelerators. A significant part of this program has been the installation of several diagnostic devices to measure and quantify the electron cloud effect, a potential limiting factor in these machines. In particular, more than 30 Retarding Field Analyzers (RFAs) have been installed in CESR. These devices measure the local electron cloud density and energy distribution, and can be used to evaluate the efficacy of different cloud mitigation techniques. This paper will provide an overview of RFA results obtained at CesrTA over the past year, including measurements taken as function of bunch spacing and wiggler magnetic field. Understanding these results provides a great deal of insight into the behavior of the electron cloud.