DIPAC2011 - List of Keywords (linear-collider)

Paper	Title	Other Keywords	Page
MOPD80	An FPGA-based Bunch-by-Bunch Position and Angle Feedback System at ATF2	feedback, kicker, extraction, collider	233
	G.B. Christian, R. Apsimon, D.R. Bett, B. Constance, M.R. Davis JAI, Oxford, United Kingdom P. Burrows, C. Perry Oxford University, Physics Department, Oxford, Oxon, United Kingdom A. Gerbershagen CERN, Geneva, Switzerland J. Resta-López IFIC, Valencia, Spain
	The FONT5 intra-train feedback system serves as a prototype for an interaction point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider. The system has been tested on the KEK Accelerator Test Facility (ATF) and is deployed to stabilise the beam orbit at the ATF2. The goal of this system is to correct both position and angle jitter in the vertical plane, providing stability of ~1 micron at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kicker-drive amplifiers. An overview of the hardware, and the latest results from beam tests at ATF2, will be presented. The total latency of the system with coupled position and angle feedback loops operating simultaneously was measured to be approximately 140 ns. The greatest degree of correction observed was down to a jitter of 0.4 microns at one of the feedback BPMs, a factor of six compared to the uncorrected beam jitter, for a very high degree of bunch-to-bunch correlation.

TUPD93	Diagnostics of RF Breakdowns in High-Gradient Accelerating Structures	collider, plasma, electron, vacuum	527
	A. Palaia Uppsala University, Uppsala, Sweden V.A. Dolgashev, J.R. Lewandowski, S.P. Weathersby SLAC, Menlo Park, California, USA
	Within the framework of the research on high-gradient accelerating structures for future linear colliders, diagnostics of radio-frequency (RF) breakdowns is of great importance to support the understanding of the vacuum breakdown process. Measurements of RF and electron and ion currents emitted during and after a breakdown can be used to calculate the properties of any objects responsible for such power reflection and charge emission. Possible breakdown models, breakdown localization and a time-scale of the process are here discussed and compared to dedicated measurements. First results are presented.
	Poster TUPD93 [7.029 MB]

Paper

Title

Other Keywords

Page

MOPD80

An FPGA-based Bunch-by-Bunch Position and Angle Feedback System at ATF2

feedback, kicker, extraction, collider

233

G.B. Christian, R. Apsimon, D.R. Bett, B. Constance, M.R. Davis
JAI, Oxford, United Kingdom
P. Burrows, C. Perry
Oxford University, Physics Department, Oxford, Oxon, United Kingdom
A. Gerbershagen
CERN, Geneva, Switzerland
J. Resta-López
IFIC, Valencia, Spain

The FONT5 intra-train feedback system serves as a prototype for an interaction point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider. The system has been tested on the KEK Accelerator Test Facility (ATF) and is deployed to stabilise the beam orbit at the ATF2. The goal of this system is to correct both position and angle jitter in the vertical plane, providing stability of ~1 micron at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kicker-drive amplifiers. An overview of the hardware, and the latest results from beam tests at ATF2, will be presented. The total latency of the system with coupled position and angle feedback loops operating simultaneously was measured to be approximately 140 ns. The greatest degree of correction observed was down to a jitter of 0.4 microns at one of the feedback BPMs, a factor of six compared to the uncorrected beam jitter, for a very high degree of bunch-to-bunch correlation.

TUPD93

Diagnostics of RF Breakdowns in High-Gradient Accelerating Structures

collider, plasma, electron, vacuum

527

A. Palaia
Uppsala University, Uppsala, Sweden
V.A. Dolgashev, J.R. Lewandowski, S.P. Weathersby
SLAC, Menlo Park, California, USA

Within the framework of the research on high-gradient accelerating structures for future linear colliders, diagnostics of radio-frequency (RF) breakdowns is of great importance to support the understanding of the vacuum breakdown process. Measurements of RF and electron and ion currents emitted during and after a breakdown can be used to calculate the properties of any objects responsible for such power reflection and charge emission. Possible breakdown models, breakdown localization and a time-scale of the process are here discussed and compared to dedicated measurements. First results are presented.

Poster TUPD93 [7.029 MB]