IBIC2012 - List of Authors (Peake, D.J.)

Paper	Title	Page
TUPB84	Storage Ring Tune Measurements using High-speed Metal-semiconductor-metal Photodetector	537
	S. Dawson, D.J. Peake, R.P. Rassool The University of Melbourne, Melbourne, Australia M.J. Boland ASCo, Clayton, Victoria, Australia R.J. Steinhagen CERN, Geneva, Switzerland
	Knowledge of the betatron tunes within a storage ring is important to prevent the creation of instabilities and maximise the lifetime of the stored current within the ring. Typical tune measurements excite the beam and measure the resulting motion over time using electromagnetic pickups. The novel measurement technique presented utilises high-speed MSM photodiodes in a balanced detector set-up to measure the vertical and horizontal betatron tunes. Radiation from a bending magnet consists of both visible light and X-rays. The visible light is separated from the X-rays with an optical chicane and focussed onto a pair of length-matched optical fibers each coupled to an MSM photodiode. The specialised biasing circuit for the photodiodes is constructed in a balanced detector configuration to emphasise any motion in the beam. Signal resulting from beam motion is amplified and digitised for analysis. Using this set-up the tunes for the storage ring at the Australian Synchrotron have been measured and verified with comparison to existing tune measurement technologies. The results from the new optical tune measurement system will be presented and discussed.

Paper

Title

Page

Storage Ring Tune Measurements using High-speed Metal-semiconductor-metal Photodetector

537

S. Dawson, D.J. Peake, R.P. Rassool
The University of Melbourne, Melbourne, Australia
M.J. Boland
ASCo, Clayton, Victoria, Australia
R.J. Steinhagen
CERN, Geneva, Switzerland

Knowledge of the betatron tunes within a storage ring is important to prevent the creation of instabilities and maximise the lifetime of the stored current within the ring. Typical tune measurements excite the beam and measure the resulting motion over time using electromagnetic pickups. The novel measurement technique presented utilises high-speed MSM photodiodes in a balanced detector set-up to measure the vertical and horizontal betatron tunes. Radiation from a bending magnet consists of both visible light and X-rays. The visible light is separated from the X-rays with an optical chicane and focussed onto a pair of length-matched optical fibers each coupled to an MSM photodiode. The specialised biasing circuit for the photodiodes is constructed in a balanced detector configuration to emphasise any motion in the beam. Signal resulting from beam motion is amplified and digitised for analysis. Using this set-up the tunes for the storage ring at the Australian Synchrotron have been measured and verified with comparison to existing tune measurement technologies. The results from the new optical tune measurement system will be presented and discussed.