PCaPAC2012 - List of Keywords (emittance)

Paper	Title	Other Keywords	Page
WEPD22	Post-Mortem Analysis of BPM-Interlock Triggered Beam Dumps at PETRA-III	GUI, controls, ion, synchrotron	43
	G.K. Sahoo, K. Balewski, A. Kling DESY, Hamburg, Germany
	PETRA-III is a 3rd generation synchrotron light source dedicated to users at 14 beam lines with 30 instruments. This operates with several filling modes such as 60, 240 and 320 bunches with 100mA or 40 bunches with 80mA at a positron beam energy of 6 GeV. The horizontal beam emittance is 1nmrad while a coupling of 1% amounts to a vertical emittance of 10pmrad. During a user run unscheduled beam dumps triggered by Machine Protection System may occur. In many cases the reason can be identified but in some it remains undetected. Though the beam is lost some signature is left in the ring buffers of the 226 BPM electronics where last 16384 turns just before the dump are available for post-mortem analysis. Scrutinizing turn by turn orbits and the frequency spectrum measured at a BPM can improve understanding of such a beam loss and may help to increase the efficiency of operation by eliminating the sources. Here we discuss in detail the functionality of a Java GUI used to investigate the reasons for unwanted dumps. In particular, the most effective corrector method is applied to identify correctors that might have perturbed the golden orbit leading to violations of the interlock limits.

Paper

Title

Other Keywords

Page

WEPD22

Post-Mortem Analysis of BPM-Interlock Triggered Beam Dumps at PETRA-III

GUI, controls, ion, synchrotron

43

G.K. Sahoo, K. Balewski, A. Kling
DESY, Hamburg, Germany

PETRA-III is a 3rd generation synchrotron light source dedicated to users at 14 beam lines with 30 instruments. This operates with several filling modes such as 60, 240 and 320 bunches with 100mA or 40 bunches with 80mA at a positron beam energy of 6 GeV. The horizontal beam emittance is 1nmrad while a coupling of 1% amounts to a vertical emittance of 10pmrad. During a user run unscheduled beam dumps triggered by Machine Protection System may occur. In many cases the reason can be identified but in some it remains undetected. Though the beam is lost some signature is left in the ring buffers of the 226 BPM electronics where last 16384 turns just before the dump are available for post-mortem analysis. Scrutinizing turn by turn orbits and the frequency spectrum measured at a BPM can improve understanding of such a beam loss and may help to increase the efficiency of operation by eliminating the sources. Here we discuss in detail the functionality of a Java GUI used to investigate the reasons for unwanted dumps. In particular, the most effective corrector method is applied to identify correctors that might have perturbed the golden orbit leading to violations of the interlock limits.