DIPAC2011 - List of Authors (Tiessen, H.)

Paper	Title	Page
MOPD76	The Petra III Fast Orbit Feedback System	221
	J. Klute, K. Balewski, H.T. Duhme, H. Tiessen, F. Wierzcholek DESY, Hamburg, Germany
	Orbit stability is a crucial and import issue of 3rd generation light sources. Ambient mechanical and electrical noise cause rather large orbit distortions which have to be counteracted by an orbit feedback. Extensive studies of the orbit distortions in PETRA III have shown that the frequencies of the ambient noise lie within a frequency range from about 0.01Hz to 100Hz. In this paper we describe the main components, their properties and the layout of PETRA III’s orbit feedback. Furthermore experimental results on short and long term stability will be presented. It will be shown that the required orbit stability of ±0.5 μm in the vertical plane can be maintained over 50 h.

TUPD43	XFEL Beam Loss Monitor System	401
	A. Kaukher, I. Krouptchenkov, B. Michalek, D. Nölle, H. Tiessen DESY, Hamburg, Germany
	European XFEL will have a sophisticated Machine Protection System, part of which - Beam Loss Monitors(BLM). The monitors will detect losses of electron beam, in order to protect the components of the XFEL from damage and excessive activation. For protection of undulators, BLMs with a scintillator bar will be used. BLMs at places with high radiation load will be equipped with fused silica rods. Beam dumps of the XFEL will be instrumented with glass-fiber BLMs. The BLMs were tested with an electron test-beam at DESY, as well as at FLASH. Due to large amount of light produced by scintillator and high gain of the used photomultiplier, no optical grease is needed in front of the photomultiplier' window, while typical cathode voltage is only 500-600 volt. The prototype with quartz glass was typically operated at higher cathode voltage. Good operation of all three types of BLMs prototypes was obtained. It is planned to use same monitors also for the FLASH2 project. Current status of the XFEL BLM system development will be presented.

Paper

Title

Page

The Petra III Fast Orbit Feedback System

221

J. Klute, K. Balewski, H.T. Duhme, H. Tiessen, F. Wierzcholek
DESY, Hamburg, Germany

Orbit stability is a crucial and import issue of 3rd generation light sources. Ambient mechanical and electrical noise cause rather large orbit distortions which have to be counteracted by an orbit feedback. Extensive studies of the orbit distortions in PETRA III have shown that the frequencies of the ambient noise lie within a frequency range from about 0.01Hz to 100Hz. In this paper we describe the main components, their properties and the layout of PETRA III’s orbit feedback. Furthermore experimental results on short and long term stability will be presented. It will be shown that the required orbit stability of ±0.5 μm in the vertical plane can be maintained over 50 h.

TUPD43

XFEL Beam Loss Monitor System

401

A. Kaukher, I. Krouptchenkov, B. Michalek, D. Nölle, H. Tiessen
DESY, Hamburg, Germany

European XFEL will have a sophisticated Machine Protection System, part of which - Beam Loss Monitors(BLM). The monitors will detect losses of electron beam, in order to protect the components of the XFEL from damage and excessive activation. For protection of undulators, BLMs with a scintillator bar will be used. BLMs at places with high radiation load will be equipped with fused silica rods. Beam dumps of the XFEL will be instrumented with glass-fiber BLMs. The BLMs were tested with an electron test-beam at DESY, as well as at FLASH. Due to large amount of light produced by scintillator and high gain of the used photomultiplier, no optical grease is needed in front of the photomultiplier' window, while typical cathode voltage is only 500-600 volt. The prototype with quartz glass was typically operated at higher cathode voltage. Good operation of all three types of BLMs prototypes was obtained. It is planned to use same monitors also for the FLASH2 project. Current status of the XFEL BLM system development will be presented.