DESY, Hamburg
PETRA III is a new hard x-ray synchrotron radiation source which will be operated at 6 GeV with an extremely low horizontal emittance of 1 nmrad. This new facility is the result of a conversion of the existing storage ring PETRA II into a light source. The conversion comprises the complete rebuilding of one eighth of the 2304 m long storage ring, which will then house 14 undulator beam lines, the optical and experimental hutches, and the modernization and refurbishment of the remaining seven eighths. In addition two 100 m long damping wiggler sections have been installed which are required to achieve the small design emittance. Construction, installation and technical commissioning have been finished middle of March and then the commissioning with beam started. In this paper we present the results that have been achieved during commissioning with special emphasis on the role of diagnostic systems.
DESY, Hamburg
The new synchrotron light source PETRA III is powered by a chain of pre-accelerators including Linac II, PIA, transfer lines, and DESY II. The whole chain is equipped with upgraded versions of diagnostic systems that were installed during the 2008 shutdown. This paper presents the upgrade of the beam position monitor (BPM) systems at PIA together with the transfer lines and DESY II. All systems rely on the ‘Delay Multiplex Single Path Technology’ (DMSPT). It is demonstrated that the self-triggered design of the BPM electronics is specifically suited to the different needs of such a heterogeneous pre-accelerator chain. Structures and dependencies of the BPM systems will be described in detail.
INFN/LNF, Frascati (Roma)
Università di Roma II Tor Vergata, Roma
DESY, Hamburg
The characterization of the transverse phase space for high charge density and high energy electron beams is demanding for the successful development of the next generation light sources and linear colliders. Due to its non-invasive and non-intercepting features, Optical Diffraction Radiation (ODR) is considered as one of the most promising candidates to measure the transverse beam size and angular divergence. A thin stainless steel mask has been installed at 45° with respect to the DR target and normally to the beam propagation to reduce the contribution of synchrotron radiation background. In addition, interference between the ODR emitted on the shielding mask in the forward direction and the radiation from the DR target in the backward direction is observed. This is what we call Optical Diffraction Interferometry (ODRI). The contribution of this interference effect to the ODR angular distribution pattern and, consequently, its impact on the beam transverse parameters is discussed. Results of an experiment, based on the detection of the ODRI angular distribution to measure the electron beam transverse parameters and set up at FLASH (DESY, Hamburg) are discussed in this paper.
DESY, Hamburg
PETRA III, a new high-brilliance synchrotron radiation source, is under commissioning at DESY. Its beam position measurement system is based on the Libera Brilliance electronics. BPM system is used for machine starting up and development. The system will also be used for the beam observation and orbit feedback. This paper presents the infrastructure, features of the BPM system and experience with the commissioning of the BPM electronics.
DESY, Hamburg
IKP, Mainz
For the European XFEL with a maximum beam energy of 20 GeV and an average beam power of up to 300 kW it is planned to install beam profile monitors in the dump sections in order to control beam position and size. Usually OTR monitors are used for electron profile measurements. For intense beams however, thermal load in the screen material may result in resolution degradation and even screen damage. To overcome this problem the beam can be swept over the screen, but the strong OTR light emission directivity will reduce the optical system's collection efficiency. Therefore it is planned to use luminescent screens because of their robustness and isotropic light emission. While only little information is available about scintillator properties for applications with high energetic electrons, a test experiment has been performed at the 855 MeV beam of the Mainz Microtron MAMI in order to study light yield and robustness of different screen materials like Aluminum and Zirconium oxide under electron bombardment. The results will be compared to independent measurements from studies with heavy ion beams.