Author: Balewski, K.
Paper Title Page
MOPS055 Observation of Intensity Dependent Single Bunch Effects at the Synchrotron Light Source PETRA III 730
 
  • R. Wanzenberg, K. Balewski
    DESY, Hamburg, Germany
 
  At DESY the PETRA ring is operated as a synchrotron radiation facility with a very low emittance of 1 nm. Regular user operation has started in summer 2010. A summary of observations and measurements of intensity dependent single bunch effects is presented in this report. The longitudinal impedance of the ring is estimated from the measured bunch length versus beam intensity. The results are compared with predictions from the impedance model. Furthermore measurements of the single bunch intensity limit due to the transverse mode coupling instability (TMCI) are reported. The tune and phase shift around the ring has been measured as a function of the beam intensity. At PETRA III tune spectra have been observed with some characteristics which have been observed at other storage rings in connection with electron cloud effects. The present status of the observations of potential electron cloud effects is also discussed.  
 
THPC020 PETRA III Upgrade 2948
 
  • K. Balewski, M. Bieler, J. Keil, A. Kling, G.K. Sahoo, R. Wanzenberg
    DESY, Hamburg, Germany
 
  PETRA III, the new third generation light source at DESY, has been running as a user facility since middle of 2010. All 14 undulator beam lines have been commissioned and up to 12 of them are currently in operation. However, already during the planning phase of PETRA III it turned out that the number of beamlines will not be sufficient to fulfill the request for beam time. The pressure to add more beamlines to PETRA III even increased after the decision to shut down DORIS III at the end of 2012. To increase the number of experimental stations two additional halls will be built each housing 5 additional beam lines and about 100 m of the accelerator close to each of the new buildings will be completely remodeled to install additional undulators. The upgrade has been formally approved and at present should be accomplished during a 6 month shut down in 2013. In this paper the layout of the upgraded accelerator will be shown. The impact of the upgrade on machine performance has been studied both theoretically and experimentally and the results of these studies will be presented.  
 
THPC156 Performance of the PETRA III APPLE II Undulator 3254
 
  • J. Bahrdt, W. Frentrup, A. Gaupp, M. Scheer
    HZB, Berlin, Germany
  • K. Balewski, J. Keil, A. Schöps, M. Tischer
    DESY, Hamburg, Germany
 
  A 5m-long APPLE II undulator has been built in collaboration between Helmholtz-Zentrum Berlin and DESY Hamburg. Magnetic field measurements after the final shimming in the laboratory are presented. The device has been installed in the storage ring and machine studies have been performed. The tune shifts in the elliptical and the inclined mode are in agreement with predictions from theory. The dynamic field integrals have successfully been minimized in the storage ring with so-called L-shims (rectangular iron sheets) which are placed at the undulator center at the magnet edges.