Dr
Robert Macek
(LANL and TechSource, Inc.)
10/9/10, 9:30 AM
Oral Sessions
Recent beam studies have focused on two aspects of the observed e-p instability at the Los Alamos Proton Storage Ring (PSR). 1) Most recently it has been observed that a stable beam with the standard production bunch width (290 ns injected beam bunch width) will become e-p unstable when the bunch width is shortened to 200 ns or less. This was not the case years earlier. Experimental...
Dr
Robert Zwaska
(Fermilab)
10/9/10, 10:00 AM
Oral Sessions
Using the new measurement station in the Main Injector, we have made a series of ECloud measurements in 2009 and 2010. The installation included Titanium-Nitride (TiN) and amorphous carbon coated beam pipes; these materials were directly compared to an adjacent stainless chamber through measurement with Retarding Field Analyzers (RFAs). Over the long period of running we were able to observe...
Christina Yin Vallgren
(CERN)
10/9/10, 11:00 AM
Oral Sessions
Amorphous carbon (a-C) thin films, produced in different coating configurations by using d.c magnetron sputtering, have been investigated in laboratory for low secondary electron yield (SEY) applications. After the coatings had shown a reliable low initial SEY, the a-C thin films have been applied in the SPS and tested with LHC type beams. Currently, we have used a-C thin film coated in...
Dr
Sara Casalbuoni
(Karlsruhe Institute of Technology)
10/9/10, 11:30 AM
Oral Sessions
Preliminary studies performed with the cold bore superconducting undulator installed in the ANKA (Angstrom source Karlsruhe) storage ring suggest that the beam heat load is mainly due to the electron wall bombardment. Electron bombardment can both heat the cold vacuum chamber and induce an increase in the pressure because of gas desorption. In this contribution we compare the measurements of...
Theo Demma
(INFN LNF)
10/9/10, 12:00 PM
Oral Sessions
A strong horizontal instability limiting the positron current has been observed at DAFNE since the installation of the FINUDA detector in 2003. Experiments and simulations seem to provide an evidence that the electron cloud build-up in the wigglers and bending magnets of the DAFNE positron ring induces a coupled bunch instability with features compatible with observations . To better...
