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Pivi, Mauro T.F.

Publications and source records attributed to Pivi, Mauro T.F..

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Update of the Electron Cloud Simulations for DAFNE

A strong horizontal instability, limiting the positron current at I {approx} 500mA, has been observed at DAFNE since the installation of the FINUDA detector in 2003. Experiments and simulations seem to provide evidence that the electron cloud build-up in the wigglers and bending magnets of the DAFNE positron ring induces coupled bunch instability with features compatible with observations. Recently the installation of a new horizontal feedback system allowed to control the instability for value of the positron current as high as possible (I {approx} 1000mA). To better understand the electron cloud effects and possibly to find a remedy, a detailed simulation study is undergoing. In this communication we present recent simulation results relative to the single bunch instability induced by an electron cloud interacting with the beam.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2011

Experiments on Electron Cloud Mitigation at PEP-II

The electron cloud effect has been observed at many accelerator facilities. It has been the subject of many workshops and reviews. An electron cloud is formed when low energy photoelectrons released from the vacuum chamber surfaces and ionized residual gas molecules, driven by the beam fields of passing positively charged bunches, impinge on the chamber walls and create secondary emission. It is an important issue for many currently operating facilities and the damping rings of the proposed International Linear Collider (ILC) because beam-cloud interaction can severely impact the machines performance. Systematic studies on the electron cloud effect, and its possible remedies, have been carried out in many laboratories. At SLAC, the effort has been concentrated on theoretical understanding with the aid of computer simulations, and experimental measurements with high intensity positron beams at PEP-II. Computer simulation results have been presented at ECLOUD07 and in an earlier article in this journal. In this article, we present recent results from electron cloud experiments at the positron storage ring of PEP-II. In particular, we discuss the performance of various mitigation techniques.

43 PARTICLE ACCELERATORS↗