| DATE: |
2003-11-06 13:30 - 15:30 |
| PLACE: |
Building 2, No.203 |
| TITLE: |
Accelerator Physics Seminar [Electron cloud in the GSI-SIS18 and role of elastically reflected electrons] |
| SPEAKER: |
Giovanni Rumolo (GSI) |
| LANGUAGE: |
English |
| ABSTRACT: |
According to the GSI future project, the existing synchrotron SIS18 will
be upgraded to be used as an injector for the planned larger synchrotron
SIS100. All possible operation scenarios require the acceleration in the
SIS18 of 4x10^(10) U^(73+) (either packed in 4 80ns long bunches with a
100ns spacing, or in one single uniform long -500 ns- bunch) up to 1
GeV/u.
An electron cloud can therefore form in the machine, as the intensities
will be pushed to these unprecedented high values.
We study numerically the SEY threshold for the onset of the electron cloud
build up and the possible resulting bunch instabilities.
We stress the importance of low energy reflected electrons in the process,
referring to recent measurements which have led to a new SEY
parametrization in which the probability of reflection becomes 1 for
vanishing energy of the incident electron.
The importance of rediffused electrons in simulations is also finally
shortly addressed as subject presently under study.
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