modifying the rest of the optics (Figure
➊
).
This new optics setting redistributes the
large off-momentum particle orbits; the
amplitudes are now much reduced at the
SDC15 location, while they are increased
at the horizontal scraper location which is
dedicated to collect the beam losses. The
last step keeps the previous advantages
(gain in the performance and the reduced
betatron coupling dependency) along with
suppressing losses in the SDC15 straight
section.
Since October 2013, this new optics has
been in operation. The previous excess
of activation in the SDC15 region has
effectively been suppressed; the sensitivity
to a possible skew corrector failure has
been discarded; today for whatever
ID configuration, during operation, the
injection efficiency and beam lifetime are
routinely kept around 80% with a 13 h
electron beam lifetime (for 430 mA stored
current in hybrid filling pattern), exhibiting
a 20% increase, for both parameters, as
compare to the 2012 optics.
Accelerator Physics Group
ASSOCIATED PUBLICATION
Alexandre Loulergue*
* Synchrotron SOLEIL, l’Orme des Merisiers,
St Aubin BP48, 91192 Gif sur Yvette Cedex,
France
CORRESPONDING AUTHOR
➋
Frequency map analysis of the 2012 optics, on-momentum left and off-momentum right.
(The working point is 18.176/10.234, chromaticities are 1.4/2.4).
➌
Frequency map analysis of the new optics, on-momentum left and off-momentum right
(The working point is 18.155/10.229, chromaticities are 1.2/2.0).
REFERENCE
[1] A. Loulergue, SOLEIL Highlights 122 (2011)
137
SOLEIL
HIGHLIGHTS
2013
