Speaker
Description
Standard quadrupole beam-based alignment (BBA) techniques rely on
orbit data and on the sequential variation of quadrupole and
corrector magnets (CM). This results in time consuming measurements
of the order of several hours. Fast (10
kHz) beam position monitors (BPM) and CMs with ac power supplies are
routinely used in modern synchrotron light sources to drive fast
orbit feedback systems. In this paper we show how they can be
employed to reduce the time for the BBA
to several minutes only, ensuring the same level of accuracy and
precision. Moreover, conversely to the standard BBA, the new
procedure accounts automatically for any level of betatron coupling,
BPM roll and OCM tilt. In the case of the ALBA 3rd generation light
source, the time for a complete measurement dropped from 5 hours to
10 minutes, a reduction by a factor 30. As further extension of this
novel approach, an even faster skew quadrupole BBA was demonstrated
in ALBA for the first time, taking advantage of the additional ac
modulation of the skew quadrupole field. Results from this fully ac
measurement are compared with those obtained via dc
scan of the skew quadrupole.
