Paper |
Title |
Page |
PM08 |
Recent Advances in the Measurement of Chromaticity Via Head-Tail Phase Shift Analysis
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107 |
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- N. Catalan-Lasheras, S. Fartoukh, R. Jones
CERN, Geneva, Switzerland
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A so-called "Head-Tail" monitor has been operational in the CERN-SPS for
a few years. The measurement of chromaticity using such a monitor relies
on the periodic dephasing and rephasing that occurs between the head and
tail of a single bunch for non-zero chromaticity. By measuring the
turn-by-turn position data from two longitudinal positions in a bunch it
is possible to extract the relative dephasing of the head and the tail,
and so to determine the chromaticity. Until recently this technique had
suffered from an unexplained missing factor when compared to
conventional chromaticity measurements. This paper explains the source of
this factor and also reports on the considerable experimental, simulation
and analysis effort that has qualified the technique for use in the LHC.
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