Author: Marsh, W.L.
Paper Title Page
WEPPR085 Observation of Instabilities of Coherent Transverse Ocillations in the Fermilab Booster 3129
  • Y. Alexahin, N. Eddy, E. Gianfelice-Wendt, V.A. Lebedev, W.L. Marsh, W. Pellico, A.K. Triplett
    Fermilab, Batavia, USA
  Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
The Fermilab Booster - built more than 40 years ago - operates well above the design proton beam intensity of 4.e12 ppp. Still, the Fermilab neutrino experiments call for even higher intensity of 5.5·1012 ppp. A multitude of intensity related effects must be overcome in order to meet this goal including suppression of coherent dipole instabilities of transverse oscillations which manifest themselves as a sudden drop in the beam current. In this report we present the results of observation of these instabilities at different tune, coupling and chromaticity settings and discuss possible cures.
THPPP019 Tune Determination of Strongly Coupled Betatron Oscillations in a Fast Ramping Synchrotron 3770
  • Y. Alexahin, E. Gianfelice-Wendt, W.L. Marsh, A.K. Triplett
    Fermilab, Batavia, USA
  Funding: Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Tune identification - i.e. attribution of the spectral peak to a particular normal mode of oscillations - can present a significant difficulty in the presence of strong transverse coupling when the normal mode with a lower damping rate dominates spectra of Turn-by-Turn oscillations in both planes. The introduced earlier phased sum algorithm* helped to recover the weaker normal mode signal from the noise, but by itself proved to be insufficient for automatic peak identification in the case of close phase advance distribution in both planes. To resolve this difficulty we modified the algorithm by taking and analyzing Turn-by-Turn data for two different ramps with the beam oscillation excited in each plane in turn. Comparison of the relative amplitudes of Fourier components allows for automatic correct tune identification. The proposed algorithm was implemented in the Fermilab Booster B38 console application and successfully used in tune, coupling and chromaticity measurements.
* Y. Alexahin, E. Gianfelice-Wendt, W. Marsh, Proc. IPAC10, Kyoto, May 2010, p. 1179.
THPPP024 Alignment and Aperture Scan at the Fermilab Booster 3785
  • K. Seiya, J.R. Lackey, W.L. Marsh, W. Pellico, D.A. Still, A.K. Triplett, A.M. Waller
    Fermilab, Batavia, USA
  The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2·1017 protons/hour, which is almost double the current operation at 1.1017 protons/hour. The beam loss in the machine is going to be the source of issues. The booster accelerates beam from 400 MeV to 8 GeV and extracts to the Main Injector. Several percent of the beam is lost within 3 msec after the injection. The aperture at injection energy was measured and compared with the survey data. The magnets are going to be realigned in March 2012 in order to increase the aperture. The beam studies, analysis of the scan and alignment data, and the result of the magnet moves will be discussed in this paper.