Conventional Magnets/Hadron Colliders

Paper Title Page
MPPT006 The Extraction Kicker System of the RCS in J-PARC 1009
  • J. Kamiya, T. Takayanagi
    JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  • T. Kawakubo, S. Murasugi, E. Nakamura
    KEK, Ibaraki
  The kicker magnet plays a role of extracting the proton beam which is accelerated up to 3GeV by the Rapid Cycling Synchrotron in J-PARC. The kicker system is required the fast rise time of the magnetic field because the interval between the beam bunches is only 349nsec. The kicker magnet is the distributed type. The findings in our measurements revealed that the delay time in the magnet is about 180nsec. The power supply has the pulse forming network system, which consists of co-axial cables whose characteristic impedance is 10 ohm. We accomplished the current rise time of 80 nsec quickness. Therefore we had a good prospect of the fast rise time of the magnetic field. The characteristic impedance of the kicker magnet was also measured. The value was close to 10 ohm. There will be no large mismatching between the power supply and the magnet. This pulse magnet is installed in the vacuum chamber to prevent the electric discharge. Outgas from the components has the adverse effects the vacuum in the accelerator. We have reduced the outgas rate from the ferrite core and aluminum plates which construct the magnet by backing them at appropriate temperature.  
MPPT007 Design of the Pulse Bending Magnets for the Injection System of the 3-GeV RCS in J-PARC 1048
  • T. Takayanagi, Y. Irie, J. Kamiya
    JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  • T. Kawakubo, I. Sakai
    KEK, Ibaraki
  The pulse bending magnets for the injection system of the 3-GeV RCS in J-PARC has been designed using a 3D magnetic analysis code. The injection system consists of the pulse bending magnets for the injection bump orbit, which are four horizontal bending magnets (shift bump), four horizontal painting magnets (h-paint bump), and two vertical painting magnets (v-paint bump). The injection beam energy and the extraction beam power are 400 MeV and 1 MW at 25-Hz repetition rate, respectively. The beam orbit area with a full acceptance beam of the injection beam, painting beam and the circulating beam at the shift bump points is a 400 mm width and a 250 mm height.The shift bump has accomplished 1.0% good field region at 0.22 T.  
MPPT009 HTS Power Leads for the BTeV Interaction Region 1147
  • SF. Feher, R. H. Carcagno, D.F. Orris, Y.M.P. Pischalnikov, R. Rabehl, C. Sylvester, M. Tartaglia, J. Tompkins
    Fermilab, Batavia, Illinois
  Funding: DOE

A new Interaction Region for the BTEV experiment is planned to be built soon at Fermilab. This IR will require new superconducting quadrupole magnets and many additional power circuits for their operation. The new "low beta" quadupole magnet design is based upon the Fermilab LHC quadrupole design, and will operate at 9.56 kA in 4.5 K liquid helium. The use of conventional power leads for these circuits would require substantially more helium for cooling than is available from the cryogenic plant, which is already operating close to its limit. To decrease the heat load and helium cooling demands, the use of HTS power leads is necessary. Fermilab is in the process of procuring HTS leads for this new interaction region. Several 6 kA HTS leads produced by American Superconductor Corporation have been tested at over-current conditions. Based on the test results, design requirements are being developed for procuring the HTS current leads. This paper summarizes the test results and describes the design requirements for the 9.65 kA HTS power leads.

MPPT010 A New Correction Magnet Package for the Fermilab Booster Synchrotron 1204
  • V.S. Kashikhin, D.J. Harding, J.A. John, J.R. Lackey, A. Makarov, W. Pellico, E. Prebys
    Fermilab, Batavia, Illinois
  Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-76CH03000.

Since its initial operation over 30 years ago, most correction magnets in the Fermilab Booster Synchrotron have only been able to fully correct the orbit, tunes, coupling, and chromaticity at injection (400MeV). We have designed a new correction package, including horizontal and vertical dipoles, normal and skew quadrupoles, and normal and skew sextupoles, to provide control up to the extraction energy (8GeV). In addition to tracking the 15Hz cycle of the main, combined function magnets, the quadrupoles and sextupoles must swing through their full range in 1ms during transition crossing. The magnet is made from 12 water-cooled racetrack coils and an iron core with 12 poles, dramatically reducing the effective magnet air gap and increasing the corrector efficiency. Magnetic field analyses of different combinations of multipoles are included.

MPPT013 New Pulsed Orbit Bump Magnets for the Fermilab Booster Synchrotron 1341
  • J.R. Lackey, D.J. Harding, J.A. John, V.S. Kashikhin, A. Makarov, E. Prebys
    Fermilab, Batavia, Illinois
  Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-76CH03000.

The beam from the Fermilab Linac is injected onto a bump in the closed orbit of the Booster Synchrotron where a carbon foil strips the electrons from the Linac’s negative ion hydrogen beam. Although the Booster itself runs at 15Hz, heat dissipation in the orbit bump magnets has been one limitation to the fraction of the cycles that can be used for beam. New, 0.28T pulsed window frame dipole magnets have been constructed that will fit into the same space as the old ones, run at the full repetition rate of the Booster, and provide a larger bump to allow a cleaner injection orbit. The new magnets use a high saturation flux density Ni-Zn ferrite in the yoke rather than laminated steel. The presented magnetic design includes two and three dimensional magnetic field calculations with eddy currents and ferrite nonlinear effects.