• K. Yonehara, A. Lunin, A. Moretti, M. Popovic, G.V. Romanov
  Fermilab, Batavia
• R.P. Johnson, M.L. Neubauer
  Muons, Inc, Batavia
• L. Thorndahl
  CERN, Geneva

Funding: supported in part by USDOE STTR Grant DE-FG02-08ER86350

The great advantage of the helical ionization cooling channel (HCC) is its compact structure that enables the fast cooling of muon beam 6-dimensional phase space. This compact aspect requires a high average RF gradient, with few places that do not have cavities. Also, the muon beam is diffuse and requires an RF system with large transverse and longitudinal acceptance. A traveling wave system can address these requirements. First, the number of RF power coupling ports can be significantly reduced compared with our previous pillbox concept. Secondly, by adding a nose on the cell iris, the presence of thin metal foils traversed by the muons can possibly be avoided. We show simulations of the cooling performance of a traveling wave RF system in a HCC, including cavity geometries with inter-cell RF power couplers needed for power propagation.

• W.M. Tam
  IUCF, Bloomington, Indiana
• G. Apollinari, S. Chaurize, S. Hays, G.V. Romanov, V.E. Scarpine, C.W. Schmidt, W.M. Tam, R.C. Webber
  Fermilab, Batavia

The proton ion source for the High Intensity Neutrino Source (HINS) Linac front-end at Fermilab has been successfully commissioned. It produces a 50 keV, 3 msec beam pulse with a peak current greater than 20 mA at 2.5 Hz. The beam is transported to the radio-frequency quadrupole (RFQ) by a low energy beam transport (LEBT) that consists of two focusing solenoids, four steering dipole magnets and a beam current transformer. To understand beam transmission through the RFQ, it is important to characterize the 50 keV beam before connecting the LEBT to the RFQ. A wire scanner and a Faraday cup are temporarily installed at the exit of the LEBT to study the beam parameters. Beam profile measurements are made for different LEBT settings and results are compared to those from computer simulations. In lieu of direct emittance measurements, a solenoid variation method based on profile measurements is used to reconstruct the beam emittance.