IPAC2013 - List of Authors (Popovic, M.)

Paper	Title	Page
TUPFI068	High Power Tests of Alumina in High Pressure RF Cavities for Muon Ionization Cooling Channel	1508
	L.M. Nash University of Chicago, Chicago, Illinois, USA G. Flanagan, R.P. Johnson, F. Marhauser, J.H. Nipper Muons. Inc., USA M.A. Leonova, A. Moretti, M. Popovic, A.V. Tollestrup, K. Yonehara Fermilab, Batavia, USA Y. Torun IIT, Chicago, Illinois, USA
	It is important to make a compact muon ionization cooling channel to increase the cooling efficiency (muon survival rate, cooling decrement, etc). A proposed scheme to reduce the radial size of RF cavities at a given resonance frequency is to insert a dielectric material into the RF cavity. In vacuum cavities, however, dielectric materials are extremely susceptible to breakdown in high power conditions. High-pressure hydrogen gas has been shown to inhibit breakdown events in RF cavities in strong magnetic fields. An experiment has been designed to test surface breakdown of alumina in RF cavities. A structure has been designed to maximize the parallel field parallel to the surface while bringing the cavity into a desired frequency range (800-810MHz). Alumina is tested in this configuration under high power conditions. The experimental result will be shown in this presentation.

Paper

Title

Page

High Power Tests of Alumina in High Pressure RF Cavities for Muon Ionization Cooling Channel

1508

L.M. Nash
University of Chicago, Chicago, Illinois, USA
G. Flanagan, R.P. Johnson, F. Marhauser, J.H. Nipper
Muons. Inc., USA
M.A. Leonova, A. Moretti, M. Popovic, A.V. Tollestrup, K. Yonehara
Fermilab, Batavia, USA
Y. Torun
IIT, Chicago, Illinois, USA

It is important to make a compact muon ionization cooling channel to increase the cooling efficiency (muon survival rate, cooling decrement, etc). A proposed scheme to reduce the radial size of RF cavities at a given resonance frequency is to insert a dielectric material into the RF cavity. In vacuum cavities, however, dielectric materials are extremely susceptible to breakdown in high power conditions. High-pressure hydrogen gas has been shown to inhibit breakdown events in RF cavities in strong magnetic fields. An experiment has been designed to test surface breakdown of alumina in RF cavities. A structure has been designed to maximize the parallel field parallel to the surface while bringing the cavity into a desired frequency range (800-810MHz). Alumina is tested in this configuration under high power conditions. The experimental result will be shown in this presentation.