Veitzer, S.

Paper	Title	Page
PST06	Effects of Reflections on TE-Wave Measurements of Electron Cloud Density	103
	K. Sonnad, J. Sikora Cornell University - CLASSE K. Hammond Harvard University S. Veitzer Tech-X Corporation
	The simulation code VORPAL has been used as a tool to study charecteristics of TE wave transmission in the presence of electron clouds for CesrTA. We look at how the electron cloud induced phase shift is influenced by (1) reflections of the wave, caused by possible protrusions in the beam pipe and (2)effect of nonuniformities of the cloud density distribution in the transverse plane.
MOD03	Accurate Simulation of the Electron Cloud in the Fermilab Main Injector with VORPAL	152
	P. Lebrun, P. Spentzouris Fermilab J. Cary University of Colorado Boulder S. Veitzer, P. Stoltz Tech-X Corporation
	We present results from a precision simulation of the electron cloud (EC) problem in the Fermilab Main Injector using the code VORPAL. Fully 3D and self consistent that include both distributions of electrons in 6D phase-space and E. M. field maps. Various configurations of the magnetic fields found around the machine have been studied. Plasma waves associated to the fluctuation density of the cloud have been analyzed. Our results are compaired with those obtained with the POSINST code. It is shown that the 3D effects are important. The response of a Retarding Field Analyzer (RFA) to the EC has been simulated, as well as the more challenging microwave absorption experiment. Definite predictions of their exact response are difficult to compute, mostly because of the uncertainties in the secondary emission yield and, in the case of the RFA, because of the sensitivity of the electron collection efficiency to unknown stray magnetic fields. Nonetheless, our simulations do provide guidance to the experimental program.
	Slides
MOD04	Modeling Electron Cloud Buildup and Microwave Diagnostics using VORPAL	162
	S. Veitzer, P. Stoltz Tech-X Corporation K. Sonnad Cornell University - CLASSE P. Lebrun Fermilab
	We present an overview of recent electron cloud modeling results using the multi-dimensional, parallel, plasma simulation code VORPAL. We have used VORPAL to model cloud buildup in dipole, quadrupole, and field-free magnetic field configurations, in both circular and elliptical cross section pipes relevant to microwave diagnostics at the PEP-II experiment at SLAC, and ongoing experiments in the Main Injector at Fermilab. In addition, we present preliminary results for modeling electron orbits in the CesrTA wiggler, which is the beginning of a more detailed modeling effort to understand electron cloud effects in electron/positron accelerators, as well as connecting microwave side-band measurements to cloud densities. We also report on recent 3-Dimensional microwave transmission simulations through uniform and non-uniform clouds, and with higher order TE and TM waves using VORPAL.
	Slides