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TY - CONF AU - Sikora, J.P. AU - De Santis, S. AU - Li, Y. ED - Henderson, Stuart ED - Akers, Evelyn ED - Satogata, Todd ED - Schaa, Volker R.W. TI - Microwave Modeling for Electron Cloud Density Measurements at CesrTA J2 - Proc. of IPAC2015, Richmond, VA, USA, May 3-8, 2015 C1 - Richmond, VA, USA T2 - International Particle Accelerator Conference T3 - 6 LA - english AB - The electron cloud (EC) density in accelerator beam-pipe has been measured using resonant microwaves. The resonances are produced by changes in beam-pipe geometry that generate reflections and standing waves, with typical behavior being similar to a section of waveguide with shorted ends. The technique uses fact that the EC density will shift the resonant frequencies. In previous analysis, we have made the simplifying approximation that the standing waves are multiples of a half-wavelength and that the magnitude of the electric field is symmetric about the longitudinal center of the resonance. In this paper we show that some changes in beam-pipe geometry will result in asymmetric electric field magnitudes along the resonant length. When this is combined with an EC density that varies along this length, the magnitude of the frequency shift will be altered. We present our initial attempt to correct for this effect by modeling the existing beam-pipe using CST Microwave Studio(R) to obtain a more realistic electric field distribution. This correction is then applied to data taken with beam at several resonant frequencies. The measurements were made at the Cornell Electron Storage Ring (CESR), which has been reconfigured as a test accelerator (CesrTA) providing electron or positron beams ranging in energy from 2 to 5 GeV. PB - JACoW CP - Geneva, Switzerland SP - 1227 EP - 1229 KW - simulation KW - resonance KW - electron KW - synchrotron KW - storage-ring DA - 2015/06 PY - 2015 SN - 978-3-95450-168-7 DO - 10.18429/JACoW-IPAC2015-MOPWI031 UR - http://jacow.org/ipac2015/papers/mopwi031.pdf ER -