Energy Spectrum of an Electron Cloud with Short Bunch
نویسندگان
چکیده
The transverse instability in a beam and the blow-up in its size caused by an electron cloud become increasingly important in high-intensity accelerators. The electron cloud builds up through beam-induced multipacting. We investigated the energy spectrum of an electron cloud with short bunch using particle simulation. A "stop-band" structure is found and a model is suggested to explain and to describe this phenomenon. The number of stop-bands depends only upon the beam (bunch spacing and intensity) and the radius of the vacuum pipe. The electronenergy spectrum provides useful information for understanding multipacting and measuring the electron’s energy.
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