Study of Coherent Tune Shift Caused by Electron Cloud in Positron Storage Rings
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چکیده
We discuss the transverse betatron tune shift of the coherent dipole motion of a beam interacting with an electron cloud. A positron beam which passes through a frozen charge distribution experiences an electric field, which shifts its tune in the positive direction. The electrons in the actual cloud are not frozen, but move during the bunch passage. Thus, the electron distribution varies due to the interaction with the beam and it is “soft”. We study the dipole tune shift of the beam interacting with such a “soft” charge distribution.
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تاریخ انتشار 2001