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arXiv · 1904.10188

Beam blowup due to synchro-beta resonance with/without beam-beam effects

Katsunobu Oide·Dima El Khechen
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Abstract

A blowup of vertical emittance has been observed in particle tracking simulations with beam-beam and lattice misalignments. It was somewhat unexpected, since estimation without lattice errors did not predict such a blowup unless a residual vertical dispersion at the interaction point (IP) is larger than a certain amount. Later such a blowup has been seen in a tracking of lattices without beam-beam effect. A possible explanation of the blowup is given by a Vlasov model for an equilibrium of quadratic transverse moments in the synchrotron phase space. This model predicts such a blowup as a synchro-beta resonance mainly near the first synchrotron sideband of the main x-y coupling resonance line.

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Katsunobu Oide, Dima El Khechen. 2019-04-23. Beam blowup due to synchro-beta resonance with/without beam-beam effects. https://arxiv.org/abs/1904.10188

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