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arXiv · 2412.00463

Beam-cavity interactions in the rapid cycling synchrotron chain of the future muon collider

Leonard Thiele·Fabian Batsch·Rama Calaga·Heiko Damerau·Alexej Grudiev·Ivan Karpov·Ursula van Rienen
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Abstract

The International Muon Collider Collaboration (IMCC) is engaged in a design study for a future facility intended to collide muons. Subsequent to the initial linear acceleration, the counter-rotating muons and anti-muons are accelerated in a chain of rapid cycling synchrotrons (RCS) up to the multi-TeV collision energy. To maximise the number of muons available in the collider, it is essential to exploit the time dilation of the muon lifetime by employing a large accelerating gradient. The 1.3 GHz TESLA cavity serves as the baseline for the RCS chain. Considering the high bunch population and the small aperture of the cavity, the resulting beam-induced voltage per bunch passage is considerable, resulting in a substantial perturbation of the cavity voltage for subsequent bunch passages. In this contribution, the effects of beam loading during the acceleration cycle on the muons are calculated with the objective of determining the optimum parameters for minimising the cavity voltage transients. The interaction of the induced voltages, considering the counter-rotating beams, is studied.

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Leonard Thiele, Fabian Batsch, Rama Calaga, Heiko Damerau, Alexej Grudiev, Ivan Karpov, Ursula van Rienen. 2025-04-10. Beam-cavity interactions in the rapid cycling synchrotron chain of the future muon collider. https://arxiv.org/abs/2412.00463

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