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arXiv · 1904.09195

Smoothing of the slowly extracted coasting beam from a synchrotron

Rahul Singh·Peter Forck·Stefan Sorge
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Abstract

Slow extraction of beam from synchrotrons or storage rings as required by many fixed target experiments is performed by controlled excitation and feeding of a structural lattice resonance. Due to the sensitive nature of this resonant extraction process, the temporal structure of the extracted beam is modulated by the minuscule current fluctuations present on the quadrupole magnet power supplies. Such a modulation lead to pile-ups in detectors and a significant reduction in accumulated event statistics. This contribution proposes and experimentally demonstrates that by an introduction of further modulation on quadrupole currents with a specific amplitude and frequency, the inherent power supply fluctuations are mitigated leading to a smoothening of the beam temporal structure. The slow extraction beam dynamics associated with this method are explained along with the operational results.

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Rahul Singh, Peter Forck, Stefan Sorge. 2019-04-19. Smoothing of the slowly extracted coasting beam from a synchrotron. https://doi.org/10.1103/physrevapplied.13.044076

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