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arXiv · 2412.13482

Near-Infrared noise in intense electron bunches

Sergei Kladov·Sergei Nagaitsev·Alex H. Lumpkin·Jinhao Ruan·Randy M. Thurman-Keup·Andrea Saewert·Zhirong Huang·Young-Kee Kim·Daniel R. Broemmelsiek·Jonathan Jarvis
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Abstract

This article investigates electron bunch density fluctuations in the 1 - 10 $\mu m$ wavelength range, focusing on their impact on coherent electron cooling (CEC) in hadron storage rings. In this study, we thoroughly compare the shot-noise model with experimental observations of optical transition radiation (OTR) generated by a relativistic electron bunch ($\gamma \approx$ 50), transiting an Aluminium metal surface. The bunch parameters are close to those proposed for a stage in an Electron-Ion Collider (EIC), where the bunch size is much larger than the OTR wavelength being measured. Here we present measurements and particle tracking results of both the low-level noise for the EIC bunch parameters and longitudinal space-charge-induced microbunching for the chicane-compressed bunch with coherent OTR enhancements up to 100 times in the various bandwidth-filtered near-infrared (NIR) OTR photodiode signals. We also discuss the corresponding limitations of the OTR method.

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Sergei Kladov, Sergei Nagaitsev, Alex H. Lumpkin, Jinhao Ruan, Randy M. Thurman-Keup, Andrea Saewert, Zhirong Huang, Young-Kee Kim, Daniel R. Broemmelsiek, Jonathan Jarvis. 2024-12-18. Near-Infrared noise in intense electron bunches. https://doi.org/10.1103/c3fd-g5mn

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