Dedicated optics with extremely short electron bunches enable synchrotron light sources to generate intense coherent THz radiation. The high degree of spatial compression in this so-called low-alpha optics entails a complex longitudinal dynamics of the electron bunches, which can be probed studying the fluctuations in the emitted terahertz radiation caused by the micro-bunching instability ("bursting"). This article presents a "quasi-instantaneous" method for measuring the bursting characteristics by simultaneously collecting and evaluating the information from all bunches in a multi-bunch fill, reducing the measurement time from hours to seconds. This speed-up allows systematic studies of the bursting characteristics for various accelerator settings within a single fill of the machine, enabling a comprehensive comparison of the measured bursting thresholds with theoretical predictions by the bunched-beam theory. This paper introduces the method and presents first results obtained at the ANKA synchrotron radiation facility.
@article{arxiv.1605.00536,
title = {Fast Mapping of Terahertz Bursting Thresholds and Characteristics at Synchrotron Light Sources},
author = {Miriam Brosi and Johannes L. Steinmann and Edmund Blomley and Erik Bründermann and Michele Caselle and Nicole Hiller and Benjamin Kehrer and Michael J. Nasse and Lorenzo Rota and Manuel Schedler and Patrik Schönfeldt and Marcel Schuh and Markus Schwarz and Marc Weber and Anke-Susanne Müller},
journal= {arXiv preprint arXiv:1605.00536},
year = {2016}
}
Comments
7 pages, 7 figures, to be published in Physical Review Accelerators and Beams