Schade, U.; Kuske, P.; Lee, J.; Marchetti, B.; Ortolani, M.: Cross-Correlation of THz Pulses from the Electron Storage Ring BESSY II. Condensed Matter 52 (2020), p. 24/1-12
10.3390/condmat5020024
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Abstract:
Coherent synchrotron radiation from an electron storage ring is observed in the THz spectral range when the bunch length is shortened down to the sub-mm-range. With increasing stored current, the bunch becomes longitudinally unstable and modulates the THz emission in the time domain. These micro-instabilities are investigated at the electron storage ring BESSY II by means of cross-correlation of the THz fields from successive bunches. The investigations allow deriving the longitudinal length scale of the micro bunch fluctuations and show that it grows faster than the current-dependent bunch length. Our findings will help to set the limits for the possible time resolution for pump-probe experiments achieved with coherent THz synchrotron radiation from a storage ring.