title: Direct Observation of Spatiotemporal Dynamics of Short Electron Bunches in Storage Rings.
abstract: In recent synchrotron radiation facilities, the use of short (picosecond) electron bunches is a powerful method for producing giant pulses of terahertz coherent synchrotron radiation. Here we report on the first direct observation of these pulse shapes with a few picoseconds resolution, and of their dynamics over a long time. We thus confirm in a very direct way the theories predicting an interplay between two physical processes. Below a critical bunch charge, we observe a train of identical THz pulses (a broadband Terahertz comb) stemming from the shortness of the electron bunches. Above this threshold, a large part of the emission is dominated by drifting structures, which appear through spontaneous self-organization. These challenging single-shot THz recordings are made possible by using a recently developed photonic time stretch detector with a high sensitivity. The experiment has been realized at the SOLEIL storage ring.
authors.affiliation: Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523 Centre d'Études et de Recherches Lasers et Applications, FR CNRS 2416, Université des Sciences et Technologies de Lille, F-59655 Villeneuve d'Ascq Cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Evain
authors.affiliation: Elettra-Sincrotrone Trieste, Strada Statale 14-km 163,5 in AREA Science Park,34149 Basovizza, Trieste, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Roussel
authors.affiliation: Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523 Centre d'Études et de Recherches Lasers et Applications, FR CNRS 2416, Université des Sciences et Technologies de Lille, F-59655 Villeneuve d'Ascq Cedex, France.
authors.forename: M
authors.initials: M
authors.lastname: Le Parquier
authors.affiliation: Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523 Centre d'Études et de Recherches Lasers et Applications, FR CNRS 2416, Université des Sciences et Technologies de Lille, F-59655 Villeneuve d'Ascq Cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Szwaj
authors.affiliation: Synchrotron SOLEIL, Saint Aubin, BP 34, 91192 Gif-sur-Yvette, France.
authors.forename: M-A
authors.initials: MA
authors.lastname: Tordeux
authors.affiliation: Synchrotron SOLEIL, Saint Aubin, BP 34, 91192 Gif-sur-Yvette, France.
authors.forename: J-B
authors.initials: JB
authors.lastname: Brubach
authors.affiliation: Synchrotron SOLEIL, Saint Aubin, BP 34, 91192 Gif-sur-Yvette, France.
authors.forename: L
authors.initials: L
authors.lastname: Manceron
authors.affiliation: Synchrotron SOLEIL, Saint Aubin, BP 34, 91192 Gif-sur-Yvette, France.
authors.forename: P
authors.initials: P
authors.lastname: Roy
authors.affiliation: Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523 Centre d'Études et de Recherches Lasers et Applications, FR CNRS 2416, Université des Sciences et Technologies de Lille, F-59655 Villeneuve d'Ascq Cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Bielawski