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The description of physical processes with many-particle systems is a key approach to the modeling of numerous physical systems. For example in storage rings, where ultrarelativistic particles are agglomerated in dense bunches, the modeling and measurement of their phase-space distribution is of paramount importance: at any time the phase-space distribution not only determines the complete space-time evolution but also provides fundamental performance characteristics for storage ring operation. Here, we demonstrate a non-destructive tomographic imaging technique for the 2D longitudinal phase-space distribution of ultrarelativistic electron bunches. For this purpose, we utilize a unique setup, which streams turn-by-turn near-field measurements of bunch profiles at MHz repetition rates. To demonstrate the feasibility of our method, we induce a non-equilibrium state and show that the phase-space distribution microstructuring as well as the phase-space distribution dynamics can be observed in great detail. Our approach offers a pathway to control ultrashort bunches and supports, as one example, the development of compact accelerators with low energy footprints. [ABSTRACT FROM AUTHOR]

The article presents a study which examines a high-repetition-rate pump-probe based on the asynchronous sampling approach. It states that during the synchrotron ANKA, the low-alpha mode can be used for a time resolution down to the picosecond limit for the time domain sampling of the coherent terahertz emission as well as for hard X-ray pump-probe experiments. It presents examples of phonon dynamics of semiconductors and shows that a synchronization of better than 1 ps is achieved.

In March 2005 a superconducting cold-bore undulator was installed in ANKA (ANSTROEM SOURCE IN KARLSRUHE) and since that time has been in operation. The purpose of the installation was to evaluate if such a device can be operated in a heavy duty synchrotron radiation user facility like ANKA without problems. In order to demonstrate this the generated spectra were measured and the heat load induced by the beam was investigated. It was shown that the heat deposited by the beam in the 8 mm gap is less than 1 W per 100 mA at 2.5 GeV and can be cooled by cryocoolers. Finally, reference is made to the spectra produced by sub-picosecond X-rays using a special ANKA optics. [ABSTRACT FROM AUTHOR]

Schottky diodes are well-known nonlinear elements allowing for effective detection and mixing of electromagnetic radiation in the range throughmicrowave to terahertz. Although less sensitive than their superconducting counterparts, they generally do not require cooling that makes them the devices of choice for applications where the ultimate sensitivity is not needed. In the emerging field of terahertz technology, there is a long-time quest for cheap and handy detectors for laboratory use, as well as for serial compact and midsize instruments. We describe the use of a quasi-optically coupled zero-bias planar Schottky-diode detector for monitoring picosecond pulses of synchrotron terahertz radiation and weak continuous-wave emission from an array of Josephson junctions. [ABSTRACT FROM AUTHOR]

In recent and future synchrotron radiation facilities, relativistic electron bunches with increasingly high charge density are needed for producing brilliant light at various wavelengths, from X-rays to terahertz. In such conditions, interaction of electron bunches with their own emitted electromagnetic fields leads to instabilities and spontaneous formation of complex spatial structures. Understanding these instabilities is therefore key in most electron accelerators. However, investigations suffer from the lack of non-destructive recording tools for electron bunch shapes. In storage rings, most studies thus focus on the resulting emitted radiation. Here, we present measurements of the electric field in the immediate vicinity of the electron bunch in a storage ring, over many turns. For recording the ultrafast electric field, we designed a photonic time-stretch analog-to-digital converter with terasamples/second acquisition rate. We could thus observe the predicted link between spontaneous pattern formation and giant bursts of coherent synchrotron radiation in a storage ring. [ABSTRACT FROM AUTHOR]