First real-time studies of ultra-fast processes by single-bunch imaging at the European Synchrotron Radiation Facility are reported. By operating the storage ring of the ESRF in single-bunch mode with its correspondingly increased electron bunch charge density per singlet, the polychromatic photon flux density at insertion-device beamlines is sufficient to capture hard X-ray images exploiting t...

121301-1 The focusing effects of a 1.4 m long, 0–2 1014 cm 3 plasma on a single 28.5 GeVelectron bunch are studied experimentally in the underdense or blowout regime, where the beam density is much greater than the plasma density. As the beam propagates through the plasma, the density of plasma electrons along the incoming bunch drops from the ambient density to zero leaving a pure ion channel ...

We report the observation of multiparticle coherent emission in the very far infrared from bunched electrons in an electron storage ring. The emission occurs in quasi-periodic bursts, and only when the electron beam current exceeds a threshold value, suggesting an instability-driven modulation of the electron bunch density. For the operating conditions reported, the spectral content of the cohe...

Grapevine cultivar can affect susceptibility to Lobesia botrana and Eupoecilia ambiguella with important implications on control strategies. A four-year study was carried out in north-eastern Italy on 10 cultivars (Cabernet Sauvignon, Carménère, Chardonnay, Merlot, Refosco dal Peduncolo Rosso, Rhine Riesling, Sauvignon Blanc, Terrano, Tocai Friulano and Verduzzo Friulano) grown in the same vine...

Many vineyards all over the world can easily produce high potential alcohol levels, but the importance of the sugar content in berries has been changing over the past few years. The objective of this work was to reduce the sugar and pH of the grapes, delay berry ripening by decreasing the ratio between the leaf area and yield, perform an intense trimming treatment after berry set and establish ...

In the E-157 experiment now being conducted at the Stanford Linear Accelerator Center, a 30 GeV electron beam of 2310 electrons in a 0.65-mm-long bunch is propagated through a 1.4-m-long lithium plasma of density up to 2310 e/cm. The initial beam density is greater than the plasma density, and the head of the bunch expels the plasma electrons leaving behind a uniform ion channel with transverse...

The amplitude of Parametric X-ray radiation emitted coherently by a bunch of electrons crossing a crystal (CPXR) is calculated. When the bunch density is modulated with a longitudinal period close to the X-ray wavelenght, constructive many-electron interferences enhance the intensity by Nb × |F (K)| , where Nb is the number of electrons in the bunch, F (K) the bunch form factor and K a specifie...

LONG BUNCHES M. Blaskiewicz , BNL 911B, Upton, NY 11973-5000, USA Abstract For long bunches, trailing edge multi-pacting causes the electron cloud density at the trailing edge of the bunch to be significantly larger than the cloud density during the early and central portions of the bunch. The effective wakefield is modeled and compared with hand estimates. Instabilty simulations, which include...

* The work is supported by DOE SBIR No. DE-FG03-96ER82213. Abstract Synchronous wakefields in a dispersive waveguide are formulated in a general form. The fundamental role of group velocity in wakefield propagation, calculation of attenuation, amplitudes, form-factors and loss-factors is demonstrated for single-bunch and multi-bunch train. Waveguide adiabatic tapering and bunch density variatio...