The formalism of the stopping power for cluster beams was adapted to the stopping power for short electron bunches by using the wake field of a medium characterized by a plasma frequency. It was shown that an electron bunch with the length of the order of attoseconds collectively loses its energy to excite a high-energy density state in the target. The dynamics of intricate molecular and atomic...

We report the first observation of laser seeding of the storage-ring microbunching instability. Above a threshold bunch current, the interaction of the beam and its radiation results in a coherent instability, observed as a series of stochastic bursts of coherent synchrotron radiation (CSR) at terahertz frequencies initiated by fluctuations in the beam density. We have observed that this effect...

The generation of isolated attosecond hard x-ray pulse has been studied under the enhanced self-amplified spontaneous emission (ESASE) scheme with the density and energy modulation of an electron bunch. It is demonstrated in simulation that an isolated attosecond hard x-ray pulse of a high contrast ratio can be produced by adjusting a driver laser wavelength and the energy distribution of an el...

A method is proposed for the calculation of the short-range wake field potentials of an ultra-relativistic bunch passing near some irregularities in a beam pipe. The method is based on the space-time domain integration of Maxwell’s equations using Kirchhoff’s formulation. We demonstrate this method on two cases where we obtain the wake potentials for the energy loss of a bunch traversing an iri...

The behavior of longitudinal wakefields of very short bunches, excited in in multicell accelerating structures has been studied. Computations were performed in structures proposed for future linear colliders (like TESLA, SBLC and NLC) for bunch lengths down to 50 micrometers. The loss factor, which gives the global energy loss of the bunch, and the profile of the wake function, which is of majo...

A ramped electron bunch (i.e. one having a current density which rises linearly from the head to the tail and then drops sharply to zero) has been predicted to be an ideal drive beam for the plasma wake field accelerator due to the large transformer ratio it is capable of generating. A scheme was recently proposed for the creation of a relativistic electron bunch that approximates a ramped curr...

Synchrotron radiation is currently used on the LHC for beam imaging and for monitoring the proton population in the 3 microsecond abort gap. In addition to these existing detectors, a study has been initiated to provide longitudinal density profiles of the LHC beams with a high dynamic range and a 50ps time resolution. This would allow for the precise measurement both of the bunch shape and the...