Due to various upstream beam manipulations, the longitudinal bunch shape at the interaction point of the Stanford Linear Collider (SLC) is highly non-Gaussian. In this paper, we report beam-beam simulations with realistic longitudinal bunch shapes for the present SLC parameters and for the SLC-2000 luminosity upgrade. The simulation results allow us to estimate the luminosity enhancement due to...

We have developed a two-macroparticle bunch to explore the longitudinal beam dynamics through various components of the Fermilab/NICADD photoinjector. Such a two-macroparticle bunch is generated by splitting the ultraviolet pulse from the photocathode drive laser. The presented method allows the exploration of radiofrequency-induced compression in the 1.625 cell rf-gun and the booster cavity. I...

In this paper, We investigate numerically the development of self-modulation instability (SMI) with electron bunch parameter available at Accelerator Test Facility (ATF) of Brookhaven National Laboratory (BNL). The results show that the long bunch drives wakefields with periods one to one fifth of the bunch length in plasmas with various densities. Both 50 pC and 1 nC electron bunches are inves...

At the Metrology Light Source (MLS) [1] owned by the Physikalisch-Technische Bundesanstalt (PTB) the bunch length can be varied by more than two orders of magnitude [2]. The bunch length manipulation is achieved by varying different machine parameters, such as RF-voltage amplitude up to 500 kV and the momentum compaction factor α over three orders of magnitude. The subject of this article is th...

Single-pass free electron lasers require high peak currents from ultra-short electron bunches to reach saturation and an accurate measurement of bunch length and longitudinal bunch profile is necessary to control the bunch compression process from low to high beam energy. The various state-of-the-art diagnostics methods from ps to fs time scales using coherent radiation detection, RF deflection...

The operation and parameters of Bunch Shape Monitors using coherent transformation of time structure of an analyzed beam into a spatial one of low energy secondary electrons emitted from a wire target is influenced by the characteristics of a beam under study. The electromagnetic field of a bunch disturbs the trajectories of secondary electrons, thus resulting in a degradation of phase resoluti...

A strong horizontal instability limits the maximum positron current storable in the DAFNE Phi-Factory. A powerful feedback system makes it possible to store and put in collision more than 1300 mA of positron current in 105-109 bunches. Nevertheless, a much higher current (>2.4A) has been successfully stored in the twin electron ring. Measurements have been carried out to understand the positron...

The transfer of energy from the driving beam to the trailing beam in the plasma wake field accelerator is studied in computer simulations. We show that with an asymmetric current distribution in the driving bunch, trailing particles can gain energies up -to 4 1 + k2Z2Aymc2 P , where 2 is the bunch length, and A,ymc2 the average energy loss of driving electrons. Due to the relative phase slippag...

Time-correlated single-photon counting (TCSPC) techniques have been used for bunch purity measurement since the Advanced Photon Source (APS) started operations. Recent improvements of the monitor have increased the signal-to-noise ratio and dynamic range to about 100 billion. Resolution improvements of commercial TCSPC components to under 50 ps FWHM allowed us to measure the longitudinal profil...

The analytical treatment previously described [1] has been extended to include the important effect of magnetic quadrupole transverse displacements, the chromatic variation of the magnetic focusing, the energy spread along the bunch and possible microwave quadrupoles, the last two in relation to BNS damping. Both, the longitudinal and transverse equations of motion are solved, the second by usi...