Related papers: Strong RF focusing for luminosity increase: short …
A luminosity of a circular collider can be increased by squeezing the bunch length at the interaction point (IP). A natural way to decrease the bunch length is to decrease the momentum compaction factor and/or to increase the RF voltage.…
At present, the PEP-II bunch length and vertical beta function at the Interaction Point (IP) are about of the same size. To increase luminosity, it is planned to gradually reduce the IP beta function. For the maximum effect, bunch length…
Two devices for subwave length focusing of light are explored. The first one is a thin film of a well reflecting metal which the converging beam of surface plasmons with a wave number $h>>\omega_0/c$ is excited on. The waist of this beam…
Perfect lensing using negative refractive index materials and radiationless electromagnetic interference both provide extreme subwavelength focusing by "amplifying" evanescent wave components that are usually lost. This paper provides a…
The high-performance operation of fourth-generation synchrotron light sources critically depends on harmonic cavities (HCs) to alleviate statistical collective effects through bunch lengthening. Active HCs are preferred over passive ones…
The ultrafast and ultracold electron source, based on laser cooling and trapping of an atomic gas and its subsequent near-threshold photoionization, is capable of generating electron bunches with a high transverse brightness at energies of…
We consider a scheme to generate sub-picosecond electron bunch in the photocathode rf gun by improving the acceleration gradient in the gun, suitably tuning the bunch charge, the laser spot size and the acceleration phase, and reducing the…
The development of effective focusing schemes for positron bunches in plasma accelerators remains a significant challenge, as nonlinear regimes fail to create stable focusing channels for positrons. This work presents a method for focusing…
We describe a simple mechanism to transform bunches with matched longitudinal phase-space distributions from one RF system to a matched distribution of a second RF system operating on a different harmonic and with a different accelerating…
Generating high-brightness relativistic electron bunches with few-femtosecond duration, while simultaneously achieving few-fs synchronization with ultrafast lasers, remains an outstanding challenge at the frontier of accelerator physics and…
Diffraction limits the behaviour of light in optical systems and sets the smallest achievable line width at half the wavelength. With a novel subwavelength plasmonic lens to reduce the diffraction via an asymmetry and to generate and…
A novel method of producing intense short wavelength radiation from relativistic electrons is described. The electrons are periodically bunched at the wavelength of interest enabling in-phase super-radiant emission that is orders of…
In electron storage rings, it is possible to increase the bunch length by applying phase modulation to the radio frequency accelerating field by choosing appropriate parameters for the modulation. Such a bunch lengthening effect improves…
A pair of superconducting transverse deflecting RF cavities has been studied in the QBA low emittance lattices of the 3 GeV TPS for generating ultra short X-ray pulses. Three configurations with different locations for the two cavities in a…
A hierarchy of statistics of increasing sophistication and accuracy is proposed, to exploit an interesting and fundamental arithmetic structure in the photon bunching noise of incoherent light of large photon occupation number, with the…
We propose to use ultra-high intensity laser pulses with wavefront rotation (WFR) to produce short, ultra-intense surface plasma waves (SPW) on grating targets for electron acceleration. Combining a smart grating design with optimal WFR…
Radio-frequency (RF) systems deliver the power to change the energy of a charged particle beam, and they are integral parts of linear and circular accelerators. A longitudinal electrical field in the direction of the beam is generated in a…
Recent studies have shown that the prospects for significantly increasing bunch intensities in the LHC for the luminosity upgrade (HL-LHC) may be severely limited by the available cryogenic cooling capacity and the electron-cloud (EC)…
We present the results of multi-objective genetic algorithm optimizations of a potential single shot ultra fast electron diffraction beamline utilizing a 100 MV/m 1.6 cell normal conducting rf (NCRF) gun, as well as a 9 cell 2pi/3 bunching…
Plasmonic nano-antennas can focus light to nanometre length-scales providing intense field enhancements. For the tightest optical confinements (0.5-5 nm) achieved in plasmonic gaps, the gap spacing, refractive index, and facet width play a…