A proposal for a radio-frequency-based streak camera with time resolution less than 100 fs

The authors propose a novel idea for a streak camera whose time resolution is lower than 100 fs. The method replaces the high-voltage sweep component of a conventional streak camera by a TM110-mode RF cavity, which performs a transverse circular sweep of the electron bunch in the streak tube through a rotating magnetic field. The proposed method also allows one to overcome the problem of triggering, which is a serious limitation of conventional streak cameras

Misura del tempo di risposta del GaAs come fotoemettitore

E' stato allestito un apparato sperimentale per la misura del tempo di risposta del GaAs come fotoemettitore, in condizioni di affinita' elettronica negatva. I risultati mostrano un tempo di risposta inferiore a 60 ps (rms), molto piu' rapido di quanto previsto da calcoli basati sull'equazione di diffusione. Questa evidenza sperimentale suggerisce che un fotocatodo di GaAs possa essere installato in un cannone a radiofrequenza con frequenze fino a 800 MHz circa, e lascia intravedere buone opportunita' anche per frequenze maggiori

Measurements of the longitudinal coupling impedences using short electron bunch

The longitudinal coupling impedance in modern storage rings has to be limited to ensure beam stability. To de- termine the real part of the narrow band impedance we suggest to measure the loss factor of the resonant modes using short electron bunch passing through the tested el- ement. This method is also suitable for the measurement of the longitudinal impedances for nonrelativistic particles, that is important for some modern projects of ion storage rings designed to achieve ordered structure in the ion beam. The desired value of relativistic parameter gamma can be chosen by adjusting energy of the electron bunch. The impedance of the fundamental mode of the wall current monitor was measured using 60 ps electron bunch from photogun. The dependence of impedance on beam energy is measured in the range 25-50 kV . Comparison of experimental data with computer simulation is done

The production of short intensive bunches from GaAs photocathode

The installation for length measurements of the electron bunches emitted from GaAs photocathode is constructed. Two methods of bunch length measurements are suggested and applied. The bunch length is calculated on the basis of experimental data. The experimental results are analyzed and compared with results of computer simulations

The GaAs electron source: simulations and experiments

In this paper we calculate electron emission from GaAs photocathodes using the Monte Carlo technique. Typical data of energy spread of the electron beam are presented. For photoenergy ranging from 1.6 to 2.1 eV, the calculated longitudinal and transverse energy spreads are 14.4–78 and 4–14.7 meV respectively. Temporal response measurement of GaAsphotocathodes has been performed. The preliminary results show that the temporal response is faster than 200 ps

Experimental study of the response time of GaAs as a photoemitter

An experimental investigation was carried out to measure the response time of GaAs in negative electron affinity conditions as a photoemitter. During the experiment, the photocathode was excited by a short-pulse (38 ps rms) frequency-doubled Nd:YLF laser. Results show that the rms response time of GaAs is shorter than 40 ps