Guiding effect on strong beam electrons in tapered SiO2 capillary

The transmission of strong beam electrons (1 to 10 μA) through a tapered SiO2 capillary was investigated. The time dependence of the total transmitted fraction and one-dimension angular distribution of transmitted electrons were experimentally studied. The result indicates that, the transmitted electrons have the Gaussian distribution and good temporal stability; the transmitted fraction decreases with the incident energy in a negative exponential manner, and this dependence is supported by the guiding effect model．