Narrow electron beam production and transmission properties with glass capillaries

Transmission of 300-1000 eV electrons through a single cylindrically-shaped glass capillary of Borosilicate glass was studied [1,2]. The capillary had a diameter of $\sim $0.20 mm and a length of $\sim $15 mm. Transmitted electron intensities revealed three distinct regions with different characteristics: (1) for sample tilt angles (with respect to incident beam) less than 1\r{ } the transmission was dominated by the direct beam (no interactions with inner capillary wall), (2) for tilt angles between 1\r{ } and $\sim $3.5\r{ } the majority of transmission was due to Coulombic repulsion by charge deposition at the capillary entrance, and (3) for tilt angles larger than 3.5\r{ } transmission was governed by inelastic scattering and as a result lost energy. Energy dependence and time evolution studies were carried out to seek more insight into the transmission process. \\[4pt] [1] B.S. Dassanayake \textit{et}.\textit{ al}., \textit{Phys. Rev. A }\textbf{81}, 020701(R) (2010). \\[0pt] [2] B.S. Dassanayake \textit{et}.\textit{ al}., \textit{Phys. Rev. A }\textbf{83}, 012707 (2011).