The Columbia University sub-micron charged particle beam

The Columbia University Sub-micron Charged Particle Beam.

A lens system consisting of two electrostatic quadrupole triplets has been designed and constructed at the Radiological Research Accelerator Facility (RARAF) of Columbia University. The lens system has been used to focus 6-MeV (4)He ions to a beam spot in air with a diameter of 0.8 µm. The quadrupole electrodes can withstand voltages high enough to focus (4)He ions up to 10 MeV and protons up t...

Pyroelectric deflector of charged particle beam

A new type deflector of a charged particle beam based on pyroelectric crystals is proposed and demonstrated experimentally. The transverse electric field arises in the gap between two pyroelectric crystals in vacuum because of the pyroelectric effect appearing when a temperature gradient is applied to both crystals. In a proof-of-principle experiment, we demonstrated deflection of a low-energy ...

Quantum theory of charged-particle beam optics

Charged-particle beam optics, or the theory of transport of charged-particle beams through electromagnetic systems, is traditionally dealt with using classical mechanics. Though the classical treatment has been very successful, in designing and working of numerous charged-particle optical devices, it is natural to look for a deeper understanding based on the quantum theory, since any system is ...

Fine PM and sub-micron particle number concentrations

Unsteady Of Deposition of Sub-Micron Charged Particles in the Human Respiratory Tract

The electrostatic charge carried by aerosol particles greatly enhances their deposition in the airways. Electrifications normally occur in aerosol generating process. It has been long suspected that the unipolar charge carried by the particles may have a significant in the deposition efficiency of the particles in the human respiratory tract during breathing. Deposition of charged particles in ...