Seung Yong Kim

Cold electron source with an electron multiplier illuminated by ultraviolet photons.

A cold electron source has been developed using a microchannel plate (MCP) electron multiplier. Primary electron emission is initiated by illumination with ultraviolet photons from a diode. Final electron emission currents of up to 10 μA in continuous wave (CW) mode and 10 mA in pulsed mode have been achieved from a MCP with an active diameter of 5.5 mm. Electron emission generated by UV photons with a wavelength of 260 nm has been shown to be about 30 times more efficient than emission generated by photons with a wavelength of 300 nm. Application of this cold electron source in mass spectrometry is discussed.

Simulation Study to Improve Ion Transmission Efficiency in Mass Spectrometry with a Dual Ion Funnel Ion Source

We performed computer simulations to improve transmission efficiencies of a dual ion funnel system implemented on an FT-ICR MS. We found that the low m/z range from 50 to 150 could be significantly improved by operating the two ion fun- nels at different RF amplitudes. These new operational conditions could be applied to analyze metabolome samples, which require high sensitivity in the m/z range from 50 to 1,000.