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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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Non-radioactive electron source with nanosecond pulse modulation for atmospheric pressure chemical ionization
Erik Bunert1, Marc Berger1, Ansgar T Kirk1
1Department of Sensors and Measurement Technology, Institute of Electrical Engineering and Measurement Technology, Leibniz University Hannover, Appelstr. 9A, 30167 Hannover, Germany.
The Review of Scientific Instruments
|November 30, 2019
Summary
Researchers developed a compact, nonradioactive electron source for ion mobility spectrometers (IMSs). This pulsed electron source achieves 23 ns pulse widths, enhancing trace gas detection capabilities.
Area of Science:
- Analytical Chemistry
- Instrumentation Science
Background:
- Ion mobility spectrometers (IMSs) are vital for sensitive trace gas detection.
- Traditional IMS often rely on radioactive sources for ionization.
- A compact, nonradioactive electron source was previously developed for IMS applications.
Purpose of the Study:
- To characterize and optimize a pulsed, nonradioactive electron source for IMS.
- To investigate the impact of short electron pulses on ion formation dynamics.
- To enhance the analytical performance of IMS through controlled ionization.
Main Methods:
- Development of a novel measurement setup for detecting nanosecond electron pulses.
- Optimization of geometric parameters and control electronics for the electron source.
- Investigation of spatial ion distribution as a function of operating parameters (electron energy, ionization time).
Main Results:
- Achieved extremely short electron pulse widths down to 23 ns.
- Demonstrated controlled electron emission current in pulsed mode.
- Characterized nanosecond electron pulses with amplitudes in the nanoampere range.
- Investigated spatial ion distribution influenced by electron energy and ionization time.
Conclusions:
- The pulsed nonradioactive electron source offers precise kinetic control over ion formation in IMS.
- Short pulse widths minimize competing ionization processes, improving analytical performance.
- This technology advances ultrasensitive trace gas detection without radioactive materials.
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