Time-synchronized continuous wave laser-induced fluorescence on an oscillatory xenon discharge

Area of Science:

• Atomic Physics
• Plasma Diagnostics
• Optical Spectroscopy

Background:

• Accurate time-resolved measurements in oscillating plasmas are challenging.
• Laser-induced fluorescence (LIF) is a powerful diagnostic technique.
• Synchronizing LIF to plasma current oscillations requires specialized methods.

Purpose of the Study:

• To develop a novel method for time-synchronizing LIF measurements to a 60 Hz xenon discharge current.
• To investigate the temporal dynamics of the lower state population in the xenon discharge.
• To analyze the frequency response of the xenon atomic transition.

Main Methods:

• Utilized a continuous wave laser for LIF excitation.
• Implemented a sample-hold circuit to capture signals at specific current phases.
• Employed a lock-in amplifier to extract the synchronized fluorescence signal from background noise.
• Measured the 6s'[1/2](1)(0)-6p'[3/2](2) xenon atomic transition at 834.68 nm.

Main Results:

• Successfully synchronized LIF measurements to the 60 Hz xenon discharge current.
• The time evolution of the lower state population was accurately determined.
• Observed that the lower state population oscillates at 120 Hz.

Conclusions:

• The developed method enables precise time-resolved LIF diagnostics in oscillating plasmas.
• The xenon lower state population exhibits a 120 Hz oscillation frequency.
• This technique provides insights into the dynamic behavior of discharge lamps.