Balloon-borne ion sampling package

Area of Science:

• Atmospheric science
• Astrochemistry
• Ion physics

Background:

• Stratospheric ion composition is crucial for understanding atmospheric chemistry and aerosol formation.
• Previous methods for in-situ stratospheric ion analysis faced limitations in mass range and sensitivity.

Purpose of the Study:

• To design and construct a mass filter package for in-situ measurement of stratospheric positive and negative ions.
• To analyze the mass-to-charge ratio of ions in the stratosphere (1-150 amu).
• To investigate the presence of specific ion species, such as hydrated protons.

Main Methods:

• Development of a quadrupole mass filter with a 1-150 amu range, capable of fixed peak or continuous sweep operation.
• Integration of ion counting, ambient condition sensors (temperature, pressure, conductivity), and cosmic ray detectors.
• Utilizing a valved orifice for atmospheric sampling designed to minimize contamination.
• Employing on-board data recording and telemetry for real-time analysis.

Main Results:

• Successful design and construction of a stratospheric mass filter package for positive ion (PI) and negative ion (NI) detection.
• Demonstrated capability for individual ion counting across a wide mass range (1-150 amu).
• Preliminary flight data indicate evidence for the existence of hydrated protons in the stratosphere.

Conclusions:

• The developed mass filter package is a viable tool for in-situ stratospheric ion composition studies.
• The detection of hydrated protons suggests their potential role in stratospheric ion chemistry.
• Further analysis of data from this instrument can enhance our understanding of stratospheric processes.