Sensor for the Concentration of Small Atmospheric Ions for Field Geophysical Observations

The paper presents the results of the analytical and hardware development of a bipolar sensor for the concentration of small atmospheric ions, designed for long-term geophysical field observations. Theoretical estimates of the response function of the sensor are obtained. The dependence of the concentration of small atmospheric ions on the magnitude of the measured current of the aspiration capacitor and ion mobility spectrum is given. Numerical computations of the trajectories of small ions in an aspiration condenser of specified dimensions and geometry are performed. The probability of recording ions depending on their mobility is found. The circuit solutions and algorithms for the functioning of the hardware of the devices are described. Based on the development materials, prototypes of sensors are made. The technical characteristics and recommendations for the use of devices are given. Unlike analogues, the device is resistant to environmental influences. The sensors are tested in laboratory conditions and during the field observations of the electricity of the atmospheric boundary layer. In addition to being used as a part of a ground-based complex for geophysical observations, the developed sensor was used in an instrumental platform for balloon observations aloft. As a result of testing the devices, it was found that the functioning of the sensors is stable and the data are representative.