Antarctic Jang Bogo Station
MICA-S (Magnetic Induced Coil Array-South)
The Search-Coil Magnetometer (SCM or MICA South) is designed to measure time-varying magnetic fields associated with magnetosphere-ionosphere coupling processes as a ground-based model. The bi-axial instrument provides two-axis magnetic field wave vector data in the Ultra Low Frequency or ULF (1 mHz to 5 Hz) range. The SCM consists of two magnetic sensors with onboard pre-amplifiers, and a control box containing the main analog board and a data acquisition system (DAQ). The two search-coil magnetic sensors are identical and assembled orthogonally (X and Y axis) using a sensor bracket: The X- and Y-axis sensors are oriented along the geomagnetic north-south and east-west direction, respectively. DAQ digitizes data at 10 samples/s (the International System of units rate or SI) with 16-bit resolution. Digitized data are stored on a daily basis in a PC as ASCII files which are accessible via Network Attached Storage (NAS). The resolution and noise level of the magnetometer reach 0.1, 0.07 pT/sqrt Hz at 1 Hz each. The SCM demonstrates its satisfactory performance, detecting geomagnetic pulsations. In the austral summer 2016, this instrument is installed at the Korean Antarctic station, Jang Bogo and has been operated and acquired ULF data.
2. Science objective
Magnetosphere-polar ionosphere⦁upper atmosphere coupling
• To research the propagation of magnetic field waves on the plasmasphere and ionosphere, key information is ULF waves which are well known to play an important role in energy transport and loss in geospace. ULF waves transmitted from the terrestrial magnetosphere are typically observed at high-latitudes. They cover roughly 1 mHz-5 Hz frequency range: the subclass of the ULF wave include Pc1-5 and Pi1-2. Various wave types of the ULF band have different occurrence factors and plasma conditions. The magnetometer is designed to measure Pc1-2 waves and Pi1-2 waves which are typically associated with electromagnetic ion cyclotron (EMIC) waves and substorm activities, respectively.