Collaborative Research: Continued Study of Ultra Low Frequency (ULF) Waves at Cusp Latitudes on Svalbard to Probe Earth's Space Environment

点击翻译按钮获取中文摘要

A large array of ground based instruments has been installed on the Svalbard archipelago in Norway. Svalbard is frequently on polar cusp field lines that map to the outer boundary of the Earth's magnetosphere where it interacts with the solar wind and interplanetary magnetic field (IMF). This proposal has two parts: One part is for support for the continued operation of and processing data from an array of four search coil magnetometers (induction antennas). The second part is to carry out analysis of data from these four instruments. Svalbard is the only place in the northern hemisphere where polar cusp field lines can be observed for extended periods in darkness at noon. In addition to the four search coil magnetometers auroral imagers and photometers, several radars (EISCAT, SPEAR and SuperDarn) and the northernmost fluxgate magnetometers of the IMAGE chain are located on Svalbard. This makes Svalbard an excellent place to carry out observations of ionospheric phenomena on magnetic field lines that map to the magnetopause. Three main types of studies using the data from the search coils and other instruments are:a.) Make a concentrated effort to understand the observations of Pc 1-2 waves in the cusp and their effect on radiation belt dynamics. In the Pc 1-2 frequency range electromagnetic ion cyclotron waves (EMIC) are thought to interact resonantly with MeV electrons in the radiation belts. The waves and radiation belt dynamics and the persistence of waves (sometimes seen for days) will be studied as well as waves associated with auroral precipitation. b.) Probe the Ionosphere Alfvén Resonator (IAR) by using the Space Plasma Exploration by Active Radar (SPEAR) heater facility in conjunction with the EISCAT radar. The IAR is a region in the ionosphere bounded by the F or E region at lower altitudes and by a peak in the Alfvén velocity at higher altitudes. This research will characterize the quality factor (Q) of the IAR. The quality factor relates the energy stored in the resonator with the energy dissipated. If the IAR is driven long enough the energy contained in the resonator will be proportional to Q. By controlling the input energy from the SPEAR heater they will be able to determine Q. c.) Investigate the properties of PC3-4 waves at very high latitudes. In this study SuperDARN radar will be used along with the search coils to determine the intensity of PC 3-4 as a function of position with respect to the cusp. The goal will be to determine how these ULF waves reach the high latitude ionosphere. The data from the four closely space magnetometers are very valuable for a number of space physics studies. The team will make the data available to the scientific community through the NASA Virtual Observatories. This proposal will support a graduate student at the University of New Hampshire and an undergraduate researcher at Augsburg College.