A ground-based instrument suite for integrated high-time resolution
measurements of pulsating aurora with Arase
Abstract
A specialized ground-based system has been developed for simultaneous
observations of pulsating aurora (PsA) and related magnetospheric
phenomena with the Arase satellite. The instrument suite is composed of
1) six 100-Hz sampling high-speed all-sky imagers (ASIs), 2) two 10-Hz
sampling monochromatic ASIs observing 427.8 and 844.6 nm auroral
emissions, 3) Watec Monochromatic Imagers, 4) a 20-Hz sampling
magnetometer and 5) a 5-wavelength photometer. The 100-Hz ASIs were
deployed in four stations in Scandinavia and two stations in Alaska,
which have been used for capturing the main pulsations and quasi 3 Hz
internal modulations of PsA at the same time. The 10-Hz sampling
monochromatic ASIs have been operative in Tromsø, Norway with the 20-Hz
magnetometer and the 5-wavelength photometer. Combination of these
multiple instruments with the European Incoherent SCATter (EISCAT) radar
enables us to reveal the energetics/electrodynamics behind PsA and
further to detect the low-altitude ionization due to energetic electron
precipitation during PsA. In particular, we intend to derive the
characteristic energy of precipitating electrons during PsA by comparing
the 427.8 and 844.6 nm emissions from the two monochromatic ASIs. Since
the launch of the Arase satellite, the data from these instruments have
been examined in comparison with the wave and particle data from the
satellite in the magnetosphere. In the future, the system will be
utilized not only for studies of PsA but also for other categories of
aurora in close collaboration with the planned EISCAT_3D project.