Anthony Y. Lui

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[1] We compare the timing and spatial extent of dipolarization with auroral breakup by using magnetic field data (1-min time resolution) from GOES 8 and GOES 9 and global auroral images (37-s frame rate) from the Polar ultraviolet imager. We survey the entire year of 1997 data and obtain 32 unambiguous dipolarization events that had ionospheric footprints(More)
[1] To understand the large-scale plasma sheet thermodynamics, we have used Geotail data and a formula for estimating flux tube volume V to investigate statistically the equatorial distributions of PV and nV for slow flowing plasma in the nightside plasma sheet and compare them with the physical bases of ideal MHD and the Rice Convection Model (RCM). We(More)
One month’s worth of POLAR UVI data were subjected to a ‘‘blob’’ analysis to determine the statistical dynamics of substorm features observed in the LBHL band (152-188 nm). Adapted from similar DoD analyses of target images, the analysis consists of finding, on a frame-by-frame basis beginning at substorm onset, the following aspects of an individual(More)
ion with a customized service view name that is more intuitive. A work order can be created via an eSM-provided Web-based user interface or a published Common Object Request Broker Architecture (CORBA*) interface in OMG Interface Definition Language (IDL).* The eSM also supports a bulk provisioning capability that enables service providers to add large(More)
[1] We have statistically analyzed Geotail data to investigate the processes that result in a plasma sheet that is denser under a prolonged northward than southward interplanetary magnetic field (IMF) period. The observations show that the change of number density with the IMF conditions is mainly due to the changes of particle number per unit magnetic flux(More)
We examine evolution of the cross-tail current during substorm current disruption/dipolarization using observations from two satellites in the near-Earth magnetotail at the downtail distances of 8–9RE. By choosing times when these two satellites are separated, mainly in the north–south distance in the tail current sheet, precise determination of current(More)
[1] In this paper we present a data-derived model of relativistic electron flux at geosynchronous orbit. The model is driven by multiple solar wind and magnetospheric inputs and combines the deterministic approach of nonlinear dynamics with conditional probability consideration. The model is used for one-day predictions of daily flux maxima for the years(More)
A linear analysis is performed to investigate he kinetic ross-field streaming instability in the Earth's magnetotail neutral sheet region. Numerical solution of the dispersion equation shows that the instability can occur under conditions expected for the neutral sheet just prior to the onset of substorm expansion. The excited waves are obliquely(More)