Pulsating dayside aurora in relation to ion upflow events during a northward interplanetary magnetic field (IMF) dominated by a strongly negative IMF B_Y

Abstract

We report a study of ion upflow as seen by the European Incoherent Scatter (EISCAT) Svalbard Radar (ESR), initiated by a rotation from interplanetary magnetic field (IMF) BZ negative to IMF BZ positive, under the influence of a strongly negative IMF BY. We combine ground‐based instruments, such as meridian scanning photometers (MSP), all‐sky imager (ASI) data, and radars, with solar wind data from the Advanced Composition Explorer (ACE) spacecraft and low‐altitude particle precipitation data from the Defense Meteorological Satellite Program (DMSP) F‐13 spacecraft as well as wave data from the Svalbard EISCAT Rocket Study of Ion Outflows (SERSIO) sounding rocket flight. Following a coronal mass ejection, the solar wind data showed high dynamic pressures (up to 20 n Pa) and a strongly varying IMF. The observed ion upflow was seen to be of a pulsed nature and sustained by pulsed soft electron precipitation. The data findings indicated pulsed lobe reconnection as the mechanism funneling energy and momentum down to the northern polar hemisphere.

TRANS4: a new coupled electron/proton transport code – comparison to observations above Svalbard using ESR, DMSP and optical measurements

“…The conditions were very different from one probed region to another. In the all-sky camera images (not shown here, see Simon, 2006, or Lorentzen et al, 2007, the region probed at 100 km by the ESR beam was less active than the upper regions which were also further away from the radar site in the horizontal direction. This is also confirmed by the model and, as shown in Fig.…”

“…An extensive overview of this geophysical event is given by Lorentzen et al (2007). contributed by Dartmouth College, Cornell University, Universities of Oslo and Svalbard (UNIS), Nagoya University, University of Southampton and University of Leicester.…”

SERSIO: Svalbard EISCAT Rocket Study of Ion Outflows

“…To mimic a similar temperature increase as recorded by the thermal particle detector, the local ionosphere would need to support localized flows on the order of 2 -3 km/s. The DMSP F13 satellite drift meter recorded flows on the order of 2 km/s when it crossed (0844-0847 UT) an extension of the same optical emission in which SERSIO flew [Lorentzen et al, 2007]. However, the plasma parameters during the times of the DMSP F13 crossing and the SERSIO flight are quite different, see Figure 2.…”

“…To further investigate low-altitude signatures of ion heating in the cusp/cleft ($750 km), we report here on the 22 January 2004 flight of the SERSIO sounding rocket mission, which included thermal electron and ion instrumentation. A more complete account of the ground-based data for the 22 January 2004 event is given in a paper by Lorentzen et al [2007].…”

Pulsating of the generalized ion and neutral polar winds

“…With regard to pulsating flows, it should be noted that a pulsating ion upflow event was recently observed in the area of the cusp by the European Incoherent Scatter Svalbard Radar (Lorentzen et al, 2007). The pulsating ion outflow, which lasted for about 1 h, occurred after a northward turning of the IMF.…”