A5055101902- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- Astro and Planetary Science
- Planetary Science and Exploration
- Earthquake Detection and Analysis
- Magnetic Field Sensors Techniques
- Magnetic confinement fusion research
- Dust and Plasma Wave Phenomena
- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Space Satellite Systems and Control
- Diamond and Carbon-based Materials Research
- Characterization and Applications of Magnetic Nanoparticles
- Atomic and Subatomic Physics Research
- Methane Hydrates and Related Phenomena
- Spacecraft and Cryogenic Technologies
- Atmospheric Ozone and Climate
- Geophysics and Gravity Measurements
- Distributed and Parallel Computing Systems
- Electromagnetic Launch and Propulsion Technology
Umeå University
2016-2021
Charles River Laboratories (Netherlands)
2018
Magnetic holes (MHs), with a scale much greater than \r{ho}i (proton gyroradius), have been widely reported in various regions of space plasmas. On the other hand, kinetic-size magnetic (KSMHs), previously called small size (SSMHs), order magnitude or less only Earth's magnetospheric plasma sheet. In this study, we report such KSMHs magnetosheath whereby use measurements from Magnetospheric Multiscale (MMS) mission, which provides three-dimensional (3D) particle distribution resolution...
Abstract Magnetic holes (MHs), characteristic structures where the magnetic field magnitude decreases significantly, have been frequently observed in space plasmas. Particularly, small size (SSMHs) which scale is less than or close to proton gyroradius are recently detected magnetospheric plasma sheet. In this study of Cluster observations, by timing method, minimum directional difference (MDD) and spatiotemporal (STD) we obtain propagation velocity SSMHs flow frame. Furthermore, based on...
Detection of hypervelocity impacts on a spacecraft body using electric field instruments has been established as new method for monitoring dust grains in our solar system. Voyager, WIND, Cassini, and STEREO have shown that this technique can be complementary to conventional detectors. This approach uses fast short time changes the potential generated by impacts, which detected monopole pulse measured field. The shape duration strongly depend parameters ambient plasma environment. fact is...
Abstract Dust impact detection by electric field instruments is a relatively new method. However, the influence of dust impacts on measurements not completely understood and explained. A better understanding very important for reliable identification, especially in environments with low rate. Using data from Earth‐orbiting Magnetospheric Multiscale mission (MMS) spacecraft, we present study various pulses detected simultaneously multiple antennas monopole (probe‐to‐spacecraft potential...
Abstract We present the first study of dust impact events on one Earth‐orbiting Cluster satellites. The were identified in measurements wide band data (WBD) instrument board satellite operating monopole configuration. Since 2009 is this configuration due to loss three electric probes and therefore measuring potential between only antenna spacecraft body. Our shows that WBD 1 able detect pulses generated by impacts discusses four such events. presence instrumental effects, intensive natural...
Abstract We use Geotail, Cluster, and Time History of Events Macroscale Interactions during Substorms data over 15 years (1995–2009) to statistically investigate convective ion flows ( V ⊥ x y <200 km/s) in the magnetotail plasma sheet under influence a clearly nonzero dawn‐dusk interplanetary magnetic field (IMF B ). find that IMF causes an interhemispheric asymmetry flows, which depends on direction . On average, one hemisphere is dominated by flow component, oppositely directed...
Abstract Here we present some unique observations of reconnection at a quasi‐perpendicular bow shock as an interplanetary directional discontinuity (DD) is crossing it simultaneously with the Magnetospheric Multiscale (MMS) mission. There are no burst data, but available data show indications ongoing southward MMS: bifurcated current sheet signatures Hall magnetic and electric fields, normal fields indicating connection between two reconnecting regions, field‐aligned currents E · J >0...
Abstract Using plasma sheet data from Cluster 1 spacecraft 2001 till 2011, we statistically investigate oscillatory signatures in the bulk flow. These periodic oscillations are compared to high‐speed and quiet flows. Periodic observed approximately 8% of time, while flows around 0.5% 12% respectively. We remark that can roughly occur everywhere for x gsm <−10 R E | y |<10 , mainly toward flanks this region =− 10 . The relation between geomagnetic solar activity occurrence is...
Abstract Evidence suggests that a non-zero dawn–dusk interplanetary magnetic field (IMF $$B_y$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>B</mml:mi> <mml:mi>y</mml:mi> </mml:msub> </mml:math> ) can cause rotation of the cross-tail current sheet/neutral sheet around its axis aligned with Sun–Earth line in Earth’s magnetotail. We use Geotail, THEMIS and Cluster data to statistically investigate how neutral depends on sign magnitude IMF . In our dataset, we...
Abstract We investigate THEMIS satellite measurements made in a tail‐aligned constellation during time interval on 1–2 January 2009, which has previously been attributed to an of interplanetary magnetic field B y ‐driven magnetotail twisting. find evidence for that the orientation convection electric tail is twist‐mode dependent. For earthward flow and negative twist (induced < 0), found have northward E z tailward x components. During positive > directions are reversed. The component...
Abstract. Ion escape is of particular interest for studying the evolution atmosphere on geological timescales. Previously, using Cluster-CODIF data, we investigated oxygen ion outflow from plasma mantle different solar wind conditions and geomagnetic activity. We found significant correlations between parameters, activity (Kp index), O+ outflow. From these studies, suggested that ions observed in cusp have enough energy velocity to magnetosphere be lost into or distant magnetotail. Thus,...
Abstract Plasma dynamics in Earth's magnetotail is often studied using moments of the distribution function, which results losing information on kinetic properties plasma. To better understand oscillatory flows observed midtail plasma sheet, we investigate two events, one each hemisphere, transition region between central sheet and lobes 2‐D ion function from Cluster 4 spacecraft. In this case study, are a manifestation repeated flux enhancements with pitch angle changing 0° to 180° Northern...
Abstract The occurrence of tailward flows in the magnetotail plasma sheet is closely linked to dynamics earthward bursty bulk (BBFs). Tailward that are observed vicinity these BBFs (or TWABs – around BBFs) may hold unique information on its origin. In this study, we conduct a statistical survey by using data from Cluster mission. We find ∼75% and their does not depend BBF velocity magnitude. have flow convection pattern consistent with general (GTWs) they do resemble vortical‐like flows....
Signatures of hypervelocity dust impacts detected by electric field instruments are still not completely understood. We have used the instrument onboard one MMS spacecraft orbiting Earth since 2015 to study various pulses in measured simultaneously multiple antennas. This unique allows a detailed investigation registered waveforms. The preliminary results shown that solitary waves can generate similar as and easily misinterpreted when only antenna is used.