Blar i Department of Physics and Technology på tidsskrift "Journal of Geophysical Research (JGR): Space Physics"

Viser treff 1-20 av 76

    • 20 Years of Cluster Observations: The Magnetopause, 

      Håland, Stein Egil; Hasegawa, Hiroshi; Paschmann, G; Sonnerup, B. U. Ö.; Dunlop, M. W. (Journal article; Peer reviewed, 2021)
      The terrestrial magnetopause forms the boundary between the solar wind plasma with its embedded interplanetary magnetic field on one side, and the terrestrial magnetosphere, dominated by Earth's dipole field, on the other ...

    • The 3rd AGILE Terrestrial Gamma Ray Flash Catalog. Part I: Association to Lightning Sferics 

      Lindanger, Anders; Marisaldi, Martino; Maiorana, Carolina; Sarria, David; Albrechtsen, Kjetil; Østgaard, Nikolai; Galli, M.; Ursi, Alessandro; Labanti, C.; Tavani, Marco; Pittori, C.; Verrecchia, F. (Journal article; Peer reviewed, 2020)
      We present a complete and systematic search for terrestrial gamma-ray flashes (TGFs), detected by AGILE, that are associated with radio sferics detected by the World Wide Lightning Location Network (WWLLN) in the period ...

    • The 3rd AGILE Terrestrial Gamma-ray Flashes Catalog. Part II: Optimized Selection Criteria and Characteristics of the New Sample 

      Maiorana, Carolina; Marisaldi, Martino; Lindanger, Anders; Østgaard, Nikolai; Ursi, Alessandro; Sarria, David; Galli, M.; Labanti, C.; Tavani, Marco; Pittori, C.; Verrecchia, F. (Journal article; Peer reviewed, 2020)
      We present in this work the third catalog of terrestrial gamma-ray flashes (TGFs) by the AGILE mission and the new search algorithm that was developed to produce it. We firstly introduce the new selection criteria, designed ...

    • Acceleration of Oxygen Ions in Dipolarization Events: 1. CPS Distributions 

      Birn, J.; Hesse, Michael; Bingham, S.T.; Turner, D.L.; Nakamura, Rumi (Journal article; Peer reviewed, 2021)
      This paper represents the second part of an investigation of the acceleration of energetic oxygen ions from encounters with a dipolarization front (DF), based on test particle tracing in the fields of an MHD simulation. ...

    • AE, DST, and Their SuperMAG Counterparts: The Effect of Improved Spatial Resolution in Geomagnetic Indices 

      Bergin, A.; Chapman, S.C.; Gjerløv, Jesper (Journal article; Peer reviewed, 2020)
      For decades, geomagnetic indices have been used extensively to parameterize space weather events, as input to various models and as space weather specifications. The auroral electrojet (AE) index and disturbance storm time ...

    • Analysis of Thunderstorms Producing Terrestrial Gamma Ray Flashes With the Meteosat Second Generation 

      Ursi, Alessandro; Marisaldi, Martino; Dietrich, Stefano; Tavani, Marco; Tiberia, A; Porcu, Federico (Peer reviewed; Journal article, 2019)
      Up to now, only few works focused on the meteorological context leading to the production of Terrestrial Gamma ray Flashes (TGFs). In this study, we carry out, for the first time, an analysis on large scale of the ...

    • Anomalous Reconnection Layer at Earth’s Dayside Magnetopause 

      Paschmann, Goetz E.; Sonnerup, Bengt U.Ö.; Phan, Taiduc; Fuselier, Stephen Anthony; Håland, Stein Egil; Denton, Richard E.; Burch, James L.; Trattner, Karlheinz J.; Giles, Barbara L.; Gershman, Daniel J.; Cohen, Ian J.; Russell, Christopher T. (Journal article; Peer reviewed, 2021)
      Observations by the Magnetospheric Multiscale spacecraft (MMS) of an unusual layer, located between the dayside magnetosheath and the magnetosphere, alternating with encounters with the magnetosheath during an extended ...

    • Are EEP Events Important for the Tertiary Ozone Maximum? 

      Zawedde, Annet Eva; Nesse Tyssøy, Hilde; Stadsnes, Johan; Sandanger, Marit Irene J. (Peer reviewed; Journal article, 2019)
      Energetic particle precipitation (EPP) increases the production of odd hydrogen (HOX ) species in the mesosphere, which catalytically destroy ozone (O3) in sunlight. Hence, the EPP‐HOX impact on the tertiary O3 maximum ...

    • Asymmetrically Varying Guide Field During Magnetic Reconnection: Particle-In-Cell Simulations 

      Spinnangr, Susanne Flø; Tenfjord, Paul Arne Riksheim; Hesse, Michael; Norgren, Astrid Elisabet Cecilia; Kolstø, Håkon Midthun; Kwagala, Norah Kaggwa; Jørgensen, Therese; Jimenez, Judit Perez-Coll (Journal article; Peer reviewed, 2022)
      Using fully kinetic particle-in-cell modeling, we investigate how magnetic reconnection responds to a varying guide field in one of the inflow regions. We find that the reconnection rate varies significantly when the ...

    • Auroral oval morphology: Dawn-dusk asymmetry partially induced by Earth’s rotation 

      Decotte, Margot Emilie; Laundal, Karl Magnus; Hatch, Spencer Mark; Reistad, Jone Peter (Journal article; Peer reviewed, 2023)
      The auroral oval morphology has been investigated in previous studies presenting maps of average auroral precipitation. However, such distributions tend to emphasize auroral intensity rather than the actual extent of the ...

    • Characteristics of the Flank Magnetopause: MMS Results 

      Haaland, Stein; Paschmann, Götz; Oieroset, M; Phan, Tai D.; Hasegawa, Hiroshi; Fuselier, Stephen; COnstantinescu, Vlad; Eriksson, Stefan; Trattner, Karlheinz J.; Fadanelli, Sid; Tenfjord, Paul; Lavraud, Benoit; Norgren, Astrid Elisabet Cecilia; Eastwood, Jonathan P.; Hietala, Heli; Burch, J (Journal article; Peer reviewed, 2020)
      We have used a large number of magnetopause crossings by the Magnetospheric Multiscale (MMS) mission to investigate macroscopic properties of this current sheet, with emphasis on the flanks of the magnetopause. Macroscopic ...

    • Characteristics of the Flank Magnetopause: THEMIS Observations 

      Haaland, Stein; Runov, Andrei; Artemyev, Anton; Angelopoulos, Vassillis (Peer reviewed; Journal article, 2019-05-30)
      The terrestrial magnetopause is the boundary that shields the Earth's magnetosphere on one side from the shocked solar wind and its embedded interplanetary magnetic field on the other side. In this paper, we show observations ...

    • Comparison of Quality Measures for Walén Relation 

      Paschmann, G; Sonnerup, B. U. Ö.; Haaland, Stein; Phan, T.D.; Denton, Richard E (Journal article; Peer reviewed, 2020)
      The standard method for identifying magnetohydrodynamic rotational discontinuities in spacecraft data has been to examine how well the Walén relation is satisfied. In this paper, we apply two different versions of the Walén ...

    • Constraints on Recoil Leader Properties Estimated from X-ray Emissions in Aircraft-Triggered Discharges 

      Skeie, Chris Alexander Kallevik; Østgaard, Nikolai; Lehtinen, Nikolai; Sarria, David; Kochkin, Pavlo; de Boer, Boer; Bardet, M.; Allasia, C.; Flourens, F. (Journal article; Peer reviewed, 2020)
      During Airbus aircraft campaigns flying into thunderstorms in 2014–2016, X-rays were observed during two stages of aircraft-triggered lightning: nanosecond pulses of X-rays associated with negative leader steps and bursts ...

    • Convection in the Magnetosphere-Ionosphere System: A Multimission Survey of Its Response to IMF By Reversals 

      Case, Nathan A; Grocott, Adrian; Fear, Robert C.; Haaland, Stein; Lane, J. H. (Journal article; Peer reviewed, 2020)
      Past studies have demonstrated that the interplanetary magnetic field (IMF) By component introduces asymmetries in the magnetosphere‐ionosphere (M‐I) system, though the exact timings involved are still unclear with two ...

    • Curlometer Technique and Applications 

      Dunlop, M; Dong, X.C; Wang, T. C.; Eastwood, JP; Robert, P; Håland, Stein Egil; Yang, Y.; Escoubet, C. P.; Rong, ZJ; Shen, C; Fu, H.; De Keyser, Johan (Journal article; Peer reviewed, 2021)
      We review the range of applications and use of the curlometer, initially developed to analyze Cluster multi-spacecraft magnetic field data; but more recently adapted to other arrays of spacecraft flying in formation, such ...

    • Cutoff Latitudes of Solar Proton Events Measured by GPS Satellites 

      van Hazendonk, Charlotte Maartje; Heino, Erkka Petteri; Jiggens, Piers T.A.; Taylor, Matthew G.G.T.; Partamies, Noora; Mulders, Hjalmar C. J. (Journal article; Peer reviewed, 2022)
      Solar energetic particles (SEPs), one of the main causes of particle radiation in interplanetary space, can disrupt radio communication, induce spacecraft failures and change the heating and cooling rates in the atmosphere ...

    • Determining Latitudinal Extent of Energetic Electron Precipitation Using MEPED On-Board NOAA/POES 

      Babu, Eldho Midhun; Tyssøy, Hilde Nesse; Smith-Johnsen, Christine; Maliniemi, Ville Aleksi; Salice, Josephine Alessandra; Millan, R.M.; Richardson, I.G. (Journal article; Peer reviewed, 2022)
      Energetic Electron Precipitation (EEP) from the plasma sheet and the radiation belts ionizes the polar lower thermosphere and mesosphere. EEP increases the production of NOx and HOx, which will catalytically destroy ozone, ...

    • Dual-Lobe Reconnection and Horse-Collar Auroras 

      Milan, Stephen Eric; Carter, Jennifer Alyson; Bower, G.E.; Imber, S.M.; Paxton, Larry J.; Anderson, Brian J.; Hairston, Marc; Hubert, Benoit (Journal article; Peer reviewed, 2020)
      We propose a mechanism for the formation of the horse-collar auroral configuration during periods of strongly northward interplanetary magnetic field (IMF), invoking the action of dual-lobe reconnection (DLR). Auroral ...

    • Effect of Energetic Electron Precipitation on the Northern Polar Vortex: Explaining the QBO Modulation via Control of Meridional Circulation 

      Salminen, A; Asikainen, T.; Maliniemi, Ville Aleksi; Mursula, K. (Peer reviewed; Journal article, 2019)
      Energetic electron precipitation (EEP) affects the high‐latitude middle atmosphere by producing NOX compounds that destroy ozone. Earlier studies have shown that in the wintertime polar stratosphere, increased EEP enhances ...