• 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 ...
    • 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 ...
    • 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 ...
    • 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; 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 ...
    • 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 ...
    • Electron Acceleration and Thermalization at Magnetotail Separatrices 

      Norgren, Astrid Elisabet Cecilia; Hesse, Michael; Graham, Daniel B.; Khotyaintsev, Yuri V.; Tenfjord, Paul; Vaivads, Andris; Steinvall, Konrad; Xu, Yin; Gershman, Daniel J; Lindqvist, Per-Arne; Plaschke, Ferdinand; Burch, James L (Journal article; Peer reviewed, 2020)
      In this study we use the Magnetospheric Multiscale mission to investigate the electron acceleration and thermalization occurring along the magnetic reconnection separatrices in the magnetotail. We find that initially cold ...
    • First 10 Months of TGF Observations by ASIM 

      Østgaard, Nikolai; Neubert, Torsten; Reglero, Victor; Ullaland, Kjetil; Yang, Shiming; Genov, Georgi; Marisaldi, Martino; Mezentsev, Andrey; Kochkin, Pavlo; Lehtinen, Nikolai; Sarria, David; Qureshi, Bilal Hasan; Solberg, Arne Olav; Maiorana, Carolina; Albrechtsen, Kjetil; Budtz-Jørgensen, Carl; Kuvvetli, Irfan; Christiansen, Freddy; Chanrion, Olivier; Heumesser, Matthias; Navarro-Gonzalez, Javier; Connell, Paul H.; Eyles, Christopher J; Christian, Hugh J.; Al-Nussirat, Samer (Peer reviewed; Journal article, 2019)
      The Atmosphere‐Space Interactions Monitor (ASIM) was launched to the International Space Station on 2 April 2018. The ASIM payload consists of two main instruments, the Modular X‐ray and Gamma‐ray Sensor (MXGS) for imaging ...
    • Gamma Ray Glow Observations at 20-km Altitude 

      Østgaard, Nikolai; Christian, Hugh J.; Grove, J. Eric; Sarria, David; Mezentsev, Andrey; Kochkin, Pavlo; Lehtinen, Nikolai; Quick, Mason; Al-Nussirat, Samer; Wulf, Eric; Genov, Georgi; Ullaland, Kjetil; Marisaldi, Martino; Yang, Shiming; Blakeslee, Richard J. (Peer reviewed; Journal article, 2019)
      In the spring of 2017 an ER‐2 aircraft campaign was undertaken over continental United States to observe energetic radiation from thunderstorms and lightning. The payload consisted of a suite of instruments designed to ...
    • A Generalized Method for Calculating Atmospheric Ionization by Energetic Electron Precipitation 

      Xu, Wei; Marshall, Robert A.; Tyssøy, Hilde Nesse; Fang, Xiaohua (Journal article; Peer reviewed, 2020)
      Accurate specification of ionization production by energetic electron precipitation is critical for atmospheric chemistry models to assess the resultant atmospheric effects. Recent model-observation comparison studies have ...
    • High‐density magnetospheric He+ at the dayside magnetopause and its effect on magnetic reconnection 

      Fuselier, Stephen A.; Haaland, Stein; Tenfjord, Paul; Paschmann, G; Toledo-Redondo, S; Malaspina, D; Kim, M.J.; Trattner, K.J.; Petrinec, S. M.; Giles, B. L.; Goldstein, J; Burch, J. L.; Strangeway, R. J. (Journal article; Peer reviewed, 2021)
      Observations from the Magnetospheric Multiscale (MMS) mission are used to quantify the maximum effect of magnetospheric H+ and He+ on dayside magnetopause reconnection. A data base of current-sheet crossings from the first ...
    • High‐density O+ in Earth's outer magnetosphere and its effect on dayside magnetopause magnetic reconnection 

      Fuselier, SA; Mukherjee, J; Denton, MH; Petrinec, SM; Trattner, K.J.; Toledo-Redondo, S; Andre, M; Aunai, N; Chappell, Charles Richard; Glocer, Alex; Haaland, S.; Hesse, Michael; Kistler, LM; Lavraud, B; Li, WY; Moore, T. E.; Graham, D; Tenfjord, Paul; Dargent, J.; Vines, Sarah K.; Strangeway, Robert J.; Burch, J. L. (Journal article; Peer reviewed, 2019)
      The warm plasma cloak is a source of magnetospheric plasma that contain significant O+. When the O+ density in the magnetosphere near the magnetopause is >0.2 cm‐3 and the H+ density is <1.5 cm‐3, then O+ dominates the ...
    • Inferring source properties of monoenergetic electron precipitation from kappa and Maxwellian moment‐voltage relationships 

      Hatch, Spencer Mark; LaBelle, James; Chaston, C. C. (Peer reviewed; Journal article, 2019)
    • Interaction of Cold Streaming Protons with the Reconnection Process 

      Tenfjord, Paul; Hesse, Michael; Norgren, Astrid Elisabet Cecilia; Spinnangr, Susanne Flø; Kolstø, Håkon Midthun; Kwagala, Norah Kaggwa (Journal article; Peer reviewed, 2020)
      We employ a 2.5D particle-in-cell simulation to study a scenario where the reconnection process captures cold streaming protons. As soon as the tailward streaming protons become involved, they contribute to the overall ...