• 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 ...
    • Atmospheric Drag, Occultation 'N' Ionospheric Scintillation (ADONIS) mission proposal: Alpbach Summer School 2013 team orange 

      Hettrich, Sebastian; Kempf, Yann; Perakis, Nikolaos; Górski, Jędrzej; Edl, Martina; Urbář, Jaroslav; Dósa, Melinda; Gini, Francesco; Roberts, Owen W.; Schindler, Stefan; Schemmer, Maximilian; Steenari, David; Joldžić, Nina; Ødegaard, Linn-Kristine Glesnes; Sarria, David; Volwerk, Martin; Praks, Jaan (Peer reviewed; Journal article, 2015)
      The Atmospheric Drag, Occultation ‘N’ Ionospheric Scintillation mission (ADONIS) studies the dynamics of the terrestrial thermosphere and ionosphere in dependency of solar events over a full solar cycle in Low Earth Orbit ...
    • 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 ...
    • 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 ...
    • In‐Flight Observation of Positron Annihilation by ILDAS 

      Kochkin, Pavlo; Sarria, David; Skeie, Chris Alexander; Van Deursen, Alexander P.J.; de Boer, A; Bardet, Michiel; Allasia, Cedric; Flourens, Franck; Østgaard, Nikolai (Peer reviewed; Journal article, 2018-08)
      We report a 511‐keV photon flux enhancement that was observed inside a thundercloud and is a result of positron annihilation. The observation was made with the In‐flight Lightning Damage Assessment System (ILDAS) on board ...
    • On the High‐Energy Spectral Component and Fine Time Structure of Terrestrial Gamma Ray Flashes 

      Marisaldi, Martino; Galli, M.; Labanti, C.; Østgaard, Nikolai; Sarria, David; Cummer, S. A.; Lyu, F.; Lindanger, Anders; Campana, R.; Ursi, A.; Tavana, M; Fuschino, F.; Argan, A.; Trois, A.; Pittori, C.; Verrecchia, F (Journal article; Peer reviewed, 2019)
      Terrestrial gamma ray flashes (TGFs) are very short bursts of gamma radiation associated to thunderstorm activity and are the manifestation of the highest‐energy natural particle acceleration phenomena occurring on Earth. ...