• 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. ...
    • AME: A Cross-Scale Constellation of CubeSats to Explore Magnetic Reconnection in the Solar–Terrestrial Relation 

      Dai, Lei; Wang, Chi; Cai, Zhiming; Gonzalez, Walter D.; Hesse, Michael; Escoubet, Philippe; Phan, Tai D.; Vasyliunas, Vytenis; Lu, Quanming; Li, Lei; Kong, Linggao; Dunlop, Malcolm W.; Nakamura, Rumi; He, Jianshen; Fu, Huishan; Zhou, M.; Huang, Shiyong; Wang, Rongsheng; Khotyaintsev, Yuri V.; Graham, D. B.; Retinò, Alessandro; Zelenyi, Lev; Grigorenko, Elena E.; Runov, Andrei; Angelopoulos, Vassilis; Kepko, Larry; Hwang, Kyoung-Joo; Zhang, Yongcun (Journal article; Peer reviewed, 2020)
      A major subset of solar–terrestrial relations, responsible, in particular, for the driver of space weather phenomena, is the interaction between the Earth's magnetosphere and the solar wind. As one of the most important ...
    • The asymmetric geospace as displayed during the geomagnetic storm on 17 August 2001 

      Østgaard, Nikolai; Reistad, Jone Peter; Tenfjord, Paul; Laundal, Karl Magnus; Rexer, Theresa; Haaland, Stein; Snekvik, Kristian; Hesse, Michael; Milan, Stephen Eric; Ohma, Anders (Peer reviewed; Journal article, 2018-11-29)
      Previous studies have shown that conjugate auroral features are displaced in the two hemispheres when the interplanetary magnetic field (IMF) has a transverse (Y) component. It has also been shown that a BY component is ...
    • Collisionless Magnetic Reconnection in an Asymmetric Oxygen Density Configuration 

      Kolstø, Håkon Midthun; Hesse, Michael; Norgren, Astrid Elisabet Cecilia; Tenfjord, Paul; Spinnangr, Susanne Flø; Kwagala, Norah Kaggwa (Journal article; Peer reviewed, 2020)
      Combined with the magnetic field, the distribution of charged particles in the inflow region is expected to control the rate of magnetic reconnection. This paper investigates how the reconnection process is altered by a ...
    • Effects of the guide field on electron distribution functions in the diffusion region of asymmetric reconnection 

      Bessho, Naoki; Chen, Lijen; Wang, Shan; Hesse, Michael (Peer reviewed; Journal article, 2019)
      Crescent electron distribution functions in the electron diffusion region in asymmetric reconnection with a guide field (strength less than 50% of the upstream magnetic field) are investigated by theory and fully kinetic ...
    • 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 ...
    • Electron inflow velocities and reconnection rates at earth's magnetopause and magnetosheath 

      Burch, James L.; Webster, James M.; Hesse, Michael; Genestreti, Kevin J.; Denton, Richard E.; Phan, Tai D.; Hasegawa, Hiroshi; Cassak, Paul A.; Torbert, Roy B.; Giles, Barbara L.; Gershman, Daniel J.; Ergun, Robert E.; Russell, Christopher T.; Strangeway, Robert J.; Le Contel, Olivier; Pritchard, Kris R.; Marshall, Andrew T.; Hwang, Kyoung-Joo; Dokgo, Kyunghwan; Fuselier, Stephen A.; Chen, Li-Jen; Wang, Shan; Swisdak, Marc; Drake, James F.; Argall, Matthew R.; Trattner, Karlheinz J.; Yamada, Masaaki; Paschmann, Götz (Journal article; Peer reviewed, 2020)
      Electron inflow and outflow velocities during magnetic reconnection at and near the dayside magnetopause are measured using satellites from NASA's Magnetospheric Multiscale (MMS) mission. A case study is examined in detail, ...
    • Estimating the Rate of Cessation of Magnetospheric Activity in AMPERE Field‐Aligned Currents 

      Moretto, T; Hesse, Michael; Vennerstrøm, Susanne; Tenfjord, Paul (Peer reviewed; Journal article, 2018-12)
      The decay of magnetospheric activity when driving is turned off (to a minimum) was measured in total field‐aligned current estimates from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) ...
    • 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 ...
    • The Impact of Oxygen on the Reconnection Rate 

      Tenfjord, Paul; Hesse, Michael; Norgren, Astrid Elisabet Cecilia; Spinnangr, Susanne Flø; Kolstø, Håkon Midthun (Peer reviewed; Journal article, 2019-05-29)
      We investigate the role of a background oxygen population in magnetic reconnection, using particle‐in‐cell simulations. We run several simulations, with different initial oxygen temperatures and densities, to understand ...
    • 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 ...
    • Ion Behaviors in the Reconnection Diffusion Region of a Corrugated Magnetotail Current Sheet 

      Wang, Shan; Chen, Li-Jen; Bessho, Naoki; Hesse, Michael; Giles, Barbara L; Moore, Thomas E (Journal article; Peer reviewed, 2019)
      The current sheet structure and ion behaviors in a magnetotail reconnection diffusion region are investigated. The multispacecraft analysis suggests a corrugated current sheet structure, interpreted as due to a flapping ...
    • Lower-Hybrid Drift Waves Driving Electron Nongyrotropic Heating and Vortical Flows in a Magnetic Reconnection Layer 

      Chen, Li-Jen; Wang, Shan; Le Contel, Olivier; Rager, A.; Hesse, Michael; Drake, J. F.; Dorelli, J.; Ng, J.; Bessho, Naoki; Graham, D. B.; Wilson, Lynn B.; Moore, T. E.; Giles, B. L.; Paterson, W.; Lavraud, B.; Genestreti, K.; Nakamura, Rumi; Khotyaintsev, Yuri V.; Ergun, R.E.; Torbert, Roy B.; Burch, J. L.; Pollock, C.; Russell, Christopher T.; Lindqvist, Per-Arne; Avanov, Levon (Journal article; Peer reviewed, 2020)
      We report measurements of lower-hybrid drift waves driving electron heating and vortical flows in an electron-scale reconnection layer under a guide field. Electrons accelerated by the electrostatic potential of the waves ...
    • Magnetic Reconnection in a Quasi-Parallel Shock: Two-Dimensional Local Particle-in-Cell Simulation 

      Bessho, Naoki; Chen, Lijen; Wang, Shan; Hesse, Michael; Wilson, Lynn B. (Peer reviewed; Journal article, 2019)
      Magnetic reconnection in a quasi‐parallel bow shock is investigated with two‐dimensional local particle‐in‐cell simulations. In the shock transition and downstream regions, large amplitude magnetic fluctuations exist, and ...
    • Magnetic Reconnection in Three Dimensions: Modeling and Analysis of Electromagnetic Drift Waves in the Adjacent Current Sheet 

      Ergun, Robert E; Hoilijoki, Sanni; Ahmadi, N.; Schwartz, S.J.; Wilder, F.D.; Drake, James F.; Hesse, Michael; Shay, Michael A.; Ji, H.; Yamada, M; Graham, Daniel B.; Cassak, P.A.; Swisdak, M; Burch, J. L.; Torbert, R.B.; Holmes, JC; Stawarz, JE; Goodrich, Katherine A; Eriksson, S.; Strangeway, Robert J.; LeContel, O (Journal article; Peer reviewed, 2019)
      We present a model of electromagnetic drift waves in the current sheet adjacent to magnetic reconnection at the subsolar magnetopause. These drift waves are potentially important in governing 3‐D structure of subsolar ...
    • Magnetospheric Multiscale Observations of an Expanding Oxygen Wave in Magnetic Reconnection 

      Kolstø, Håkon Midthun; Norgren, Astrid Elisabet Cecilia; Hesse, Michael; Chen, Li-Jen; Tenfjord, Paul; Spinnangr, Susanne Flø; Kwagala, Norah Kaggwa (Journal article; Peer reviewed, 2021)
      Heavier plasma species such as oxygen ions can have a large impact on the magnetic reconnection process. It has been hypothesized that the acceleration of demagnetized oxygen ions by the Hall electric field will lead to ...
    • Mass‐loading the Earth's dayside magnetopause boundary layer and its effect on magnetic reconnection 

      Fuselier, Stephen; Trattner, K.J.; Petrinec, Steve M.; Denton, Mike; Toledo, Sergio P.A.; Andrè, M.; Aunai, N; Chappell, Charles Richard; Glocer, Alex; Haaland, Stein; Hesse, Michael; Kistler, Lynn M.; Li, Wenya; Moore, T. E.; Graham, Daniel B.; Alm, Love; Tenfjord, Paul; Dargen, Jeremy; Vines, Sarah; Nykyri, K.; Burch, James L; Strangeway, Robert J. (Peer reviewed; Journal article, 2019)
      When the interplanetary magnetic field is northward for a period of time, O+ from the high‐latitude ionosphere escapes along reconnected magnetic field lines into the dayside magnetopause boundary layer. Dual‐lobe reconnection ...
    • The Micro-Macro Coupling of Mass-Loading in Symmetric Magnetic Reconnection With Cold Ions 

      Spinnangr, Susanne Flø; Hesse, Michael; Tenfjord, Paul Arne Riksheim; Norgren, Astrid Elisabet Cecilia; Kolstø, Håkon Midthun; Kwagala, Norah Kaggwa; Jørgensen, Therese Moretto (Journal article; Peer reviewed, 2021)
      We investigate how magnetic reconnection is influenced by an inflow of a dense cold ion population. We compare two 2.5D Particle-In-Cell simulations, one containing the cold population and one without. We find that the ...
    • Millisecond observations of nonlinear wave–electron interaction in electron phase space holes 

      Norgren, Astrid Elisabet Cecilia; Graham, Daniel B.; Argall, Matthew; Steinvall, Konrad; Hesse, Michael; Khotyaintsev, Yuri V.; Vaivads, Andris; Tenfjord, Paul Arne Riksheim; Gershman, Daniel J; Lindqvist, Per-Arne; Burch, James L; Plaschke, Ferdinand (Journal article; Peer reviewed, 2022)
      Electron phase space holes (EHs) associated with electron trapping are commonly observed as bipolar electric field signatures in both space and laboratory plasma. Until recently, it has not been possible to resolve EHs in ...
    • A new Look at the Electron Diffusion Region in Asymmetric Magnetic Reconnection 

      Hesse, Michael; Norgren, Astrid Elisabet Cecilia; Tenfjord, Paul; James L., Burch; Liu, Yi‐Hsin; Bessho, Naoki; Wang, Shan; Kolstø, Håkon Midthun; Spinnangr, Susanne Flø; Ergun, Robert E; Moretto, Therese; Kwagala, Norah Kaggwa (Journal article; Peer reviewed, 2021)
      A new look at the structure of the electron diffusion region in collision less magnetic reconnection is presented. The research is based on a particle-in-cell simulation of asymmetric magnetic reconnection, which includes ...