SH035-08
Current sheet structure and associated small-scale flux ropes in the heliospheric magnetic field observed by Solar Orbiter
Monday, 14 December 2020: 04:28
Virtual
Jonathan P Eastwood1, Julia E Stawarz2, Sadie Robertson1, Lingling Zhao3, Gary Paul Zank4, Tai Phan5, Michael A Shay6, Yuri Khotyaintsev7, Heli Hietala8, Samuel Bennett9, Benoit Lavraud10, Robert F Wimmer-Schweingruber11, Lars Berger12, Javier Rodriguez-Pacheco13, Milan Maksimovic14, Stuart Bale15, Thomas Chust16, Matthieu Kretzschmar17, Dirk Plettemeier18, Jan Soucek19, Manfred Steller20, Stepan Stverak21, Antonio Vecchio22, Andris Vaivads23, Eric Lorfevre24, Vladimir Krasnoselskikh25, Pavel M. Travnicek26, Christopher John Owen27, Roberto Bruno28, Philippe Louarn29, Stefano A Livi30, Virginia Angelini31, Vincent Evans31, Helen O'Brien2 and Timothy Simon Horbury2, (1)Imperial College London, Physics, London, SW7, United Kingdom, (2)Imperial College London, Department of Physics, London, SW7, United Kingdom, (3)Center for Space Plasma and Aeronomic Research, Huntsville, AL, United States, (4)Univ of Alabama, Huntsville, Huntsville, AL, United States, (5)Univ California, Berkeley, CA, United States, (6)University of Delaware, Newark, DE, United States, (7)IRF Swedish Institute of Space Physics, Uppsala, Sweden, (8)University of Turku, Turku, Finland, (9)Imperial College London, London, United Kingdom, (10)IRAP/CNRS, Toulouse, France, (11)University of Kiel, Institute for Experimental and Applied Physics, Kiel, Germany, (12)Institute for Experimental and Applied Physics (IEAP), Christian-Albrechts-University of Kiel, Kiel, Germany, (13)Universidad de Alcalá, Space Research Group, Alcalá de Henares, Spain, (14)LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, Meudon, France, (15)University of California, Berkeley, Berkeley, CA, United States, (16)Laboratoire de Physique des Plasmas (UMR7648), CNRS/Ecole Polytechnique/UPMC/Univ. Paris Sud/Obs. de Paris, Paris, France, (17)CNRS and University of Orléans, LPC2E, Orléans, France, (18)Dresden University of Technology, Dresden, Germany, (19)Inst. of Atmospheric Physics, Praha 4, Czech Republic, (20)Space Research Institute, Austrian Academy of Sciences, Graz, Austria, (21)Astronomical Institute AS CR, Prague, Czech Republic, (22)Paris Observatory Meudon, Meudon, France, (23)School of Electrical Engineering and Computer Science, Royal Institute of Technology, Department of Space and Plasma Physics, Stockholm, Sweden, (24)CNES French National Center for Space Studies, Toulouse Cedex 09, France, (25)LPC2E, CNRS and University of Orléans, Orléans, France, (26)University of California Berkeley, Space Sciences Laboratory, Berkeley, CA, United States, (27)University College London, Mullard Space Science Laboratory, Dorking, United Kingdom, (28)INAF-IFSI, Rome, Italy, (29)IRAP, CNRS, Toulouse, France, (30)SwRI, San Antonio, TX, United States, (31)Imperial College London, Department of Physics, London, United Kingdom
Abstract:
A notable feature of current sheets in the magnetosphere of Earth and other planets is the formation of flux ropes, helical magnetic field structures which are thought to play a key role in the dynamics of the current sheet and in particle acceleration models. Flux ropes are commonly produced by magnetic reconnection, and so provide insight into the time-dependent nature of the reconnection process. Reconnection is also an important target for studies of solar wind physics as it controls the topology of the heliospheric magnetic field and may also enable particle heating and acceleration. In contrast to the Earth’s magnetosphere, current sheets in the solar wind extend to very large scales, reconnection is typically large scale and relatively steady-state, and observations of flux ropes contained within solar wind current sheets are very rare, even though they are a potentially important component of many particle acceleration models. The general properties of such flux ropes are therefore poorly understood, including their prevalence and size distribution.
Solar Orbiter, launched in February 2020, provides a new opportunity to study this problem. Here we present new observations of current sheets and flux ropes in the heliospheric magnetic field, and focus in particular on one event where the signature of a small-scale flux rope was observed confined within a solar wind current sheet. We further examine the properties of the current sheet, the structure of the flux rope, and the nature of the enhanced magnetic fluctuations throughout the current sheet crossing. These results provide new insight into the relationship between solar wind current sheets and flux rope formation, extending the hierarchy of scales over which flux ropes are found to exist in the solar wind.
