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@Article{LopezGonz:2017:MaBaSo,
               author = "Lopez, Ramon E. and Gonzalez Alarcon, Walter Dem{\'e}trio",
          affiliation = "{University of Texas at Arlington} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "Magnetospheric balance of solar wind dynamic pressure",
              journal = "Geophysical Research Letters",
                 year = "2017",
               volume = "44",
               number = "7",
                pages = "2991--2999",
                month = "Apr.",
             keywords = "magnetopause, bow shock, currents.",
             abstract = "The magnetopause is the boundary established by pressure balance 
                         between the solar wind flow in the magnetosheath and the 
                         magnetosphere. Generally, this pressure balance is represented to 
                         be between the solar wind, the dynamic pressure, and the magnetic 
                         pressure of Earth's dipole field. The plasma actually in contact 
                         with the magnetosphere is the slowed, compressed, and heated solar 
                         wind downstream of the shock. The force exerted on the 
                         magnetosheath plasma is the JxB force produced by the 
                         Chapman-Ferraro current that flows on the magnetopause. Under 
                         typical solar wind conditions of relatively high magnetosonic Mach 
                         number flow (>6), this simple picture is a reasonable description 
                         of the situation. However, under conditions of low solar wind 
                         magnetosonic Mach number flow (similar to 2) the force on the 
                         solar wind plasma is not exerted at the magnetopause and must be 
                         exerted at the bow shock by currents that connect to the Region 1 
                         currents. In this paper we present observations from two 
                         magnetopause crossings observed by the Time History of Events and 
                         Macroscale Interactions during Substorms spacecraft to compare and 
                         contrast the force balance with the solar wind for two situations 
                         with very different solar wind magnetosonic Mach numbers. Plain 
                         Language Summary When the solar wind hits Earth's magnetic field, 
                         the magnetic field pushes back on the solar wind. Typically, this 
                         force is exerted at the boundary between Earth's magnetic field 
                         and the solar wind. However, when the supersonic solar wind has a 
                         low Mach number (about 2, as opposed to the typical value of >6), 
                         the place where the force is exerted on the solar wind is at the 
                         bow shock wave in front of Earth. This force is produced by an 
                         electric current that flows on the bow shock and which connects to 
                         currents that flow directly into Earth's ionosphere in the polar 
                         regions. This paper presents spacecraft observations documenting 
                         this unusual situation.",
                  doi = "10.1002/2017GL072817",
                  url = "http://dx.doi.org/10.1002/2017GL072817",
                 issn = "0094-8276",
             language = "en",
           targetfile = "lopez_magnetospheric.pdf",
        urlaccessdate = "29 nov. 2020"
}


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