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THE OBJECTIVE OF THIS PROPOSAL IS TO UNDERSTAND THE DYNAMICS OF VELOCITY SHEAR IN THE EARTH S MAGNETOSPHERE AND PLASMA TRANSPORT AND HEATING ASSOCIATED WITH VORTICITY AND TURBULENCE INDUCED BY VELOCITY SHEAR. VELOCITY SHEAR THAT TRIGGERS THE ONSET OF THE KELVIN-HELMHOLTZ INSTABILITY (KHI) AND GENERATES FLOW VORTICITY IS A UBIQUITOUS PHENOMENON IN THE GEOSPACE ENVIRONMENT E.G. ON THE MAGNETOPAUSE ON THE INNER EDGE OF THE LOW-LATITUDE BOUNDARY LAYER (LLBL) AND IN THE CENTRAL PLASMA SHEET. FLOW VORTICES ARE AN IMPORTANT ELEMENT OF TURBULENCE MEDIATING THE PARTICLE AND HEAT TRANSPORT AND THE ENERGY CONVERSION AT EARTH ENVIRONMENTS. KELVIN-HELMHOLTZ VORTICES (KHVS) IN THE OUTER MAGNETOSPHERE AND NEAR THE MAGNETIC RECONNECTION AND BBF/DF REGIONS IN THE CENTRAL PLASMA SHEET MAY CHANGE LARGE-SCALE MAGNETOSPHERIC FLOW PATTERNS AND THE PROPERTIES OF MAGNETOSPHERIC REGIONS SUCH AS PLASMA DENSITY AND TEMPERATURE VIA DIFFUSIVE TRANSPORT AND TURBULENT DISSIPATION. YET OUR UNDERSTANDING OF THE INFLUENCE AND IMPACTS OF SHEAR-DRIVEN VORTICES ON THE SOLAR WIND-MAGNETOSPHERE COUPLING AND ON THE MAGNETOSPHERE-IONOSPHERE INTERACTION IS AT A PRIMITIVE STAGE. WE PURSUE TO ADDRESS THE FOLLOWING QUESTIONS: (Q1) HOW AND HOW SIGNIFICANTLY DO OUTER-BOUNDARY AND CENTRAL-MAGNETOTAIL VORTICES AFFECT SOLAR WIND TRANSPORT AND GENERAL FLOW PATTERNS IN THE MAGNETOSPHERE SYSTEM? (Q2) HOW AND HOW EFFECTIVELY DOES VELOCITY SHEAR DRIVEN TURBULENCE IN THE OUTER BOUNDARY AND THE CENTRAL MAGNETOTAIL LEAD TO PLASMA HEATING? (Q3) WHAT ARE THE ROLES OF ION AND ELECTRON-SCALE DYNAMICS IN VELOCITY-SHEAR-DRIVEN TRANSPORT AND HEATING? (Q4) HOW DO TURBULENCE TRANSPORT AND HEATING INDUCED BY FLOW VORTICES DIFFER FOR SOUTHWARD VS. NORTHWARD IMF CONDITIONS AND WITH/WITHOUT HIGH-SPEED SOLAR-WIND STREAMS?

$210,685FY2020National Aeronautics and Space AdministrationNASA

Southwest Research Institute, San Antonio TX

Investigators

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