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PROMINENCES (OR FILAMENTS) ARE ELONGATED COLD AND DENSE PLASMA STRUCTURES THAT ARE OBSERVED IN THE SOLAR CORONA FOR UP TO SEVERAL MONTHS BEFORE THEY OFTEN ERUPT AS PART OF A CORONAL MASS EJECTION (CME). IT IS NOW WELL ESTABLISHED THAT PROMINENCES ARE SUSPENDED BY SHEARED/TWISTED MAGNETIC FIELDS WHICH ALSO THERMALLY ISOLATE THE PROMINENCE PLASMA FROM THE 100 TIMES HOTTER AND LESS DENSE CORONA. HOWEVER THE DETAILS OF PROMINENCE FORMATION AND OF THE EVOLUTION OF PROMINENCE PLASMA IN CMES AND IN INTERPLANETARY SPACE ARE NOT YET WELL UNDERSTOOD. THE PRESENTLY MOST FAVORED SCENARIO FOR PROMINENCE FORMATION IS THE "THERMAL NON-EQUILIBRIUM" (TNE) MECHANISM WHICH IS BASED ON CORONAL PLASMA CONDENSATION RESULTING FROM FOOT-POINT HEATING AND PLASMA EVAPORATION. THIS MECHANISM HAS BEEN MODELED EXTENSIVELY FOR ONE-DIMENSIONAL (1D) MAGNETIC CONFIGURATIONS. TIME-DEPENDENT FULLY 3D MAGNETOHYDRODYNAMIC (MHD) SIMULATIONS WHICH ARE REQUIRED FOR VALIDATION AND FOR A DEEPER UNDERSTANDING OF THE UNDERLYING PHYSICS EXIST ONLY SINCE A FEW YEARS. VERY RECENTLY THE FIRST SIMULATION OF THE ERUPTION OF A PROMINENCE PRODUCED BY EVAPORATION AND CONDENSATION WAS PRESENTED. HOWEVER ONLY IDEALIZED FLUXROPE CONFIGURATIONS AND AD HOC HEATING FUNCTIONS HAVE BEEN CONSIDERED SO FAR AND THE INTERPLANETARY PROPAGATION OF SELF-CONSISTENTLY FORMED PROMINENCE PLASMA HAS NOT YET BEEN MODELED. MORE SOPHISTICATED SIMULATIONS THAT INCLUDE REALISTIC MAGNETIC CONFIGURATIONS AND PHYSIC-BASED HEATING MODELS ARE THEREFORE NEEDED. WE PROPOSE TO USE OUR THERMODYNAMIC MHD CODE MAS TO SYSTEMATICALLY MODEL AND INVESTIGATE THE FORMATION ERUPTION AND INTERPLANETARY PROPAGATION OF PROMINENCES. SIGNIFICANTLY EXTENDING EXISTING SIMULATIONS WE WILL CONSIDER DIFFERENT IDEALIZED FLUXROPE CONFIGURATIONS AND USE THE PHYSICS-BASED WAVE-TURBULENCE-DRIVEN (WTD) FORMALISM FOR HEATING THE CORONA. EMPLOYING OUR EXTENSIVE EXPERIENCE IN SIMULATING SOLAR ERUPTIONS WE WILL ALSO SIMULATE FOR THE FIRST TIME THE FORMATION ERUPTION AND INTERPLANETARY PROPAGATION OF OBSERVED PROMINENCES. NASA SPACECRAFT OBSERVATIONS WILL BE USED TO CONSTRUCT AND CONSTRAIN THESE CONFIGURATIONS AND FOR A DIRECT COMPARISON WITH THE SIMULATION RESULTS. IN TURN WE WILL USE OUR RESULTS TO INTERPRET SUCH OBSERVATIONS AND IN SITU MEASUREMENTS. OUR INNOVATIVE APPROACH WILL ALLOW US TO ADDRESS IMPORTANT SCIENTIFIC QUESTIONS SUCH AS: (1) HOW DO THE GEOMETRY AND THE ELECTRIC CURRENT DISTRIBUTION OF A FLUX ROPE EFFECT THE FORMATION AND PERSISTENCE OF PROMINENCE PLASMA? (2) CAN WTD HEATING SELF-CONSISTENTLY LEAD TO PROMINENCE FORMATION OR IS LOCALIZED FOOT-POINT HEATING STILL REQUIRED? (3) WHAT DETERMINES HOW MUCH PROMINENCE PLASMA IS EJECTED FROM THE SUN DURING AN ERUPTION AND TO WHAT EXTENT IS IT HEATED BY FLARE RECONNECTION? (4) HOW EXACTLY IS PROMINENCE PLASMA DISTRIBUTED IN CMES? (5) HOW DOES PROMINENCE PLASMA EVOLVE DURING ITS PROPAGATION IN THE OUTER CORONA AND INTERPLANETARY SPACE?NASA'S H-SR PROGRAM ENCOURAGES INVESTIGATIONS THAT COMBINE NUMERICAL MODELING WITH DATA ANALYSIS/INTERPRETATION AND ADDRESS (AT LEAST) ONE OF THE FOUR HELIOSPHERIC DECADAL SURVEY GOALS. THE WORK PROPOSED HERE WILL ACCOMPLISH THAT BY PERFORMING STATE-OF-THE ART MHD SIMULATIONS AND BY USING AND INTERPRETING OBSERVATIONS FROM NASA SPACECRAFT. IT ADDRESSES THE SURVEY GOALS "TO DETERMINE THE ORIGINS OF THE SUN S ACTIVITY AND PREDICT THE VARIATIONS IN THE SPACE ENVIRONMENT" AND "TO DISCOVER AND CHARACTERIZE FUNDAMENTAL PROCESSES THAT OCCUR BOTH WITHIN THE HELIOSPHERE AND THROUGHOUT THE UNIVERSE".

$707,355FY2020National Aeronautics and Space AdministrationNASA

Predictive Science Incorporated, San Diego CA

Investigators

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