DYNAMICS OF SOLAR FLARES: COMBINING NASA SPACE DATA WITH MICROWAVE IMAGING SPECTROSCOPY

OBJECTIVES OF THE PROJECT: THIS PROPOSAL SEEKS SUPPORT FOR A FOCUSED PROGRAM OF FUNDAMENTAL RESEARCH ON SOLAR FLARE DYNAMICS VIA ANALYSIS OF NASA DATA AUGMENTED BY MICROWAVE IMAGING SPECTROSCOPY AND ADVANCED 3D MODELING AND FORWARD FITTING. A SPECIFIC GOAL OF THE PROJECT IS TO OBTAIN QUANTITATIVE INFORMATION OF HOW THE PARAMETERS OF THE SOLAR FLARES SUCH AS MAGNETIC FIELD AND FAST ELECTRON DISTRIBUTION EVOLVE ON THE TIME SCALE DOWN TO 1 S USE THIS INFORMATION TO INFER THE BASIC PROCESSES OCCURRING IN FLARES AND SUPPLY THE NASA COMMUNITY WITH THE DATA DATA PRODUCTS AND RESULTS OF ANALYSIS THEREOF. SIGNIFICANCE: THIS PROPOSAL ADDRESSES ONE OF THE MOST FUNDAMENTAL HIGH PRIORITY PROBLEMS IN SOLAR PHYSICS: THE BASIC MECHANISMS OF SOLAR FLARES INCLUDING INITIATION AND SUBSEQUENT SPATIAL AND TEMPORAL EVOLUTION OF ENERGETIC PARTICLES OVER A WIDE RANGE OF ENERGY FROM THERMAL TO RELATIVISTIC. THIS RESEARCH IS TIMELY: THE UNIQUE COMBINATION OF RHESSI AND SDO PROVIDING THE DIAGNOSTICS ON THE NONTHERMAL ELECTRONS THERMAL PLASMA AND CONTEXT MAGNETIC FIELD CAN NOW BE COMPLEMENTED BY DIAGNOSTICS OF MAGNETIC FIELD ALONG FLARING LOOPS AVAILABLE FROM MICROWAVE IMAGING SPECTROSCOPY OF FLARES ALREADY OBSERVED WITH OUR EXPANDED OWENS VALLEY SOLAR ARRAY (EOVSA). RELEVANCE TO NASA: THIS PROPOSAL ADDRESSES THE NASA STRATEGIC GOAL TO UNDERSTAND THE SUN AND ITS INTERACTIONS WITH THE EARTH AND THE SOLAR SYSTEM AND THE NASA-SPECIFIC RESEARCH OBJECTIVE TO UNDERSTAND THE FUNDAMENTAL PHYSICAL PROCESSES OF THE SPACE ENVIRONMENT FROM THE SUN TO EARTH TO OTHER PLANETS AND BEYOND TO THE INTERSTELLAR MEDIUM. THE FOCUSED PROGRAM OF SOLAR FLARE STUDIES WITH MULTI-WAVELENGTH DATA AS PROPOSED HERE IS EXPLICITLY AND HIGHLY RELEVANT TO THE FIRST GOAL OF THE HELIOPHYSICS DECADAL SURVEY DETERMINE THE ORIGINS OF THE SUN S ACTIVITY AND PREDICT THE VARIATIONS IN THE SPACE ENVIRONMENT AND TO THE FOURTH DECADAL SURVEY GOAL DISCOVER AND CHARACTERIZE FUNDAMENTAL PROCESSES THAT OCCUR BOTH WITHIN THE HELIOSPHERE AND THROUGHOUT THE UNIVERSE. METHODOLOGY: WE EMPLOY A COMBINATION OF THE HXR DATA ON THE NONTHERMAL ELECTRONS EUV DATA ON THE THERMAL PLASMA AND CONTEXT MAGNETIC FIELD DATA WITH AUXILIARY CORONAL MAGNETIC FIELD MEASUREMENTS AVAILABLE FROM MICROWAVE IMAGING SPECTROSCOPY. THE CORONAL MAGNETOMETRY METHOD WHICH WE HAVE RECENTLY DEVELOPED WILL BE APPLIED TO SPATIALLY RESOLVED MICROWAVE SPECTRA PROVIDED BY EOVSA ONCE PER SECOND OVER>100 SPECTRAL CHANNELS TO BE ADDED TO THE PRIMARY NASA DATA ON FLARE HEATED AND ACCELERATED PARTICLES. THE COMBINED DATA ARE USED FOR DATA-DRIVEN FORWARD-FIT 3D MODELING MATCHING ALL THE AVAILABLE OBSERVATIONAL DATA. TEAM: TO ATTACK THE PROJECT OBJECTIVES WE BRING TOGETHER A HIGHLY QUALIFIED TEAM OF EXPERIENCED RESEARCHERS WHICH COLLECTIVELY POSSESS ALL NEEDED EXPERTISE TO FULLY ACHIEVE THE PROJECT GOALS. PROPOSED WORK: WE WILL STUDY HEATING ACCELERATION AND TRANSPORT OF THERMAL AND NONTHERMAL ELECTRONS VIA COMPREHENSIVE DATA ANALYSIS AUGMENTED BY TIME-DEPENDENT 3D MODELING OF A NUMBER OF SOLAR FLARES JOINTLY OBSERVED BY RHESSI SDO EOVSA AND OTHER INSTRUMENTS WHICH WILL INCLUDE SUCH CLOSELY INTERACTING ELEMENTS AS NONLINEAR FORCE-FREE EXTRAPOLATIONS CORONAL THERMAL STRUCTURE SIMULATION OF THE OBSERVED EMISSIONS COMPARISON WITH OBSERVATIONS AND ITERATIVE IMPROVEMENTS OF THE ENTIRE FLARE MODEL. THEORY AND SPECIFIC MODEL ELEMENTS WILL BE UPDATED AS GUIDED BY THE NEEDS OF DETAILED UNDERSTANDING OF THE FLARE DATA. COST EFFECTIVENESS: THIS PROJECT (I) LEVERAGES MANY MODELING ELEMENTS AND TOOLS FROM PRIOR NASA AND NSF SUPPORT SUCH AS GX SIMULATOR TOOL AND (II) UTILIZES NEW DATA NOW AVAILABLE FROM EOVSA CONSTRUCTED UNDER DEDICATED NSF SUPPORT. DATA POLICY: ALL DATA PRODUCTS AND INTERMEDIATE RESULTS FROM THIS RESEARCH SUCH AS PARAMETER MAPS AND EVEN THE 3D MODELS WILL BE PUBLICLY AVAILABLE TO EMPOWER OTHERS AROUND THE NATION AND WORLD TO CONTRIBUTE TO THE NASA HELIOPHYSICS SCIENCE GOALS.