SCIENCE GOALS AND OBJECTIVES: OBSERVATIONAL AND THEORETICAL STUDIES IN RECENT YEARS HAVE DEMONSTRATED THAT THE INITIATION AND PROPAGATION OF SOLAR ERUPTIONS LEADING TO CORONAL MASS EJECTIONS (CMES) ARE CLOSELY ASSOCIATED WITH THE STRUCTURE OF BOTH THE CORE FIELDS AND THE LARGER SCALE FIELDS ABOVE THEM. IT HAS BEEN FOUND THAT WHILE MOST OF ERUPTIONS EVENTUALLY DEVELOP INTO CMES MANY END UP WITH CONFINED (OR FAILED) ERUPTIONS. THE PHYSICAL MECHANISMS UNDERLYING THE FILAMENT ACTIVATION AND THE ENSUING ERUPTION ARE CLOSELY RELATED TO THE KINK AND TORUS FLUX ROPE INSTABILITIES WHICH ARE DEPENDENT ON THE PROPERTIES OF THE CORE FLUX ROPE FIELDS AND THE OVERLYING ARCADE FIELDS. ALTERNATIVELY AN ERUPTION MIGHT BE DUE TO MAGNETIC RECONNECTION THAT MAY FORM NEW UNSTABLE FLUX ROPES. FINALLY IT IS RECENTLY DEMONSTRATED THAT MANY EVENTS GENERATE QUASI-CIRCULAR FLARES. THEY DO NOT FIT INTO CLASSICAL TWO-RIBBON FLARE MODEL BUT CAN BE EXPLAINED BY SPINE-FAN 3-D STRUCTURE. IN THIS PROPOSAL WE EMPLOY A UNIQUE APPROACH BASED ON A COMBINATION OF NUMERICAL SIMULATIONS OBSERVATIONS AND LABORATORY EXPERIMENTS TO ATTACK THE PROBLEMS OF THE TRIGGERING AND EVOLUTION OF SOLAR ERUPTIONS. WE PLAN TO ANSWER THE FOLLOWING SPECIFIC BUT RELATED QUESTIONS: (1) WHAT ARE IMPORTANT FACTORS IN STORING MAGNETIC ENERGY AND TRIGGERING SOLAR ERUPTIONS? (2) WHY SOME OF THE ERUPTIONS LEAD TO MAJOR CMES AND SOME OF THEM ARE CONFINED? (3) HOW DO THE MAGNETIC FIELDS EVOLVE DURING AND AFTER ERUPTIVE OR CONFINED EVENTS? METHODOLOGY: (1) PRE-ERUPTION CONDITIONS: FOR SELECTED EVENTS INCLUDING BOTH ERUPTIVE AND CONFINED ERUPTIONS THE PROPERTIES OF THE CORE FIELDS IN FLUX ROPES AND THE ARCADE FIELDS ABOVE THE FLUX ROPES WILL BE DERIVED USING THREE DIFFERENT NON-LINEAR FORCE-FREE FIELD (NLFFF) EXTRAPOLATIONS BASED ON SDO/HMI VECTOR MAGNETOGRAMS OF THE SOURCE ACTIVE REGIONS. 3D MAGNETIC SKELETON AND FULL BLOWN TOPOLOGY ANALYSIS OF THE TIME EVOLUTION OF PRE-ERUPTIVE CONFIGURATIONS WILL BE ANALYZED. FLOWS AND MAGNETIC STRUCTURE IN FLARE CORE REGIONS WILL BE DERIVED USING NEW SOLAR TELESCOPE AT BBSO. IN ADDITION WE WILL CORRELATE RECONNECTION PARAMETERS DERIVED FROM RIBBONS WITH Q FACTORS AT 3D QSLS. (2) MHD MODELING. TWO INDEPENDENT CODES WILL BE RUN FOR SAME EVENTS. (2A) WE WILL CARRY OUT PARAMETER STUDY OF CRITICAL TORUS N-INDEX OF OVERLAYING ARCADE AND GEOMETRIES OF FLUX ROPES IN KLIEM S MHD CODE INCORPORATING BOTH IDEALIZED CONFIGURATIONS AND DATA-CONSTRAINED FLUX-ROPE EMBEDDED MODELS FROM THE CFA THUS PRODUCING DATA-CONSTRAINED MHD SIMULATIONS. (2B) THE DATA-DRIVEN UAH MODEL IS USED TO NUMERICALLY SOLVE THE FULL SET OF TIME-DEPENDENT 3D MHD EQUATIONS WITH THE BOTTOM BOUNDARY CONDITIONS DRIVEN BY OBSERVED PHOTOSPHERIC MAGNETOGRAMS. OUTPUTS IN TWO MODELS ARE COMPARED AND USED IN A COMPLEMENTARY FASHION. (3) THE OBSERVATIONAL AND MODELING RESULTS WILL BE COMPARED WITH THE PPPL EXPERIMENTAL RESULTS. THE PROPERTIES OF THE CORE AND STRAPPING FIELDS IN THE LAB EXPERIMENTS FOR STABLE AND UNSTABLE REGIMES WILL BE COMPARED WITH SPECIFIC CONFIGURATIONS FOR ERUPTIVE AND CONFINED EVENTS. THE RESEARCH IS CLOSELY RELEVANT TO ONE OF THE HELIOPHYSICS DECADAL SURVEY GOALS: DETERMINE THE ORIGINS OF THE SUN'S ACTIVITY AND PREDICT THE VARIATIONS IN THE SPACE ENVIRONMENT. OUR PROPOSED RESEARCH WILL CLEARLY ANSWER SOME OF THE MOST CRITICAL QUESTIONS ABOUT THE INITIATION AND DEVELOPMENT OF SOLAR ERUPTIONS WHICH WILL EXTEND THE FRONTIER OF THE EXISTING KNOWLEDGE ON THE ENERGY RELEASE PHYSICS OF FLARES/CMES AND ASSOCIATED CORONAL FIELD RECONFIGURATION.