"Studying the coronal heating problem using numerical simulations"

LAURA MORALES

Resistencia

Congreso; XXXVII Congreso Argentino de Mecánica Computacional; 2021

AMSA

The Sun is a typical magnetic star our galaxy with a surface temperature of 5000 K. The Sun’satmosphere is extremely hot (106to 107K) and is composed of a thin, highly magnetized and stratifiedplasma. The outermost layer of the solar atmosphere is the corona. A great variety of transientphenomena take place there. One of these phenomena are solar flares or flares. When they occur, thecoronal plasma is heated locally to temperatures of the order of 107K in extremely short times .In 1988 Parker suggested that the mechanism magnetic reconnection is the mechanism that dominatesthe release of energy. The coronal magnetic fields anchored in the turbulent photospheric plasmasuffers strong deformations forming complex sheets of currents. When the intensity of the currentincreases beyond a certain threshold, the magnetic reconnection phenomenon dominates (locally) thecoronal dynamics and the magnetic energy is released in the form of kinetic energy and thermal energy(Parker, 1988 & Parker, 1983 ).Two alternative approaches have been developed in order to evaluate the predictive capacity of Parker’smodel: the first assumes that the coronal plasma is a magnetic fluid that can be described by theequations of magnetohydrodynamics, and in the second the hypothesis is that the solar corona is in astate of self-organized criticality and the dynamics of the coronal magnetic field can be modeled througha cellular automaton. In this work we will present both approaches and discuss their strengths andweaknesses with particular interest the prediction of solar flares and their impact on space weather.