JET Formation in Solar Atmosphere Due to Magnetic Reconnection

Abstract

Using numerical simulations, we show that jets with features of type II spicules and cold coronal jets corresponding to temperatures 10 4 K can be formed due to magnetic reconnection in a scenario in presence of magnetic resistivity. For this we model the low chromosphere-corona region using the C7 equilibrium solar atmosphere model and assuming Resistive MHD rules the dynamics of the plasma. The magnetic filed configurations we analyze correspond to two neighboring loops with opposite polarity. The separation of the loops' feet determines the thickness of a current sheet that triggers a magnetic reconnection process, and the further formation of a high speed and sharp structure. We analyze the cases where the magnetic filed strength of the two loops is equal and different. In the first case, with a symmetric configuration the spicules raise vertically whereas in an asymmetric configuration the structure shows an inclination. With a number of simulations carried out under a 2.5D approach, we explore various properties of excited jets, namely, the morphology, inclination and velocity. The parameter space involves magnetic field strength between 20 and 40 G, and the resistivity is assumed to be uniform with a constant value of the order 10 −2 Ω · m.

A Three-dimensional Magnetohydrodynamic Simulation of the Formation of Solar Chromospheric Jets with Twisted Magnetic Field Lines

“…The shock-transition region interaction is slightly modified by the existence of the magnetic field in the magneto-acoustic shock wave (Hollweg et al 1982). Magnetic reconnection has also been suggested as an energy source for acoustic wave generation (Uchida 1969;Pikel'ner 1969Pikel'ner , 1971Heggland et al 2009;Singh et al 2011;González-Avilés et al 2017). The magnetic reconnection model has the advantage of chromospheric jets being accelerated by both the shock wave and the Lorentz force (Takasao et al 2013).…”

Use of Genetic Algorithms to solve Inverse Problems in Relativistic Hydrodynamics

“…We calculate this numerical solution using a High Resolution Shock Capturing method, with a method of lines that uses the Harten-Lax-van Leer-Einfeldt flux formula, minmod reconstructor and third order Runge-Kutta time integrator (see for instance [8,9,10] for some applications). …”

Magnetic Shocks and Substructures Excited by Torsional Alfvén Wave Interactions in Merging Expanding Flux Tubes

“…Type I spicules are suggested to be shock-driven and have lifetimes on the order of 3-7m i n u t e s (De Pontieu et al 2004 ) structures that are thought to form due to reconnection (e.g., de Pontieu et al 2007;Rouppe van der Voort et al 2009;González-Avilés et al 2017a).T h i s classification into two classes is controversial since spicules are multithermal and traverse multiple wavelengths (Zhang et al 2012;Pereira et al 2014). Spicules have been observed to separate into smaller magnetic substructures (Sterling et al 2010b).…”

“…Observations by Skogsrud et al (2014) imply that spicules are multithreaded. Analytical and numerical modeling has found that spicules (and spicule-type structures) can be driven in a number of ways, including magnetohydrodynamic (MHD) turbulence (Cranmer & Woolsey 2015), p-modes (De Pontieu et al 2004;Martínez-Sykora et al 2009), shock rebounds (Hollweg 1982;M u r a w s k i&Z a q a r a s h v i l i2010), magnetic reconnection (González-Avilés et al 2017a, 2017b, and granular buffeting (Roberts 1979).…”