Polymeric jets throw light on the origin and nature of the forest of solar spicules

TL;DR

This paper uses numerical simulations and laboratory experiments to explore the origin of solar spicules, revealing that nonlinear wave focusing in magnetized plasma and polymeric fluids can produce jet-like structures similar to those observed on the Sun.

Contribution

It demonstrates a novel analogy between solar spicule formation and polymeric fluid jets under harmonic forcing, providing new insights into jet generation mechanisms.

Findings

Simulated solar spicule forests match observations.

Polymeric fluid jets exhibit similar behavior to solar spicules.

Nonlinear wave focusing explains jet ubiquity in both systems.

Abstract

Spicules are plasma jets, observed in the dynamic interface region between the visible solar surface and the hot corona. At any given time, it is estimated that about 3 million spicules are present on the Sun. We find an intriguing parallel between the simulated spicular forest in a solar-like atmosphere and the numerous jets of polymeric fluids when both are subjected to harmonic forcing. In a radiative magnetohydrodynamic numerical simulation with sub-surface convection, solar global surface oscillations are excited similarly to those harmonic vibrations. The jets thus produced match remarkably well with the forests of spicules detected in observations of the Sun. Taken together, the numerical simulations of the Sun and the laboratory fluid dynamics experiments provide insights into the mechanism underlying the ubiquity of jets: the nonlinear focusing of quasi-periodic waves in anisotropic media of magnetized plasma as well as polymeric fluids under gravity is sufficient to generate a forest of spicules on the Sun.