Two step chromospheric Moreton wave excitation in a blast-wave scenario. A case study: the December 06, 2006 event

TL;DR

This study investigates whether blast-wave scenarios related to flares or CME expansions can reproduce chromospheric Moreton waves, using simulations of the December 6, 2006 event to compare models with observations.

Contribution

It demonstrates that both flare-induced blast-waves and CME flank expansions can generate observable Moreton waves under realistic coronal conditions.

Findings

A low magnetic field in the corona is necessary for strong shock formation.

Both flare blast-waves and CME flank expansions can reproduce observed Moreton waves.

Simulations match the December 6, 2006 event observations.

Abstract

We examine the capability of a blast-wave scenario -associated to a coronal flare or to the expansion of CME flanks- to reproduce a chromospheric Moreton phenomenon. We also simulate the Moreton event of December 06, 2006 considering both the corona and the chromosphere. To obtain a sufficiently strong coronal shock -able to generate a detectable chromospheric Moreton wave- a relatively low magnetic field intensity is required, in comparison with the active region values. Employing reasonable coronal constraints, we show that a flare ignited blast-wave or the expansion of the CME flanks emulated as an instantaneous or a temporal piston model, respectively, are capable to reproduce the observations.