# Modeling a Carrington-scale Stellar Superflare and Coronal Mass Ejection from $\kappa^{1}Cet$

## TL;DR

This paper models a massive stellar superflare and associated coronal mass ejection from $$ Cet, revealing how magnetic energy buildup can produce events comparable to historic solar flares, with significant implications for exoplanet habitability.

## Contribution

It introduces a 3D magnetohydrodynamic model of a Carrington-scale superflare on a young solar-like star, linking magnetic shear to extreme energy release and space-weather effects.

## Key findings

- Superflare energy comparable to the 1859 Carrington event.
- Synthetic emission and shock signatures suggest extreme space-weather impacts.
- The 1986 Robinson-Bopp superflare may have been as extreme as the Carrington event for $$ Cet.

## Abstract

Observations from the Kepler mission have revealed frequent superflares on young and active solar-like stars. Superflares result from the large-scale restructuring of stellar magnetic fields, and are associated with the eruption of coronal material (a coronal mass ejection, or CME) and energy release that can be orders of magnitude greater than those observed in the largest solar flares. These catastrophic events, if frequent, can significantly impact the potential habitability of terrestrial exoplanets through atmospheric erosion or intense radiation exposure at the surface. We present results from numerical modeling designed to understand how an eruptive superflare from a young solar-type star, $\kappa^{1}Cet$, could occur and would impact its astrospheric environment. Our data-inspired, three-dimensional magnetohydrodynamic modeling shows that global-scale shear concentrated near the radial-field polarity inversion line can energize the closed-field stellar corona sufficiently to power a global, eruptive superflare that releases approximately the same energy as the extreme 1859 Carrington event from the Sun. We examine proxy measures of synthetic emission during the flare and estimate the observational signatures of our CME-driven shock, both of which could have extreme space-weather impacts on the habitability of any Earth-like exoplanets. We also speculate that the observed 1986 Robinson-Bopp superflare from $\kappa^{1}Cet$ was perhaps as extreme for that star as the Carrington flare was for the Sun.