Magnetar-Powered Supernovae in Two Dimensions. I. Superluminous Supernovae

TL;DR

This study explores how magnetar energy injection influences supernova structure and appearance in two dimensions, revealing persistent shell-like features despite instabilities that cause mixing and filamentation.

Contribution

It extends previous one-dimensional models to two dimensions, demonstrating the persistence of a dense shell and its effects on supernova observables and remnant morphology.

Findings

Instabilities cause filamentary mixing but do not destroy the dense shell.

The degree of mixing depends on magnetar energy and ejecta kinetic energy.

Supernova light curves and spectra are significantly affected by these dynamics.

Abstract

Previous studies have shown that the radiation emitted by a rapidly rotating magnetar embedded in a young supernova can greatly amplify its luminosity. These one-dimensional studies have also revealed the existence of an instability arising from the piling up of radiatively accelerated matter in a thin dense shell deep inside the supernova. Here we examine the problem in two dimensions and find that, while instabilities cause mixing and fracture this shell into filamentary structures that reduce the density contrast, the concentration of matter in a hollow shell persists. The extent of the mixing depends upon the relative energy input by the magnetar and the kinetic energy of the inner ejecta. The light curve and spectrum of the resulting supernova will be appreciably altered, as will the appearance of the supernova remnant, which will be shellular and filamentary. A similar pile up and mixing might characterize other events where energy is input over an extended period by a centrally concentrated source, e.g. a pulsar, radioactive decay, a neutrino-powered wind, or colliding shells. The relevance of our models to the recent luminous transient ASASSN-15lh is briefly discussed.