Identifying a point-symmetrical morphology in the core-collapse supernova remnant W44

TL;DR

This paper identifies a point-symmetrical morphology in supernova remnant W44, supporting the jittering jet explosion mechanism as the primary process in core-collapse supernovae.

Contribution

It provides new morphological evidence of multiple jet pairs shaping supernova remnants, reinforcing the jittering jet explosion mechanism hypothesis.

Findings

Point-symmetrical structure in W44's radio map.

Evidence for two or more jet pairs involved in the explosion.

Inner filaments suggest a possible third jet pair.

Abstract

I identify a point-symmetrical morphology in the core-collapse supernova remnant (CCSNR) W44 compatible with shaping by three or more pairs of jets in the jittering jet explosion mechanism (JJEM). Motivated by recent identifications of point-symmetrical morphologies in CCSNRs and their match to the JJEM, I revisit the morphological classification of CCSNR W44. I examine a radio map of W44 and find the outer bright rim of the radio map to possess a point-symmetric structure compatible with shaping by two energetic pairs of opposite jets rather than an S-shaped morphology shaped by a precessing pair of jets. An inner pair of filaments might hint at a third powerful pair of jets. More pairs of jets were involved in the explosion process. This study adds to the growing evidence that the JJEM is the primary explosion mechanism of core-collapse supernovae.