English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

One of the youngest known remnants of a core-collapse supernova (SN) in ourGalaxy is G320.4$-$1.2/MSH 15-52 containing an energetic pulsar with a veryshort (1700 yr) spindown age and likely produced by a stripped-envelope SN Ibc.Bright X-ray and radio emission north of the pulsar overlaps with an H$\alpha$nebula RCW 89. The bright X-rays there have a highly unusual and quite puzzlingmorphology, consisting of both very compact thermally emitting knots and muchmore diffuse emission of nonthermal origin. We report new X-ray observations ofRCW 89 in 2017 and 2018 with Chandra that allowed us to measure the motions ofmany knots and filaments on decade-long time baselines. We identify a fastblast wave with a velocity of $(4000 \pm 500)d_{5.2}$ km/s ($d_{5.2}$ is thedistance in units of 5.2 kpc) with a purely nonthermal spectrum, and withoutany radio counterpart. Many compact X-ray emission knots are moving vary fast,with velocities as high as 5000 km/s, predominantly radially away from thepulsar. Their spectra show that they are Ne- and Mg-rich heavy-element SNejecta. They have been significantly decelerated upon their recent impact withthe dense ambient medium north of the pulsar. We see fast evolution inbrightness and morphology of knots in just a few years. Ejecta knots in RCW 89resemble those seen in Cas A at optical wavelengths in terms of their initialvelocities and densities. They might have the same origin, still not understoodbut presumably related to stripped-envelope SN explosions themselves.

Fast Blast Wave and Ejecta in the Young Core-Collapse Supernova Remnant MSH 15-52/RCW 89