2020ApJ...905L..19B

We report Chandra observations of the highly asymmetric core-collapse supernova remnant G350.1-0.3. We document expansion over 9 yr away from the roughly stationary central compact object, with sky-plane velocities up to 5000 d_4.5 km s^–1 (d_4.5is the distance in units of 4.5 kpc), redshifts ranging from 900 to 2600 km s^–1, and three-dimensional space velocities approaching 6000 km s^–1. Most of the bright emission comes from heavy-element ejecta particularly strong in iron. Iron-enhanced ejecta are seen at 4000-6000 km s^–1, strongly suggesting that the supernova was not a common Type IIP event. While some fainter regions have roughly solar abundances, we cannot identify clear blast-wave features. Our expansion proper motions indicate that G350.1-0.3 is no more than about 600 yr old, independent of distance: the third youngest known core-collapse supernova in the Galaxy, and one of the most asymmetric.