The Hand of God Revisited: Revealing the Shell Structure and Jet-Supernova Remnant Interaction in MSH 15-52

Abstract: We present an X-ray analysis of the supernova remnant (SNR) MSH 15-52 associated with the young rotation-powered pulsar PSR B1509-58, using Chandra, XMM-Newton, and eROSITA, complemented by MeerKAT radio data. We report the discovery of the missing southern counterpart to the bright northern RCW 89 region and identify a foreground X-ray source that may be a previously unidentified SNR candidate. Imaging and spectroscopy with XMM-Newton and eROSITA reveal the shell properties of MSH 15-52 and suggest that both the southern and northern shell-like structures are consistent with shocked interstellar medium associated with the forward shock, while their low ionization timescales and possible hard power-law components indicate possible influence from particle injection or additional heating by the pulsar wind nebula (PWN) jets. New Chandra spectral maps of the southern jet reveal a region of hard non-thermal emission, with a photon index of approximately 1.6, suggesting interaction between the PWN and the reverse shock and possible re-acceleration of the pulsar outflow. Spatially resolved spectroscopy of the RCW 89 northern clumps reveals high-velocity, metal-rich ejecta with enhanced Ne and Mg abundances. Comparison with core-collapse nucleosynthesis models favors a massive progenitor with an initial mass of approximately 29 solar masses in one-dimensional yield models, while asymmetric explosion models show that lower-mass progenitors can also reproduce the observed abundance ratios. Our study supports a picture in which RCW 89 is part of a larger asymmetric SNR shell interacting with energetic pulsar jets, making the system a valuable laboratory for probing pulsar-PWN-SNR interaction.