We present a polarimetric study of the pulsar wind nebula (PWN) in supernova remnant G21.5-0.9, using archival Very Large Array data taken at 5 and 7.4 GHz. The rotation measure (RM) map of the PWN shows a symmetric pattern that aligns with the presumed pulsar spin axis direction, implying a significant contribution to the RM from the nebula. We suggest that the spatial variation of the internal RM is mostly caused by the nonuniform distribution of electrons originating from the supernova ejecta. Our high-resolution radio polarization .... [...]

Lai, P.C.W.. et al. 2022, ApJ, 930, 1

Understanding the evolution of a supernova remnant shell in time is fundamental. Such understanding is critical to build reliable models of the dynamics of the supernova remnant shell interaction with any pulsar wind nebula it might contain. Here, we perform a large study of the parameter space for the 1D spherically symmetric evolution of a supernova remnant, accompanying it by analytical analysis. Assuming, as is usual, an ejecta density profile with a power-law core and an envelope, and a uniform ambient medium, we provide a set of highly accurate approximations ..... [...]

R. Bandiera et al., 2022, MNRAS, 508, 3194

We study the partial fragmentation of a strange quark star into strangelets during the process of merger of two strange quark stars. We discuss the fate of the fragments considering their possible evaporation into nucleons. We show that only a rather small amount of large size strangelets, ejected from the spiral arms in the post-merger, survives a total evaporation into nucleons. In this way we demonstrate that: 1) the density of strangelets in the galaxy is too low to trigger the conversion of all neutron stars into strange quark stars ...... [...]

N. Bucciantini et al., 2022, PRD in press