Core-collapse supernova inside the core of a young massive star cluster: 3D MHD simulations

Abstract

Young massive stars in compact stellar clusters could end their evolution as core-collapse supernovae a few million years after the cluster was built. The blast wave of a supernova propagates through the inner cluster region with multiple stellar winds of young luminous stars. We present the results of 3D magnetohydrodynamic simulations of the plasma flows produced by a supernova event inside a cluster with a population of massive stars similar to that in Westerlund 1. We followed its evolution over a few thousand years (i.e. a few shock crossing times). The plasma temperature, density, and magnetic field, which are highly disturbed by supernova event, relax to values close to the initial over the studied period. The relaxation time of a cluster is a few thousand years, which is a sizeable fraction of the period between the successive supernova events for a massive cluster of a few million years age. The spectra of the cluster diffuse X-ray emission simulated here should be representative for the galactic and extragalactic young massive clusters. The resultant magnetic fields are highly intermittent, so we derived the volume filling factors for a set of magnetic field ranges. Highly amplified magnetic fields of magnitude well above 100 µG fill in a few per cent of the cluster volume, but still dominate the magnetic energy. The structure of the magnetic fields and high-velocity plasma flows with shocks in the system are favourable for both proton and electron acceleration to energies well above TeV.

Very-high-energy γ-Ray Emission from Young Massive Star Clusters in the Large Magellanic Cloud

“…For most of our discussion, we will assume a connection between the γ-ray emission and the YMCs LH 90 38 and R136. This does not exclude scenarios in which an SN explodes inside the SB formed by the clusters; the inevitable interaction of the SN shock with the YMC and its environment distinguishes this case from a "normal," isolated SNR (Badmaev et al 2024). Alternative origins of the γ-ray emission from the newly detected source HESS J0538−691 will be discussed at the end of this section.…”