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arXiv · 2504.10599

Dust continuum radiation maps from MHD simulations of accretion-ejection systems around single and binary stars

Abstract

We study the launching of magnetized jets from a resistive circumstellar disk within a binary system, employing a unique combination of 3D MHD jet launching simulations (PLUTO code) and post-processed 3D radiative transfer modeling (RADMC-3D code). Our findings reveal a well-defined jet originating from the inner region of the disk, extending to a larger disk area. While the model attains steady states for a single star, a binary system leads to the emergence of tidal effects such as the formation of ``spiral arms'' in the disk and inside the jet. Here we have consistently implemented a time-dependent Roche potential for the gravity of the binary. As a major step forward, we further present the first 3D radiation maps of the dust continuum for the disk-jet structure. In principle, this allows us to compare MHD simulation results to observed disk-outflow features. We, therefore, present convolved images of the dust continuum emission, employing exemplary point spread functions of the MIRI instrument (5~$μm$ band) and the ALMA array (320~$μm$ band). In these bands, we identify distinguishable features of the disk-jet structure, such as "spiral arms," which we have also seen in the MHD dynamics.For gas density increased by an order of magnitude, the disk become optically thick at 5~$μm$, but remains bright at 320~$μ$m. At this wavelength, 320~$μ$m, enhanced structural features in the disk and the base of the wind become more pronounced and are well resolved in the convolved image.

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Somayeh Sheikhnezami, Christian Fendt, Sareh Ataiee. 2025-04-14. Dust continuum radiation maps from MHD simulations of accretion-ejection systems around single and binary stars. https://arxiv.org/abs/2504.10599

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