3D hybrid fluid-particle jet simulations and the importance of synchrotron radiative losses

Journal Article · 24 October 2024 · Astronomy and Astrophysics

DOI: https://doi.org/10.1051/0004-6361/202450978 · OSTI ID:2477198

Kramer, Joana A.  ^[1]; MacDonald, Nicholas R.  ^[2]; Paraschos, Georgios F.  ^[3]; Ricci, Luca  ^[4]

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1. Max-Planck-Institut für Radioastronomie, Bonn (Germany); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
2. Max-Planck-Institut für Radioastronomie, Bonn (Germany); Univ. of Mississippi, Oxford, MS (United States)
3. Max-Planck-Institut für Radioastronomie, Bonn (Germany)
4. Max-Planck-Institut für Radioastronomie, Bonn (Germany); Julius-Maximilians-Universität, Würzburg (Germany)

Context. Relativistic jets in active galactic nuclei are known for their exceptional energy output, and imaging the synthetic synchrotron emission of numerical jet simulations is essential for a comparison with observed jet polarization emission. Aims. Through the use of 3D hybrid fluid-particle jet simulations (with the PLUTO code), we overcome some of the commonly made assumptions in relativistic magnetohydrodynamic (RMHD) simulations by using non-thermal particle attributes to account for the resulting synchrotron radiation. Polarized radiative transfer and ray-tracing (via the RADMC-3D code) highlight the differences in total intensity maps when (i) the jet is simulated purely with the RMHD approach, (ii) a jet tracer is considered in the RMHD approach, and (iii) a hybrid fluid-particle approach is used. The resulting emission maps were compared to the example of the radio galaxy Centaurus A. Methods. We applied the Lagrangian particle module implemented in the latest version of the PLUTO code. This new module contains a state-of-the-art algorithm for modeling diffusive shock acceleration and for accounting for radiative losses in RMHD jet simulations. The module implements the physical postulates missing in RMHD jet simulations by accounting for a cooled ambient medium and strengthening the central jet emission. Results. We find a distinction between the innermost structure of the jet and the back-flowing material by mimicking the radio emission of the Seyfert II radio galaxy Centaurus A when considering an edge-brightened jet with an underlying purely toroidal magnetic field. We demonstrate the necessity of synchrotron cooling as well as the improvements gained when directly accounting for non-thermal synchrotron radiation via non-thermal particles.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: European Research Council (ERC); National Aeronautics and Space Administration (NASA); USDOE
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 2477198
• Report Number(s): LA-UR--24-22728
• Journal Information: Astronomy and Astrophysics, Journal Name: Astronomy and Astrophysics Vol. 691; ISSN 0004-6361
• Publisher: EDP SciencesCopyright Statement
• Country of Publication: United States
• Language: English