2025/11/27 by Dhruv Muley, L.-A. Hühn, Muley, Dhruv +5
Physics and Astronomy · #Accretion (finance) #Astro and Planetary Science #Astrophysics and Star Formation Studies #Earth and Planetary Astrophysics (astro-ph.EP) #Enhanced Data Rates for GSM Evolution #Excitation #FOS: Physical sciences #Feature (linguistics) #Instrumentation and Methods for Astrophysics (astro-ph.IM) #Isotopologue #Kinematics #Radiative transfer #Solar and Stellar Astrophysics (astro-ph.SR) #Spiral (railway) #Spiral galaxy #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.2511.22527
openalex publication_date 2025/11/27 · openalex created_date 2025/12/03 · openalex updated_date 2026/08/05
High-resolution, near-infrared observations have revealed prominent, two-armed spirals in a multitude of systems, such as MWC~758, SAO~206462, and V1247~Ori. Alongside the classical theory of disk-companion interaction, shadow-based driving has come into vogue as a potential explanation for such large-scale substructures. How might these two mechanisms be distinguished from one another in observations? To investigate this question, we ran a pair of hydrodynamical simulations with PLUTO. One, with full radiation hydrodynamics and gas-grain collision, was designed to develop shadow-driven spirals at the outer gap edge of a sub-thermal, Saturn-mass planet. The other, with parametrized β-cooling, was set up to capture the more standard view of spiral wave excitation by a super-thermal, multi-Jupiter-mass, exterior planetary companion. Post-processing of these simulations with the Monte Carlo radiative transfer (MCRT) code RADMC3D revealed that strong vertical velocities in the shadow-driven case create a prominent two-armed feature in the moment-1 CO maps, particularly when the disk is viewed face-on in optically thicker isotopologues; such a feature is not seen in the standard planet-driven case. Conversely, the presence or absence of such signatures in two-armed spiral systems would distinguish those potentially driven by exterior, multi-Jupiter-mass companions, and thus help identify promising targets for future direct-imaging campaigns.