Observational signatures of planetary tidal disruption events around solar-mass stars

¹ Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso, Chile
² School of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
³ Fakultät für Physik, Universität Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany
⁴ Research Institute of Physics, Southern Federal University, Rostov-on-Don 344090, Russia
⁵ Instituto de Física y Astronomía, Universidad de Valparaíso, ave. Gran Bretaña, 1111, Casilla 5030, Valparaíso, Chile
⁶ Millennium Institute of Astrophysics, Nuncio Monseñor Sotero Sanz 100, Of. 104, Providencia, Santiago, Chile
⁷ Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
⁸ European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany
⁹ Department of Physics and Astronomy, University of Nevada, Las Vegas, 4505 S. Maryland Pkwy, Las Vegas, NV 89154, USA
¹⁰ Nevada Center for Astrophysics, University of Nevada, Las Vegas, 4505 S. Maryland Pkwy., Las Vegas, NV 89154-4002, USA

^★ Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 3 December 2025
Accepted: 16 January 2026

Abstract

Context. The tidal disruption of planets by their host stars represents a growing area of interest in transient astronomy, offering insights into the final stages of planetary system evolution and the scattering of planets in gas-poor environments.

Aims. We aim to model the hydrodynamic evolution and predict the multiwavelength observational signatures of planetary tidal disruption events (TDEs) around a solar-mass host, focusing on Jupiter-like and Neptune-like progenitors and examining how different eccentricities of the planet’s pre-disruption orbit shape the morphology and emission of the tidal debris.

Methods. We performed 2D hydrodynamic simulations using the FARGO3D code to model the formation and viscous evolution of the resulting debris disk. We employed a viscous α-disk prescription and included a time-dependent energy equation to compute the disk’s effective temperature and subsequently derive the bolometric and multiband photometric light curves.

Results. Our simulations show that planetary TDEs produce a diverse range of luminous transients. A Jupiter-like planet disrupted from a circular orbit at the Roche limit generates a transient that peaks at L_bol ∼10³⁸ erg s⁻¹ after a ∼12-day rise. In contrast, the same planet on an eccentric orbit (e=0.5) produces a transient of comparable peak luminosity but on a much shorter timescale, peaking in only ∼1 day, which is followed by a highly volatile light curve. We find that the effect of eccentricity is not universal, as it accelerates the event for Jupiter but delays it for Neptune. A robust “bluer-when-brighter” color evolution is a common feature as the disk cools over its multi-year lifetime.

Conclusions. The strong dependence of light curve morphology on the initial orbit and progenitor mass makes these events powerful diagnostics. The dichotomous effect of eccentricity indicates that light curves probe both orbital parameters and the planet’s internal structure. This framework is crucial for identifying planetary TDEs in time-domain surveys.