From Common Envelope Evolution to Luminous Red Novae I: A One-dimensional Radiation Hydrodynamic Model

Abstract

The acceleration and unbinding of the common envelope during the plunge-in phase are governed by complex physical processes that often manifest observationally as luminous red novae. We investigate the dynamics of this phase using one-dimensional radiation hydrodynamic simulations evolved with the code {\tt Guangqi}. We perform a parameter survey to quantify the impact of key physical conditions on the unbound mass fraction, $\eta$, and the resulting light curves. Our survey spans a range of radiation-to-gas internal energy ratios ($\mathcal{E}/e_{\text{g}}\in [0.2,3.2]$), ratios of total envelope energy to gravitational binding energy ($\zeta \in [0.54,2.87]$), and mass injection rates ($\dot{M}\in [2.5,10]M_{\odot }/\mathrm{yr}$), while covering both subsonic and supersonic expansion regimes ($v_{\mathrm{ej}}/v_{\mathrm{esc}}\in [0.3,0.6]$). We demonstrate that: (1) radiation pressure becomes the dominant driver of mass ejection in the high-opacity, high-luminosity region immediately below the recombination front; (2) $\eta$ exhibits a nonlinear dependence on $\zeta$, which is modulated by the mass injection rate and gravitational potential; and (3) the recombination of atomic to molecular hydrogen ($\ce{H}\to\ce{H2}$) releases latent heat that sustains a secondary plateau in the late-time light curve. These findings are substantiated by detailed error analysis and convergence testing presented in the Appendices.

Accepted by the ApJ

References in corpus (48)

• Common Envelope Evolution: Where we stand and how we can move forward
• Double Compact Objects I: The Significance Of The Common Envelope On Merger Rates
• Rosseland and Planck Mean Opacities for Protoplanetary Discs
• V1309 Scorpii: merger of a contact binary
• An AMR Study of the Common Envelope Phase of Binary Evolution
• On the alpha formalism for the common envelope interaction
• On the nature of massive helium star winds and Wolf-Rayet-type mass loss
• Hydrodynamic moving-mesh simulations of the common envelope phase in binary stellar systems
• Type Ia Supernova Explosions in Binary Systems: A Review
• V1309 SCO - Understanding a merger
• The Complete Evolution of a Neutron-Star Binary through a Common Envelope Phase Using 1D Hydrodynamic Simulations
• Luminous Red Novae: Stellar Mergers or Giant Eruptions?
• Accretion in common envelope evolution
• Common Envelope ejection for a Luminous Red Nova in M101
• Binary Population Synthesis
• Recombination energy in double white dwarf formation
• SPIRITS: Uncovering Unusual Infrared Transients With Spitzer
• Common envelope events with low-mass giants: understanding the transition to the slow spiral-in
• Common envelope events with low-mass giants: understanding the energy budget
• Common envelopes in massive stars: Towards the role of radiation pressure and recombination energy in ejecting red supergiant envelopes
• Numerical Simulations of Convective 3-Dimensional Red Supergiant Envelopes
• Evolution and Mass Loss of Cool Ageing Stars: a Daedalean Story
• Common-envelope evolution with an asymptotic giant branch star
• The limited role of recombination energy in common envelope removal
• Binary Stars in the New Millennium
• Mean gas opacity for circumstellar environments and equilibrium temperature degeneracy
• A two-stage formalism for common-envelope phases of massive stars
• The transitional gap transient AT 2018hso: new insights on the luminous red nova phenomenon
• Common Envelope Evolution on a Moving Mesh
• Bipolar planetary nebulae from common envelope evolution of binary stars
• On the optically-thick winds of Wolf-Rayet stars
• Radiating the hydrogen recombination energy during common envelope evolution
• Luminous Red Nova AT 2019zhd, a new merger in M 31
• From 3D hydrodynamic simulations of common-envelope interaction to gravitational-wave mergers
• Common envelopes in massive stars II: The distinct roles of hydrogen and helium recombination
• Properties of the post in-spiral common envelope ejecta I: dynamical and thermal evolution
• Convection and Spin-Up During Common Envelope Evolution: The Formation of Short-Period Double White Dwarfs
• The luminous red nova variety: AT 2020hat and AT 2020kog
• From spherical stars to disk-like structures: 3D common-envelope evolution of massive binaries beyond inspiral
• Panchromatic evolution of three luminous red novae: Forbidden hugs in pandemic times -- IV
• Common envelopes in massive stars III. The obstructive role of radiation transport in envelope ejection
• Simulating a stellar contact binary merger -- I. Stellar models
• Non-LTE radiation hydrodynamics in PLUTO
• Solving the Riemann Problem for Realistic Astrophysical Fluids
• Magnetically driven outflows in 3D common-envelope evolution of massive stars
• Formation of Wind-Fed Black Hole High-mass X-ray Binaries: The Role of Roche-lobe-Overflow Post Black-Hole Formation
• Two-Dimensional Radiation-Hydrodynamic Simulations of Luminous Red Novae
• Light Curve Models of Convective Common Envelopes