MAMA: An Algebraic Map for the Secular Dynamics of Planetesimals in Tight Binary Systems

Abstract

We present an algebraic map (MAMA) for the dynamical and collisional evolution of a planetesimal swarm orbiting the main star of a tight binary system (TBS). The orbital evolution of each planetesimal is dictated by the secular perturbations of the secondary star and gas drag due to interactions with a protoplanetary disk. The gas disk is assumed eccentric with a constant precession rate. Gravitational interactions between the planetesimals are ignored. All bodies are assumed coplanar. A comparison with full N-body simulations shows that the map is of the order of 100 times faster, while preserving all the main characteristics of the full system. In a second part of the work, we apply MAMA to the γ-Cephei, searching for friendly scenarios that may explain the formation of the giant planet detected in this system. For low-mass protoplanetary disks, we find that a low-eccentricity static disk aligned with the binary yields impact velocities between planetesimals below the disruption threshold. All other scenarios appear hostile to planetary formation.

References in corpus (5)

• Relative velocities among accreting planetesimals in binary systems: the circumprimary case
• Planetesimal and gas dynamics in binaries
• Planet Formation in Binary Stars: The case of Gamma Cephei
• Planet formation in small separation binaries: not so excited after all
• Secular dynamics of planetesimals in tight binary systems: Application to Gamma-Cephei

Cited by in corpus (5)

• Planet formation in stellar binaries I: planetesimal dynamics in massive protoplanetary disks
• Birth Locations of the Kepler Circumbinary Planets
• Spiral patterns in planetesimal circumbinary disks
• Secular Orbit Evolution in Systems with a Strong External Perturber - A Simple and Accurate Model
• Dynamic portrait of the region occupied by the Hungaria Asteroids: The influence of Mars