The excitation of planetary orbits by stellar jet variability and polarity reversal
arXiv:1208.1432 · doi:10.1007/s10509-012-1209-0
Abstract
Planets form in active protoplanetary disks that sustain stellar jets. Momentum loss from the jet system may excite the planets' orbital eccentricity and inclination (Namouni 2005, AJ 130, 280). Evaluating quantitatively the effects of such excitation requires a realistic modeling of the momentum loss profiles associated with stellar jets. In this work, we model linear momentum loss as a time-variable stochastic process that results in a zero mean stellar acceleration. Momentum loss may involve periodic or random polarity reversals. We characterize orbital excitation as a function of the variability timescale and identify a novel excitation resonance between a planet's orbital period and the jet's variability timescale where the former equals twice the latter. For constant variability timescales, resonance is efficient for both periodic and random polarity reversals, the latter being stronger than the former. For a time variable variability timescale, resonance crossing is a more efficient excitation mechanism when polarity reversals are periodic. Each polarity reversal type has distinct features that may help constrain the magnetic history of the star through the observation of its planetary companions. For instance, outward planet migration to large distances from parent stars is one of the natural outcomes of periodic polarity reversal excitation if resonance crossing is sufficiently slow. Applying the excitation mechanism to the solar system, we find that the planet-jet variability resonance with periodic polarity reversal momentum loss is a possible origin for the hitherto unexplained inclination of Jupiter's orbit by 6 deg. with respect to the Sun's equator.
arXiv comment16 pages, 10 figures. published in Astrophysics & Space Science
References in corpus (27)
- Shrinking binary and planetary orbits by Kozai cycles with tidal friction
- Dynamical Outcomes of Planet-Planet Scattering
- Defining and cataloging exoplanets: The exoplanet.eu database
- Dynamical Origin of Extrasolar Planet Eccentricity Distribution
- Magnetic Cycles in a Convective Dynamo Simulation of a Young Solar-type Star
- Magnetic cycles of the planet-hosting star Tau Bootis: II. a second magnetic polarity reversal
- Multiple and changing cycles of active stars II. Results
- High Orbital Eccentricities of Extrasolar Planets Induced by the Kozai Mechanism
- HST/STIS Observations of the Bipolar Jet from RW Aurigae: Tracing Outflow Asymmetries Close to the Source
- Recipes for stellar jets: results of combined optical/infrared diagnostics
- Jet rotation: launching region, angular momentum balance and magnetic properties in the bipolar outflow from RW Aur
- Excitation and Propagation of Eccentricity Disturbances in Planetary Systems
- Resonant capture by inward migrating planets
- Proper motions and velocity asymmetries in the RW Aur jet
- Tracing kinematical and physical asymmetries in the jet from DG Tau B
- Direct observation of magnetic cycles in Sun-like stars
- HST/STIS observations of the RW Aurigae bipolar jet: mapping the physical parameters close to the source
- Synchrotron and Synchrotron Self-Compton Spectral Signatures and Blazar Emission Models
- A polarity reversal in the large-scale magnetic field of the rapidly rotating Sun HD 190771
- IR diagnostics of embedded jets: velocity resolved observations of the HH34 and HH1 jets
- On the Origin of the Eccentricities of Extrasolar Planets
- IR diagnostics of embedded jets: kinematics and physical characteristics of the HH46-47 jet
- Mass loss at the lowest stellar masses
- The Accelerated Kepler Problem
- A magnetic cycle of tau Bootis? The coronal and chromospheric view
- On the Flaring of Jet-sustaining Accretion Disks
- Eccentricities of Planets in Binary Systems