The Hill stability of inclined small mass binary systems in three-body systems with special application to triple star systems, extrasolar planetary systems and Binary Kuiper Belt systems

Although the evolution of binary systems has been qualitatively interpreted with the evolutionary scenario, the quantitative interpretation of any observed system is still unsatisfactory due to the difficulty of the quantitative treatment of mass and angular momentum transfer/loss. To reach a true understanding of the evolution of binary systems, we have to accumulate more observational evidence. So far, we have observed several binaries that are short-period and noncontact, and found the existence of extremely small-mass systems. In the present paper, we study another short-period (P=0.659d), noncontact, eclipsing binary system, V392 Ori. We have made photometric and spectroscopic observations of V392 Ori. The light curves are found to vary, suggesting the existence of circumstellar matter around the system. Combining the photometric and spectroscopic results, we obtain parameters describing the system; we find the mass of the primary component is only 0.6Mʘ- undermassive for its spectral and luminosity class A5V, suggesting that a considerable amount of its original mass has been lost from the system during the course of evolution. The low-mass problem is very important for investigation of the evolution of close binary systems: largemass loss within and/or after the main-sequence will have a significant influence on the future evolution of binary systems.

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Structural stability of CmTin microclusters and nanoparticles: Molecular–dynamics simulations

Computing Letters ◽

10.1163/157404005776611321 ◽

2005 ◽

Vol 1 (4) ◽

pp. 204-209

Author(s):

O.B. Malcıoğlu ◽

Ş. Erkoç

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Binary Systems ◽

Minimum Energy ◽

Potential Energy Function ◽

Md Simulations ◽

Atomic Interactions ◽

Dynamics Simulations ◽

Three Body ◽

Initial Geometry

The minimum energy structures of CmTin microclusters and nanoparticles have been investigated theoretically by performing molecular–dynamics (MD) simulations. Selected crystalline and completely random initial geometries are considered. The potential energy function (PEF) used in the calculations includes two– and three–body atomic interactions for C-Ti binary systems. Molecular–dynamics simulations have been performed at 1 K and 300 K. It has been found that initial geometry has a very strong influence on relaxed geometry

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Analysis of near-separatrix motion in planetary systems

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308017018 ◽

2007 ◽

Vol 3 (S249) ◽

pp. 491-498

Author(s):

Su Wang ◽

Ji-Lin Zhou

Keyword(s):

Planetary Systems ◽

Scattering Model ◽

High Occurrence ◽

Mean Motion ◽

Accretion Process ◽

Three Body ◽

Mean Motion Resonance

AbstractNear-separatrix motion is a kind of motion of two planets with their relative apsidal longitude near the boundary between libration and circulation. Observed multiple planetary systems seem to favor near-separatrix motions between neighboring planets. In this report, we study the probability that near-separatrix motion occurs with both the linear secular system and full three-body systems. We find that generally the ratio of near-separatrix motion is small unless the eccentricities of the two planets differ from each other by an order of magintude, or they are in mean motion resonance. To explore the dynamical procedures causing the near-separatrix motion, we suppose a modification to scattering model by adding a mass-accretion process during the protoplanet growth. Statistics on the modified scattering model indicate that the probability of the final planet pairs in near-separatrix motion is high (∼ 85%), which may explain the high occurrence of near-separatrix motions in observed planetary systems.

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Origin of Binary Systems

Symposium - International Astronomical Union ◽

10.1017/s0074180900122016 ◽

1992 ◽

Vol 151 ◽

pp. 9-19

Author(s):

Peter Bodenheimer

Keyword(s):

Angular Momentum ◽

Binary Systems ◽

Theoretical Calculations ◽

Pressure Effects ◽

Close Binaries ◽

Rotating Stars ◽

Multiple Systems ◽

The Individual ◽

Protostellar Collapse ◽

Three Body

Recent observational studies of the properties of binary systems among young stars indicate that the majority of binaries are formed very early in the history of a star, perhaps during the protostellar collapse. Major observational facts to be explained include the overall binary frequency, the non-negligible occurrence of multiple systems, and the distributions of period, eccentricity, and mass ratio among the individual binaries. Theoretical calculations of the collapse of rotating protostars during the isothermal phase indicate instability to fragmentation into multiple systems. This process in general produces systems with periods greater than a few hundred years, although somewhat shorter periods are possible. Fragmentation during later, optically thick, phases of collapse tends to be suppressed by pressure effects. Therefore, major theoretical problems remain concerning the origin of close binaries. Fission of rapidly rotating stars, tidal capture, and three-body capture have been shown to be improbable mechanisms for formation of close binaries. Mechanisms currently under study include gravitational instabilities in disks, orbital interactions and disk-induced captures in fragmented multiple systems, hierarchical fragmentation, and orbital decay of long-period systems. Single stars, on the other hand, could result by escape from multiple systems or by the collapse of clouds of low angular momentum, coupled with angular momentum transport after disk formation.

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Searching for a dusty cometary belt around TRAPPIST-1 with ALMA

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa266 ◽

2020 ◽

Vol 492 (4) ◽

pp. 6067-6073 ◽

Cited By ~ 2

Author(s):

S Marino ◽

M C Wyatt ◽

G M Kennedy ◽

M Kama ◽

L Matrà ◽

...

Keyword(s):

Liquid Water ◽

Kuiper Belt ◽

Dust Emission ◽

Planetary Systems ◽

Dynamical Instability ◽

Solid Mass ◽

Low Mass Stars ◽

Upper Limit ◽

Low Mass ◽

Collisional Evolution

ABSTRACT Low-mass stars might offer today the best opportunities to detect and characterize planetary systems, especially those harbouring close-in low-mass temperate planets. Among those stars, TRAPPIST-1 is exceptional since it has seven Earth-sized planets, of which three could sustain liquid water on their surfaces. Here we present new and deep ALMA observations of TRAPPIST-1 to look for an exo-Kuiper belt which can provide clues about the formation and architecture of this system. Our observations at 0.88 mm did not detect dust emission, but can place an upper limit of 23 µJy if the belt is smaller than 4 au, and 0.15 mJy if resolved and 100 au in radius. These limits correspond to low dust masses of ∼10−5 to 10−2 M⊕, which are expected after 8 Gyr of collisional evolution unless the system was born with a >20 M⊕ belt of 100 km-sized planetesimals beyond 40 au or suffered a dynamical instability. This 20 M⊕ mass upper limit is comparable to the combined mass in TRAPPIST-1 planets, thus it is possible that most of the available solid mass in this system was used to form the known planets. A similar analysis of the ALMA data on Proxima Cen leads us to conclude that a belt born with a mass ≳1 M⊕ in 100 km-sized planetesimals could explain its putative outer belt at 30 au. We recommend that future characterizations of debris discs around low-mass stars should focus on nearby and young systems if possible.

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Escaping Trajectories in the Hill Three-Body Problem and Applications

Journal of Guidance Control and Dynamics ◽

10.2514/2.5062 ◽

2003 ◽

Vol 26 (2) ◽

pp. 224-232 ◽

Cited By ~ 58

Author(s):

B. F. Villac ◽

D. J. Scheeres

Keyword(s):

Body Problem ◽

Three Body Problem ◽

Three Body ◽

The Hill

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