scholarly journals Two-temperature Debris Disks: Signposts for Directly Imaged Planets?

2015 ◽  
Vol 10 (S314) ◽  
pp. 163-166
Author(s):  
Grant M. Kennedy ◽  
Mark C. Wyatt
Keyword(s):  
High Resolution ◽  
Dust Emission ◽  
Planetary Systems ◽  
Giant Planets ◽  
Debris Disks ◽  
Cool Component ◽  
Different Temperatures ◽  
Narrow Belt ◽  
Two Temperature

AbstractThis work considers debris disks whose spectra can be modelled by dust emission at two different temperatures. These disks are typically assumed to be a sign of multiple belts, but only a few cases have been confirmed via high resolution observations. We derive the properties of a sample of two-temperature disks, and explore whether this emission can arise from dust in a single narrow belt. While some two-temperature disks arise from single belts, it is probable that most have multiple spatial components. These disks are plausibly similar to the outer Solar System's configuration of Asteroid and Edgeworth-Kuiper belts separated by giant planets. Alternatively, the inner component could arise from inward scattering of material from the outer belt, again due to intervening planets. For either scenario, the ratio of warm/cool component temperatures is indicative of the scale of outer planetary systems, which typically span a factor of about ten in radius.

The Long View of Planetary Systems

2018 ◽  
Author(s):  
Karel Schrijver
Keyword(s):  
Solar System ◽  
Milky Way ◽  
Planetary Systems ◽  
Giant Planets ◽  
Milky Way Galaxy ◽  
Population Statistics ◽  
The Past ◽  
General Terms ◽  
The Galaxy ◽  
The Universe

How many planetary systems formed before our’s did, and how many will form after? How old is the average exoplanet in the Galaxy? When did the earliest planets start forming? How different are the ages of terrestrial and giant planets? And, ultimately, what will the fate be of our Solar System, of the Milky Way Galaxy, and of the Universe around us? We cannot know the fate of individual exoplanets with great certainty, but based on population statistics this chapter sketches the past, present, and future of exoworlds and of our Earth in general terms.

scholarly journals Predicting the stellar and non-equilibrium dust emission spectra of high-resolution simulated galaxies with dart-ray

2015 ◽  
Vol 449 (1) ◽  
pp. 243-267 ◽  
Author(s):  
Giovanni Natale ◽  
Cristina C. Popescu ◽  
Richard. J. Tuffs ◽  
Victor P. Debattista ◽  
Jörg Fischera ◽  
...  
Keyword(s):  
High Resolution ◽  
Dust Emission ◽  
Emission Spectra ◽  
Non Equilibrium

scholarly journals The Complete Census of 70 μm–Bright Debris Disks within “The Formation and Evolution of Planetary Systems”SpitzerLegacy Survey of Sun‐like Stars

2008 ◽  
Vol 677 (1) ◽  
pp. 630-656 ◽  
Author(s):  
Lynne A. Hillenbrand ◽  
John M. Carpenter ◽  
Jinyoung Serena Kim ◽  
Michael R. Meyer ◽  
Dana E. Backman ◽  
...  
Keyword(s):  
Planetary Systems ◽  
Debris Disks ◽  
Formation And Evolution

scholarly journals On the survival of resonant and non-resonant planetary systems in star clusters

2020 ◽  
Vol 497 (2) ◽  
pp. 1807-1825
Author(s):  
Katja Stock ◽  
Maxwell X Cai ◽  
Rainer Spurzem ◽  
M B N Kouwenhoven ◽  
Simon Portegies Zwart
Keyword(s):  
Solar System ◽  
Star Clusters ◽  
Planetary Systems ◽  
Dynamical Evolution ◽  
Giant Planets ◽  
Mean Motion Resonances ◽  
Orbital Parameters ◽  
Eccentric Orbits ◽  
The Individual ◽  
Exoplanet Systems

ABSTRACT Despite the discovery of thousands of exoplanets in recent years, the number of known exoplanets in star clusters remains tiny. This may be a consequence of close stellar encounters perturbing the dynamical evolution of planetary systems in these clusters. Here, we present the results from direct N-body simulations of multiplanetary systems embedded in star clusters containing N = 8k, 16k, 32k, and 64k stars. The planetary systems, which consist of the four Solar system giant planets Jupiter, Saturn, Uranus, and Neptune, are initialized in different orbital configurations, to study the effect of the system architecture on the dynamical evolution of the entire planetary system, and on the escape rate of the individual planets. We find that the current orbital parameters of the Solar system giants (with initially circular orbits, as well as with present-day eccentricities) and a slightly more compact configuration, have a high resilience against stellar perturbations. A configuration with initial mean-motion resonances of 3:2, 3:2, and 5:4 between the planets, which is inspired by the Nice model, and for which the two outermost planets are usually ejected within the first 105 yr, is in many cases stabilized due to the removal of the resonances by external stellar perturbation and by the rapid ejection of at least one planet. Assigning all planets the same mass of 1 MJup almost equalizes the survival fractions. Our simulations reproduce the broad diversity amongst observed exoplanet systems. We find not only many very wide and/or eccentric orbits, but also a significant number of (stable) retrograde orbits.

scholarly journals A FULL-SKY, HIGH-RESOLUTION ATLAS OF GALACTIC 12 μm DUST EMISSION WITHWISE

2013 ◽  
Vol 781 (1) ◽  
pp. 5 ◽  
Author(s):  
Aaron M. Meisner ◽  
Douglas P. Finkbeiner
Keyword(s):  
High Resolution ◽  
Dust Emission

scholarly journals Planet forming disks, debris disks and the Solar System

2019 ◽  
Vol 15 (S350) ◽  
pp. 207-215
Author(s):  
Inga Kamp
Keyword(s):  
Chemical Composition ◽  
Solar System ◽  
Planetary Systems ◽  
Theoretical Work ◽  
Structure Evolution ◽  
Debris Disks ◽  
Physical Processes ◽  
Disk Structure ◽  
Open Questions ◽  
Evolution Modeling

AbstractVLT instruments and ALMA with their high spatial resolution have revolutionized in the past five years our view and understanding of how disks turn into planetary systems. This talk will briefly outline our current understanding of the physical processes occurring and chemical composition evolving as these disks turn into debris disks and eventually planetary systems like our own solar system. I will especially focus on the synergy between disk structure/evolution modeling and astrochemical laboratory/theoretical work to highlight the most recent advances, and open questions such as (1) how much of the chemical composition in disks is inherited from molecular clouds, (2) the relevance of snowlines for planet formation, and (3) what is the origin of the gas in debris disks and what can we learn from it. For each of the three, I will outline briefly how the combination of theory/lab astrochemistry, astrophysical models and observations are required to advance our understanding.

scholarly journals Trojans in Exosystems with Two Massive Planets

2012 ◽  
Vol 8 (S293) ◽  
pp. 152-158 ◽  
Author(s):  
Rudolf Dvorak ◽  
Li-Yong Zhou ◽  
Helmut Baudisch
Keyword(s):  
Numerical Integration ◽  
Equilibrium Points ◽  
Planetary Systems ◽  
Central Star ◽  
Giant Planets ◽  
Dynamical Model ◽  
Outer Planet ◽  
Mass Ratio ◽  
Wide Range ◽  
Mass Ratios

AbstractWe take as dynamical model for extrasolar planetary systems a central star like our Sun and two giant planets m1 and m2 like Jupiter and Saturn. We change the mass ratio μ=m2/m1 of the two large planets for a wide range of 1/16 < μ < 16. We also change the ratio between the initial semi-major axes (ν=a2/a1) in the range of 1.2 < ν < 3 to model the different architecture of extrasolar planetary systems hosting two giant planets. The results for possible Trojans (Trojan planets) in the equilateral equilibrium points of the inner planet m1 and the outer planet m2 were derived with the aid of numerical integration. It turned out that in many configurations – depending on the mass ratios μ and the semi-major axes ratio ν – giant planets may host Trojans.

TWO-TEMPERATURE NON-EQUILIBRIUM ISING MODELS

1996 ◽  
Vol 07 (03) ◽  
pp. 389-399 ◽  
Author(s):  
P. TAMAYO ◽  
R. GUPTA ◽  
F. J. ALEXANDER
Keyword(s):  
Ising Model ◽  
Computational Study ◽  
Heat Bath ◽  
Universality Class ◽  
Ising Models ◽  
Local Competition ◽  
Equilibrium Dynamics ◽  
Different Temperatures ◽  
Two Temperature ◽  
Non Equilibrium

We present results from a computational study of a class of 2D two-temperature non-equilibrium Ising models. In these systems the dynamics is a local competition of two equilibrium dynamics at different temperatures. We analyzed non-equilibrium versions of Metropolis, heat bath/Glauber and Swendsen-Wang dynamics and found strong evidence that some of these dynamics have the same critical exponents and belong to the same universality class as the equilibrium 2D Ising model.

scholarly journals ALMA observations of the “fresh” carbon-rich AGB star TX Piscium

2019 ◽  
Vol 621 ◽  
pp. A50 ◽  
Author(s):  
M. Brunner ◽  
M. Mecina ◽  
M. Maercker ◽  
E. A. Dorfi ◽  
F. Kerschbaum ◽  
...  
Keyword(s):  
High Resolution ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Dust Emission ◽  
Asymptotic Giant Branch ◽  
Circumstellar Envelope ◽  
Spherically Symmetric ◽  
Stellar Rotation ◽  
Brown Dwarf ◽  
Rotation Rates

Aims. The carbon-rich asymptotic giant branch (AGB) star TX Piscium (TX Psc) has been observed multiple times during multiple epochs and at different wavelengths and resolutions, showing a complex molecular CO line profile and a ring-like structure in thermal dust emission. We investigate the molecular counterpart in high resolution, aiming to resolve the ring-like structure and identify its origin. Methods. Atacama Large Millimeter/submillimeter Array (ALMA) observations have been carried out to map the circumstellar envelope (CSE) of TX Psc in CO(2–1) emission and investigate the counterpart to the ring-like dust structure. Results. We report the detection of a thin, irregular, and elliptical detached molecular shell around TX Psc, which coincides with the dust emission. This is the first discovery of a non-spherically symmetric detached shell, raising questions about the shaping of detached shells. Conclusions. We investigate possible shaping mechanisms for elliptical detached shells and find that in the case of TX Psc, stellar rotation of 2 km s−1 can lead to a non-uniform mass-loss rate and velocity distribution from stellar pole to equator, recreating the elliptical CSE. We discuss the possible scenarios for increased stellar momentum, enabling the rotation rates needed to reproduce the ellipticity of our observations, and come to the conclusion that momentum transfer of an orbiting object with the mass of a brown dwarf would be sufficient.

scholarly journals Growth and interaction of planets

2004 ◽  
Vol 202 ◽  
pp. 149-158 ◽  
Author(s):  
Pawel Artymowicz
Keyword(s):  
Planetary Systems ◽  
Giant Planets ◽  
The Sun ◽  
Orbital Structure ◽  
Origin And Evolution ◽  
Elliptic Orbits ◽  
Observational Techniques

We discuss theories of origin and evolution of the newly discovered extrasolar planetary systems. As these systems failed to fulfill prior expectations concerning their orbital structure, we are challenged to extend and/or revise many preexisting theories. Important extensions include migration of bodies in disks and planetary eccentricity pumping by planet-planet interaction and primordial disk-planet interaction. Progress in observational techniques will allow us to find which of these two types of interaction is responsible for the observed variety of orbits and masses of planets. New insights into the formation of giant planets in our system can be obtained by asking why Jupiter and Saturn are not larger, closer to the sun and/or do not follow noticeably elliptic orbits.

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