The Pyrenean orogen: pre-, syn-, and post-collisional evolution

AbstractIn this work, we study the impactor flux on Pluto and Charon due to the collisional evolution of Plutinos.To do this, we develop a statistical code that includes catastrophic collisions and cratering events, and takes into account the stability and instability zones of the 3:2 mean motion resonance with Neptune. Our results suggest that if 1 Pluto-sized object is in this resonance, the flux of D = 2 km Plutinos on Pluto is ~4–24 percent of the flux of D = 2 km Kuiper Belt projectiles on Pluto. However, with 5 Pluto-sized objects in the resonance, the contribution of the Plutino population to the impactor flux on Pluto may be comparable to that of the Kuiper Belt. As for Charon, if 1 Pluto-sized object is in the 3:2 resonance, the flux of D = 2 km Plutinos is ~10–63 percent of the flux of D = 2 km impactors coming from the Kuiper Belt. However, with 5 Pluto-sized objects, the Plutino population may be a primary source of the impactor flux on Charon. We conclude that it is necessary to specify the Plutino size distribution and the number of Pluto-sized objects in the 3:2 Neptune resonance in order to determine if the Plutino population is a primary source of impactors on the Pluto-Charon system.

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Direct imaging of irregular satellite discs in scattered light

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa195 ◽

2020 ◽

Vol 492 (4) ◽

pp. 5709-5720

Author(s):

Loic Nassif-Lachapelle ◽

Daniel Tamayo

Keyword(s):

Near Infrared ◽

Thermal Emission ◽

Scattered Light ◽

Semimajor Axis ◽

Detection Methods ◽

Direct Imaging ◽

Irregular Satellites ◽

Long Period ◽

Wide Range ◽

Collisional Evolution

ABSTRACT Direct imaging surveys have found that long-period super-Jupiters are rare. By contrast, recent modelling of the widespread gaps in protoplanetary discs revealed by Atacama Large Millimetre Array suggests an abundant population of smaller Neptune to Jupiter-mass planets at large separations. The thermal emission from such lower-mass planets is negligible at optical and near-infrared wavelengths, leaving only their weak signals in reflected light. Planets do not scatter enough light at these large orbital distances, but there is a natural way to enhance their reflecting area. Each of the four giant planets in our Solar system hosts swarms of dozens of irregular satellites, gravitationally captured planetesimals that fill their host planets’ spheres of gravitational influence. What we see of them today are the leftovers of an intense collisional evolution. At early times, they would have generated bright circumplanetary debris discs. We investigate the properties and detectability of such irregular satellite discs (ISDs) following models for their collisional evolution from Kennedy & Wyatt (2011). We find that the scattered light signals from such ISDs would peak in the 10–100 au semimajor axis range implied by ALMA, and can render planets detectable over a wide range of parameters with upcoming high-contrast instrumentation. We argue that future instruments with wide fields of view could simultaneously characterize the atmospheres of known close-in planets, and reveal the population of long-period Neptune–Jupiter mass exoplanets inaccessible to other detection methods. This provides a complementary and compelling science case that would elucidate the early lives of planetary systems.

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Long‐Term Collisional Evolution of Debris Disks

The Astrophysical Journal ◽

10.1086/524840 ◽

2008 ◽

Vol 673 (2) ◽

pp. 1123-1137 ◽

Cited By ~ 128

Author(s):

Torsten Lohne ◽

Alexander V. Krivov ◽

Jens Rodmann

Keyword(s):

Debris Disks ◽

Collisional Evolution

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New multi-part collisional model of the main belt: the contribution to near-Earth asteroids

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037458 ◽

2020 ◽

Vol 639 ◽

pp. A9

Author(s):

P. S. Zain ◽

G. C. de Elía ◽

R. P. Di Sisto

Keyword(s):

Significant Contribution ◽

Asteroid Belt ◽

Size Distributions ◽

Main Belt ◽

Yarkovsky Effect ◽

Source Regions ◽

Main Asteroid Belt ◽

Near Earth Asteroids ◽

Asteroid Families ◽

Collisional Evolution

Aims. We developed a six-part collisional evolution model of the main asteroid belt (MB) and used it to study the contribution of the different regions of the MB to the near-Earth asteroids (NEAs). Methods. We built a statistical code called ACDC that simulates the collisional evolution of the MB split into six regions (namely Inner, Middle, Pristine, Outer, Cybele and High-Inclination belts) according to the positions of the major resonances present there (ν6, 3:1J, 5:2J, 7:3J and 2:1J). We consider the Yarkovsky effect and the mentioned resonances as the main mechanism that removes asteroids from the different regions of the MB and delivers them to the NEA region. We calculated the evolution of the NEAs coming from the different source regions by considering the bodies delivered by the resonances and mean dynamical timescales in the NEA population. Results. Our model is in agreement with the major observational constraints associated with the MB, such as the size distributions of the different regions of the MB and the number of large asteroid families. It is also able to reproduce the observed NEAs with H < 16 and agrees with recent estimations for H < 20, but deviates for smaller sizes. We find that most sources make a significant contribution to the NEAs; however the Inner and Middle belts stand out as the most important source of NEAs followed by the Outer belt. The contributions of the Pristine and Cybele regions are minor. The High-Inclination belt is the source of only a fraction of the actual observed NEAs with high inclination, as there are dynamical processes in that region that enable asteroids to increase and decrease their inclinations.

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COLLISIONAL EVOLUTION OF ULTRA-WIDE TRANS-NEPTUNIAN BINARIES

The Astrophysical Journal ◽

10.1088/0004-637x/744/2/139 ◽

2011 ◽

Vol 744 (2) ◽

pp. 139 ◽

Cited By ~ 25

Author(s):

Alex H. Parker ◽

J. J. Kavelaars

Keyword(s):

Collisional Evolution

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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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