Apparent Disk-mass Reduction and Planetisimal Formation in GravitationallyUnstable Disks in Class 0/I Young Stellar Objects

Tsukamoto, Yusuke; Okuzumi, Satoshi; Kataoka, Akimasa

doi:10.3847/1538-4357/aa6081

Cited by 52 publications

(58 citation statements)

References 130 publications

(231 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We find that the radial drift becomes appreciable when their drift timescale t drift = r/|v r | becomes shorter than 30 times the growth timescale t grow = m d /(dm d /dt), in agreement with the situation for dust evolution in protoplanetary disks (Okuzumi et al 2012;Tsukamoto et al 2017). Foṙ M d /Ṁ g = 1, we find that the particles stop drifting and grow to kilometer-sized satellitesimals at r ∼ 10 R J .…”

Section: Fiducial Calculationssupporting

confidence: 84%

Satellitesimal Formation via Collisional Dust Growth in Steady Circumplanetary Disks

Shibaike

Okuzumi

Sasaki

et al. 2017

ApJ

Self Cite

View full text Add to dashboard Cite

The icy satellites around Jupiter are considered to have formed in a circumplanetary disk. While previous models focused on the formation of satellites starting from satellitesimals, the question of how satellitesimals form from smaller dust particles has not been addressed so far. In this work, we study the possibility that satellitesimals form in situ in a circumplanetary disk. We calculate the radial distribution of the surface density and representative size of icy dust particles that grow by colliding with each other and drift toward the central planet in a steady circumplanetary disk with a continuous supply of gas and dust from the parent protoplanetary disk. The radial drift barrier is overcome if the ratio of the dust to gas accretion rates onto the circumplanetary disk,Ṁ d /Ṁ g , is high and the strength of turbulence, α, is not too low. The collision velocity is lower than the critical velocity of fragmentation when α is low. Taken together, we find that the conditions for satellitesimal formation via dust coagulation are given byṀ d /Ṁ g ≥ 1 and 10 −4 ≤ α < 10 −2 . The former condition is generally difficult to achieve, suggesting that the in-situ satellitesimal formation via particle sticking is viable only under an extreme condition. We also show that neither satellitesimal formation via the collisional growth of porous aggregates nor via streaming instability is viable as long asṀ d /Ṁ g is low.

show abstract

Section: Fiducial Calculationssupporting

confidence: 84%

Satellitesimal Formation via Collisional Dust Growth in Steady Circumplanetary Disks

Shibaike

Okuzumi

Sasaki

et al. 2017

ApJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…The growth time of the aggregate during the hit-and-stick phase can be estimated as in Tsukamoto et al (2017):…”

Section: The Growth Time and Destruction By Collisionsmentioning

confidence: 99%

Planet Formation around Supermassive Black Holes in the Active Galactic Nuclei

Wada

Tsukamoto

Kokubo

2019

ApJ

View full text Add to dashboard Cite

As a natural consequence of the elementary processes of dust growth, we discovered that a new class of planets can be formed around supermassive black holes (SMBHs). We investigated a growth path from sub-micron sized icy dust monomers to Earthsized bodies outside the "snow line", located several parsecs from SMBHs in low luminosity active galactic nuclei (AGNs). In contrast to protoplanetary disks, the "radial drift barrier" does not prevent the formation of planetesimals. In the early phase of the evolution, low collision velocity between dust particles promotes sticking; therefore, the internal density of the dust aggregates decreases with growth. When the porous aggregate's size reaches 0.1-1 cm, the collisional compression becomes effective, and the decrease in internal density stops. Once 10-100 m sized aggregates are formed, they are decoupled from gas turbulence, and the aggregate layer becomes gravitationally unstable, leading to the formation of planets by the fragmentation of the layer, with ten times the mass of the earth. The growth time scale depends on the turbulent strength of the circumnuclear disk and the black hole mass M BH , and it is comparable to the AGN's lifetime (∼ 10 8 yr) for low mass (M BH ∼ 10 6 M ) SMBHs.

show abstract

“…the density and temperature profiles) of such a massive disk is very different from the conventional disk models like MMSN. In such massive disks, it is possible that the dust grains are already grown up significantly since the gas and dust densities are high (Tsukamoto et al 2017). Therefore, the planet formation can be already started even in the early phase of star formation where the star and disk are still growing by accretion.…”

Section: Implications For Planet Formationmentioning

confidence: 99%