On the Dust Signatures Induced by Eccentric Super-Earths in Protoplanetary Disks

Li, Yaping; Li, Hui; Li, Shengtai; Lin, D. N. C.

doi:10.3847/1538-4357/ab4bc8

Cited by 19 publications

(13 citation statements)

References 74 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To avoid uncertainties, we start averaging from 500 orbits, and the result of τ e in q = 1e − 4 cases are plotted in Fig 7 for the fiducial as well as additional simulations. We find that for q = 10 −4 , the gas damping timescale τ e for e = 0.1, h 0 = 0.05 converges to a few hundred orbits without external forcing, in agreement with the findings of Cresswell et al (2007); Bitsch & Kley (2010); Li et al (2019a), equivalent to a few to ten thousand years in physical units for a p = 10 − 30au. These are relatively small fractions of the disk lifetime.…”

Section: Eccentricity Excitation and Dampingsupporting

confidence: 88%

“…While the validity of a universal power-law index of β remains to be further examined, and consideration a few (20-30) samples may be misled by intrinsic observational errors due to beam smear-ing, we draw attention to another hitherto neglected facet that may introduce much uncertainty in these inferences: the embedded planets' eccentricity, a possible result of planet-disk interactions (Papaloizou et al 2001;Goldreich & Sari 2003;Kley & Dirksen 2006;Li et al 2021) when there is a cavity in the gas (Debras et al 2021) or interaction between multiple planet embryos (Zhang et al 2014). The Hill radius scaling is inferred from simulations of planets on circular orbits, while planets with eccentric orbits might extend the characteristic width of the gap when their radial excursion is larger than their Hill radius (Li et al 2019a). In particular, planets with masses comparable to Neptune and non-negligible eccentricities might be mistakenly identified as Saturn-mass planets on circular orbits if their mass is extrapolated from the conventional approaches.…”

Section: Introductionmentioning

confidence: 98%

“…Another motivation to investigate eccentric planets in ALMA disks is that they are known to induce shallower gaps than circular cases (e.g. Duffell & Chiang 2015;Li et al 2019a), which disfavors the theoretical prediction on the excitation of Rossby Wave Instability (RWI) and the generation of vortices (Lovelace et al 1999;Li et al 2000Li et al , 2001Li et al , 2005Li et al , 2020. This effect would reconcile the tension between generally-inferred low viscosity in T Tauri disks and the lack of observed asymmetries (van der Marel et al 2021;Hammer et al 2021).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Wide Dust Gaps in Protoplanetary Disks Induced by Eccentric Planets: A Mass-Eccentricity Degeneracy

Chen,

Wang,

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

The tidal perturbation of embedded protoplanets on their natal disks has been widely attributed to be the cause of gap-ring structures in sub-mm images of protoplanetary disks around T Tauri stars. Numerical simulations of this process have been used to propose scalings of characteristic dust gap width/gap-ring distance with respect to planet mass. Applying such scalings to analyze observed gap samples yields a continuous mass distribution for a rich population of hypothetical planets in the range of several Earth to Jupiter masses. In contrast, the conventional core-accretion scenario of planet formation predicts a bi-modal mass function due to 1) the onset of runaway gas accretion above ∼20 Earth masses and 2) suppression of accretion induced by gap opening. Here we examine the dust disk response to the tidal perturbation of eccentric planets as a possible resolution of this paradox. Based on simulated gas and dust distributions, we show the gap-ring separation of Neptune-mass planets with small eccentricities might become comparable to that induced by Saturn-mass planets on circular orbits. This degeneracy may obliterate the discrepancy between the theoretical bi-modal mass distribution and the observed continuous gap width distribution. Despite damping due to planet-disk interaction, modest eccentricity may be sustained either in the outer regions of relatively thick disks or through resonant excitation among multiple super Earths. Moreover, the ring-like dust distribution induced by planets with small eccentricities is axisymmetric even in low viscosity environments, consistent with the paucity of vortices in ALMA images.

show abstract

Section: Eccentricity Excitation and Dampingsupporting

confidence: 88%

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Wide Dust Gaps in Protoplanetary Disks Induced by Eccentric Planets: A Mass-Eccentricity Degeneracy

Chen,

Wang,

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…Giant planets of several Jupiter masses interacting with a gaseous disk are expected to have their eccentricities quickly damped to below the disk aspect ratio, here about 20% (Dunhill et al 2013;Duffell & Chiang 2015). Simulations have also shown that density waves excited by planets with e0.2 develop wiggles and bifurcations, as the waves launched at different phases interact (Li et al 2019;Muley et al 2019), which provide poor fits to the arms around MWC758. A modest eccentricity introduces an uncertainty in the inferred planet location comparable to the uncertainty from pattern speed measurements-for example, e=0.2 translates to a range of possible companion locations from 155 to 190au.…”

Section: Eccentric Drivermentioning

confidence: 99%

Dynamical Evidence of a Spiral Arm–driving Planet in the MWC 758 Protoplanetary Disk

Ren

Dong

Holstein

et al. 2020

ApJL

View full text Add to dashboard Cite

More than a dozen young stars host spiral arms in their surrounding protoplanetary disks. The excitation mechanisms of such arms are under debate. The two leading hypotheses-companion-disk interaction and gravitational instability (GI)-predict distinct motion for spirals. By imaging the MWC758 spiral arm system at two epochs spanning ∼5 yr using the SPHERE instrument on the Very Large Telescope, we test the two hypotheses for the first time. We find that the pattern speeds of the spirals are not consistent with the GI origin. Our measurements further evince the existence of a faint "missing planet" driving the disk arms. The average spiral pattern speed is 0°.22±0°.03 yr −1 , pointing to a driver at-+ 172 14 18 au around a 1.9 M ☉ central star if it is on a circular orbit. In addition, we witness time-varying shadowing effects on a global scale that are likely originating from an inner disk.

show abstract

“…Calcino et al (2020) use an eccentric perturber to reproduce several features of the spirals in MWC 758. The eccentric perturber has also been proposed to explain observed gap structures (Muley et al 2019;Li et al 2019;Chen et al 2021). Theoretical works also suggest that planets can gain eccentricity by interacting with protoplanetary discs (Goldreich & Sari 2003;Teyssandier & Ogilvie 2017;Ragusa et al 2018).…”

Section: Introductionmentioning

confidence: 98%

A Simple Time-Dependent Method for Calculating Spirals: Applications to Eccentric Planets in Protoplanetary discs

Zhu,

Zhang

2021

Preprint

View full text Add to dashboard Cite

Spirals in protoplanetary discs have been used to locate the potential planet in discs. Since only the spiral shape from a circularly orbiting perturber is known, most previous works assume that the planet is in a circular orbit. We develop a simple semi-analytical method to calculate the shape of the spirals launched by an eccentric planet. We assume that the planet emits wavelets during its orbit, and the wave fronts of these propagating wavelets form the spirals. The resulting spiral shape from this simple method agrees with numerical simulations exceptionally well. The spirals excited by an eccentric planet can detach from the planet, bifurcate, or even cross each other, which are all reproduced by this simple method. The spiral's bifurcation point corresponds to the wavelet that is emitted when the planet's radial speed reaches the disc's sound speed. Multiple spirals can be excited by an eccentric planet (more than 5 spirals when e 0.2). The pitch angle and pattern speed are different between different spirals and can vary significantly across one spiral. The spiral wakes launched by high-mass eccentric planets steepen to spiral shocks and the crossing of spiral shocks leads to distorted or broken spirals. With the same mass, a more eccentric planet launches weaker spirals and induces a shallower gap over a long period of time. The observed unusually large/small pitch angles of some spirals, the irregular multiple spirals, and the different pattern speeds between different spirals may suggest the existence of eccentric perturbers in protoplanetary discs.

show abstract

On the Dust Signatures Induced by Eccentric Super-Earths in Protoplanetary Disks

Cited by 19 publications

References 74 publications

Wide Dust Gaps in Protoplanetary Disks Induced by Eccentric Planets: A Mass-Eccentricity Degeneracy

Wide Dust Gaps in Protoplanetary Disks Induced by Eccentric Planets: A Mass-Eccentricity Degeneracy

Dynamical Evidence of a Spiral Arm–driving Planet in the MWC 758 Protoplanetary Disk

A Simple Time-Dependent Method for Calculating Spirals: Applications to Eccentric Planets in Protoplanetary discs

Contact Info

Product

Resources

About