Are inner disc misalignments common? ALMA reveals an isotropic outer disc inclination distribution for young dipper stars

Ansdell, Megan; Gaidos, Eric; Hedges, Christina; Tazzari, Marco; Kraus, Adam L.; Wyatt, M. C.; Kennedy, Grant M.; Williams, Jonathan P.; Mann, Andrew W.; Angelo, Isabel; Duchêne, Gaspard; Mamajek, Eric E.; Carpenter, John M.; Esplin, T. L.; Rizzuto, Aaron C.

doi:10.1093/mnras/stz3361

Cited by 59 publications

(65 citation statements)

References 115 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dippers with nearly faceon outer disks have been found before (e.g., Ansdell et al 2016b;Scaringi et al 2016). In particular, Ansdell et al (2020) found the disk inclination distribution to be consistent with isotropic. The possible explanations they proposed include dust clouds driven by disk winds (which can determine dips in systems with inclinations as low as ∼30 • ), or misalignments between inner and outer disk (which might be caused by a substellar or planetary companion).…”

Section: Discussionsupporting

confidence: 52%

ISO-ChaI 52: a weakly accreting young stellar object with a dipper light curve

Frasca

Manara

Alcalá

et al. 2020

A&A

View full text Add to dashboard Cite

We report the discovery of periodic dips in the multiband light curve of ISO-ChaI 52, a young stellar object in the Chamaeleon I dark cloud. This is one of the peculiar objects that display very low or negligible accretion in their UV continuum and spectral lines, although they present a remarkable infrared excess emission characteristic of optically thick circumstellar disks. We have analyzed a spectrum obtained at the Very Large Telescope with the X-shooter spectrograph with the tool ROTFIT to determine the stellar parameters. The latter, along with photometry from our campaign with the Rapid Eye Mount telescope and from the literature, have allowed us to model the spectral energy distribution and to estimate the size and temperature of the inner and outer disk. Based on the rotational period of the star-disk system of 3.45 days, we estimate a disk inclination of 36°. The depth of the dips in different bands has been used to gain information about the occulting material. A single extinction law is not able to fit the observed behavior, while a two-component model of a disk warp composed of a dense region with a gray extinction and an upper layer with an extinction as in the interstellar medium provides a better fit to the data.

show abstract

Section: Discussionsupporting

confidence: 52%

ISO-ChaI 52: a weakly accreting young stellar object with a dipper light curve

Frasca

Manara

Alcalá

et al. 2020

A&A

View full text Add to dashboard Cite

show abstract

“…Dippers instead are very young, PMS stars in almost all cases with active accretion from a primordial disk and strong infrared (IR) excesses; their flux dips are generally believed to arise from dust in the primordial disk itself or possibly from dust blobs in transit from the disk toward the star. (Also see Ansdell et al 2020. )…”

Section: A Brief Discussion Of Nomenclaturementioning

confidence: 97%

Even More Rapidly Rotating Pre-main-sequence M Dwarfs with Highly Structured Light Curves: An Initial Survey in the Lower Centaurus-Crux and Upper Centaurus-Lupus Associations

Stauffer

Rebull

Jardine

et al. 2021

View full text Add to dashboard Cite

Using K2, we recently discovered a new type of periodic photometric variability while analyzing the light curves of members of Upper Sco. The 23 exemplars of this new variability type are all mid-M dwarfs, with short rotation periods. Their phased light curves have one or more broad flux dips or multiple arcuate structures which are not explicable by photospheric spots or eclipses by solid bodies. Now, using Transiting Exoplanet Survey Satellite data, we have searched for this type of variability in the other major sections of Sco-Cen, Upper Centaurus-Lupus (UCL), and Lower Centaurus-Crux (LCC). We identify 28 stars with the same light curve morphologies. We find no obvious difference between the Upper Sco and the UCL/LCC representatives of this class in terms of their light curve morphologies, periods, or variability amplitudes. The physical mechanism behind this variability is unknown, but as a possible clue we show that the rapidly rotating mid-M dwarfs in UCL/LCC have slightly different colors from the slowly rotating M dwarfs-they either have a blue excess (hot spots?) or a red excess (warm dust?). One of the newly identified stars (TIC242407571) has a very striking light curve morphology. At about every 0.05 in phase are features that resemble icicles. The icicles arise because there is a second periodic system whose main feature is a broad flux dip. Using a toy model, we show that the observed light curve morphology results only if the ratio of the two periods and the flux-dip width are carefully arranged.

show abstract

“…In this paper, we present new ALMA Band 6 220 GHz continuum observations of LkCa 15 and 2MASS J16100501-2132318 (EM*StHA 123, EPIC 204630363, hereafter J1610) at unprecedented angular resolution (∼40 × 60 mas, i.e., ∼7.5 and 6 au in radius for LkCa 15 and J1610, respectively). Both objects are classical T Tauri stars hosting transition disks with resolved cavities (Piétu et al 2006;Ansdell et al 2020). Interestingly they are also classified as dippers, based on the short term variability seen in their optical light curves (Ansdell et al 2016;Rodriguez et al 2017;Alencar et al 2018).…”

Section: Introductionmentioning

confidence: 99%

Annular substructures in the transition disks around LkCa 15 and J1610

Facchini

Benisty

Bae

et al. 2020

A&A

View full text Add to dashboard Cite

We present high-resolution millimeter continuum ALMA observations of the disks around the T Tauri stars LkCa 15 and 2MASS J16100501-2132318 (hereafter, J1610). These transition disks host dust-depleted inner regions, which have possibly been carved by massive planets, and they are of prime interest to the study of the imprints of planet-disk interactions. While at moderate angular resolution, they appear as a broad ring surrounding a cavity, the continuum emission resolves into multiple rings at a resolution of ~60 × 40 mas (~7.5 au for LkCa 15, ~6 au for J1610) and ~7 μJy beam−1 rms at 1.3 mm. In addition to a broad extended component, LkCa 15 and J1610 host three and two narrow rings, respectively, with two bright rings in LkCa 15 being radially resolved. LkCa 15 possibly hosts another faint ring close to the outer edge of the mm emission. The rings look marginally optically thick, with peak optical depths of ~0.5 (neglecting scattering), in agreement with high angular resolution observations of full disks. We performed hydrodynamical simulations with an embedded, sub-Jovian-mass planet and show that the observed multi-ringed substructure can be qualitatively explained as the outcome of the planet-disk interaction. We note, however, that the choice of the disk cooling timescale alone can significantly impact the resulting gas and dust distributions around the planet, leading to different numbers of rings and gaps and different spacings between them. We propose that the massive outer disk regions of transition disks are favorable places for planetesimals, and possibly second-generation planet formation of objects with a lower mass than the planets carving the inner cavity (typically few MJup), and that the annular substructures observed in LkCa 15 and J1610 may be indicative of planetary core formation within dust-rich pressure traps. Current observations are compatible with other mechanisms contributing to the origin of the observed substructures, in particular with regard to narrow rings generated (or facilitated) at the edge of the CO and N2 snowlines.

show abstract

Are inner disc misalignments common? ALMA reveals an isotropic outer disc inclination distribution for young dipper stars

Cited by 59 publications

References 115 publications

ISO-ChaI 52: a weakly accreting young stellar object with a dipper light curve

ISO-ChaI 52: a weakly accreting young stellar object with a dipper light curve

Even More Rapidly Rotating Pre-main-sequence M Dwarfs with Highly Structured Light Curves: An Initial Survey in the Lower Centaurus-Crux and Upper Centaurus-Lupus Associations

Annular substructures in the transition disks around LkCa 15 and J1610

Contact Info

Product

Resources

About