An ALMA Survey of CO Isotopologue Emission from Protoplanetary Disks in Chamaeleon I

Long, Feng; Herczeg, Gregory J.; Pascucci, Ilaria; Drabek-Maunder, E.; Mohanty, Subhanjoy; Testi, L.; Apai, Dániel; Hendler, Nathanial P.; Henning, Thomas; Manara, C. F.; Mulders, Gijs D.

doi:10.3847/1538-4357/aa78fc

Cited by 137 publications

(151 citation statements)

References 116 publications

Supporting

Mentioning

142

Contrasting

Order By: Relevance

“…However, very recent work by Long et al (2017) estimate the gas mass around ESO-Hα 569 from ALMA 13 CO line emission and find only~M 1.3 Jup of gas mass in the disk, although optical depth effects and details of the CO freeze-out are likely to introduce major sources of uncertainty. Combined with our own dust mass estimate, this gives an uncharacteristically low gas-to-dust ratio of only ∼2.…”

Section: Surface Density Exponentmentioning

confidence: 99%

Hubble Space Telescope Scattered-light Imaging and Modeling of the Edge-on Protoplanetary Disk ESO-Hα 569

Wolff

Perrin

Stapelfeldt

et al. 2017

ApJ

View full text Add to dashboard Cite

We present new Hubble Space Telescope (HST) Advanced Camera for Surveys observations and detailed models for a recently discovered edge-on protoplanetary disk around ESO-Hα569 (a low-mass T Tauri star in the Cha I star-forming region). Using radiative transfer models, we probe the distribution of the grains and overall shape of the disk (inclination, scale height, dust mass, flaring exponent, and surface/volume density exponent) by model fitting to multiwavelength (F606W and F814W) HST observations together with a literature-compiled spectral energy distribution. A new tool set was developed for finding optimal fits of MCFOST radiative transfer models using the MCMC code emcee to efficiently explore the high-dimensional parameter space. It is able to selfconsistently and simultaneously fit a wide variety of observables in order to place constraints on the physical properties of a given disk, while also rigorously assessing the uncertainties in those derived properties. We confirm that ESO-Hα569 is an optically thick nearly edge-on protoplanetary disk. The shape of the disk is well-described by a flared disk model with an exponentially tapered outer edge, consistent with models previously advocated on theoretical grounds and supported by millimeter interferometry. The scattered-light images and spectral energy distribution are best fit by an unusually high total disk mass (gas+dust assuming a ratio of 100:1) with a disk-tostar mass ratio of 0.16.

show abstract

Section: Surface Density Exponentmentioning

confidence: 99%

Hubble Space Telescope Scattered-light Imaging and Modeling of the Edge-on Protoplanetary Disk ESO-Hα 569

Wolff

Perrin

Stapelfeldt

et al. 2017

ApJ

View full text Add to dashboard Cite

show abstract

“…In this case, CO or gas depletion may be even more severe than currently estimated, although large line optical depths may also contribute to underestimates of the amounts of CO or gas (e.g. Ansdell et al 2016;Barenfeld et al 2016;Long et al 2017). Highresolution, multi-band ALMA surveys of protoplanetary disks can determine whether other disks have continuum emission and spectral index profiles similar to that of TW Hya.…”

Section: Comparison To Other Sourcesmentioning

confidence: 99%

“…Barenfeld et al 2016;Long et al 2017;Miotello et al 2017). As the nearest disk, TW Hya may be the most important test case for breaking the degeneracy.…”

Section: Comparison To Other Sourcesmentioning

confidence: 99%

CO and Dust Properties in the TW Hya Disk from High-resolution ALMA Observations

Huang

Andrews

Cleeves

et al. 2018

ApJ

183

202

View full text Add to dashboard Cite

We analyze high angular resolution ALMA observations of the TW Hya disk to place constraints on the CO and dust properties. We present new, sensitive observations of the 12 CO J = 3 − 2 line at a spatial resolution of 8 AU (0. 14). The CO emission exhibits a bright inner core, a shoulder at r ≈ 70 AU, and a prominent break in slope at r ≈ 90 AU. Radiative transfer modeling is used to demonstrate that the emission morphology can be reasonably reproduced with a 12 CO column density profile featuring a steep decrease at r ≈ 15 AU and a secondary bump peaking at r ≈ 70 AU. Similar features have been identified in observations of rarer CO isotopologues, which trace heights closer to the midplane. Substructure in the underlying gas distribution or radially varying CO depletion that affects much of the disk's vertical extent may explain the shared emission features of the main CO isotopologues. We also combine archival 1.3 mm and 870 µm continuum observations to produce a spectral index map at a spatial resolution of 2 AU. The spectral index rises sharply at the continuum emission gaps at radii of 25, 41, and 47 AU. This behavior suggests that the grains within the gaps are no larger than a few millimeters. Outside the continuum gaps, the low spectral index values of α ≈ 2 indicate either that grains up to centimeter size are present, or that the bright continuum rings are marginally optically thick at millimeter wavelengths.

show abstract

“…Previous studies of 1-3 Myr old disks have found evidence for a low CO abundance relative to dust throughout the disk (Dutrey et al 2003;Chapillon et al 2008;Williams & Best 2014;Hardy et al 2015;Long et al 2017). Ansdell et al (2016) used observations of optically thin 13 CO and C 18 O emission to measure the gas-to-dust ratios of 62 disks in 1-3 Myr old Lupus complex, finding that the majority of sources had a gas-to-dust ratio below the ISM value of 100 assuming an ISM abundance of CO relative to H 2 (see also Miotello et al 2017).…”

Section: Comparing Dust and Comentioning

confidence: 99%

Measurement of Circumstellar Disk Sizes in the Upper Scorpius OB Association with ALMA

Barenfeld

Carpenter

Sargent

et al. 2017

ApJ

100

144

View full text Add to dashboard Cite

We present detailed modeling of the spatial distributions of gas and dust in 57 circumstellar disks in the Upper Scorpius OB Association observed with ALMA at submillimeter wavelengths. We fit power-law models to the dust surface density and CO J=3-2 surface brightness to measure the radial extent of dust and gas in these disks. We found that these disks are extremely compact: the 25 highest signal-to-noise disks have a median dust outer radius of 21 au, assuming an R 1 -dust surface density profile. Our lack of CO detections in the majority of our sample is consistent with these small disk sizes assuming the dust and CO share the same spatial distribution. Of seven disks in our sample with well-constrained dust and CO radii, four appear to be more extended in CO, although this may simply be due to the higher optical depth of the CO. Comparison of the Upper Sco results with recent analyses of disks in Taurus, Ophiuchus, and Lupus suggests that the dust disks in Upper Sco may be approximately three times smaller in size than their younger counterparts, although we caution that a more uniform analysis of the data across all regions is needed. We discuss the implications of these results for disk evolution.

show abstract

An ALMA Survey of CO Isotopologue Emission from Protoplanetary Disks in Chamaeleon I

Cited by 137 publications

References 116 publications

Hubble Space Telescope Scattered-light Imaging and Modeling of the Edge-on Protoplanetary Disk ESO-Hα 569

Hubble Space Telescope Scattered-light Imaging and Modeling of the Edge-on Protoplanetary Disk ESO-Hα 569

CO and Dust Properties in the TW Hya Disk from High-resolution ALMA Observations

Measurement of Circumstellar Disk Sizes in the Upper Scorpius OB Association with ALMA

Contact Info

Product

Resources

About