期刊
ASTRONOMY & ASTROPHYSICS
卷 649, 期 -, 页码 -出版社
EDP SCIENCES S A
DOI: 10.1051/0004-6361/202039733
关键词
stars: pre-main sequence; protoplanetary disks; planets and satellites: formation; submillimeter: general
资金
- Italian Ministero dell Istruzione, Universita e Ricerca through the grant Progetti Premiali 2012 -iALMA (CUP lll)
- Deutsche Forschungs-gemeinschaft (DFG, German Research Foundation) [FOR 2634/1 TE 1024/1-1]
- DFG cluster of excellence Origins
- European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant [823823]
- European Research Council (ERC) via the ERC Synergy Grant ECOGAL [855130]
- ESO Fellowship
- European Research Council under the Horizon 2020 Framework Program via the ERC Advanced Grant [83 24 28]
- MCIU-AEI (Spain) (FEDER) [AYA2017-84390-C2-R]
- Science and Technology Foundation of Portugal (FCT) [IF/00194/2015, PTDC/FIS-AST/28731/2017, UIDB/00099/2020]
- Fundação para a Ciência e a Tecnologia [PTDC/FIS-AST/28731/2017] Funding Source: FCT
A comprehensive study on the CO extent relative to dust in Lupus clouds revealed that CO emission is more extended than dust continuum, and dust evolution is more prominent in compact dusty disks. The majority of disks have similar size ratios, suggesting that the bulk of the disk population may behave alike and be in a similar evolutionary stage.
We performed a comprehensive demographic study of the CO extent relative to dust of the disk population in the Lupus clouds in order to find indications of dust evolution and possible correlations with other disk properties. We increased the number of disks of the region with measured R-CO and R-dust from observations with the Atacama Large Millimeter/submillimeter Array to 42, based on the gas emission in the (CO)-C-12 J = 2-1 rotational transition and large dust grains emission at similar to 0.89 mm. The CO integrated emission map is modeled with an elliptical Gaussian or Nuker function, depending on the quantified residuals; the continuum is fit to a Nuker profile from interferometric modeling. The CO and dust sizes, namely the radii enclosing a certain fraction of the respective total flux (e.g., R-68%), are inferred from the modeling. The CO emission is more extended than the dust continuum, with a R-68%(CO)/R-68%(dust) median value of 2.5, for the entire population and for a subsample with high completeness. Six disks, around 15% of the Lupus disk population, have a size ratio above 4. Based on thermo-chemical modeling, this value can only be explained if the disk has undergone grain growth and radial drift. These disks do not have unusual properties, and their properties spread across the population's ranges of stellar mass (M-star), disk mass (M-disk), CO and dust sizes (R-CO, R-dust), and mass accretion of the entire population. We searched for correlations between the size ratio and M-star, M-disk, R-CO, and R-dust: only a weak monotonic anticorrelation with the R-dust is found, which would imply that dust evolution is more prominent in more compact dusty disks. The lack of strong correlations is remarkable: the sample covers a wide range of stellar and disk properties, and the majority of the disks have very similar size ratios. This result suggests that the bulk of the disk population may behave alike and be in a similar evolutionary stage, independent of the stellar and disk properties. These results should be further investigated, since the optical depth difference between CO and dust continuum might play a major role in the observed size ratios of the population. Lastly, we find a monotonic correlation between the CO flux and the CO size. The results for the majority of the disks are consistent with optically thick emission and an average CO temperature of around 30 K; however, the exact value of the temperature is difficult to constrain.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据