期刊
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
卷 512, 期 3, 页码 3538-3550出版社
OXFORD UNIV PRESS
DOI: 10.1093/mnras/stac621
关键词
accretion, accretion discs; methods: miscellaneous; planets and satellites: formation; protoplanetary discs; binaries: close; submillimetre: planetary systems
资金
- STFC
- Cambridge Trust
- Netherlands Organisation for Scientific Research (NWO) [016.Veni.192.233]
- STFC Ernest Rutherford Fellowship [ST/T003855/1]
- Deutsche Forschungs-Gemeinschaft (DFG, German Research Foundation) [FOR 2634/1 TE 1024/1-1]
- European Union [823823]
In recent years, a correlation between mass accretion rates onto new-born stars and their protoplanetary disc masses has been observed. However, highly accreting sources with low disc masses in more evolved regions remain puzzling. This paper hypothesizes that the presence of a stellar companion truncating the disc can explain these outliers. The hypothesis is supported by statistical analysis, which shows that binary systems have higher accretion rates compared to single-star systems.
In recent years, a correlation between mass accretion rates onto new-born stars and their protoplanetary disc masses was detected in nearby young star-forming regions. Although such a correlation can be interpreted as due to viscous-diffusion processes in the disc, highly accreting sources with low disc masses in more evolved regions remain puzzling. In this paper, we hypothesize that the presence of a stellar companion truncating the disc can explain these outliers. First, we searched the literature for information on stellar multiplicity in Lupus, Chamaeleon I, and Upper Sco, finding that roughly 20 per cent of the discs involved in the correlation are in binaries or higher order multiple stellar systems. We prove with high statistical significance that at any disc mass these sources have systematically higher accretion rates than those in single-stars, with the bulk of the binary population being clustered around M-disc/ M-acc approximate to 0.1 Myr. We then run coupled gas and dust one-dimensional evolutionary models of tidally truncated discs to be compared with the data. We find that these models are able to reproduce well most of the population of observed discs in Lupus and Upper Sco, even though the unknown eccentricity of each binary prevents an object by object comparison. In the latter region, the agreement improves if the grain coagulation efficiency is reduced, as may be expected in discs around close binaries. Finally, we mention that thermal winds and sub-structures can be important in explaining few outlying sources.
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