论文标题
中间分离二进制系统中的行星形成
Planet formation in intermediate-separation binary systems
论文作者
论文摘要
我们报告了中间分离二进制系统KK OPH和HD 144668在毫米波长中的第一个表征。在这两个系统中,在毫米连续排放中都检测到了训练和训练圆盘,但在$^{13} $ co non C $^{18} $ o线中均未检测到。即使仅对圆盘结构进行了少量解析,我们也会发现主要盘外区域的大尺度不对称的迹象,这很可能是由于同伴的扰动所致。对于所有恒星来说,派生的灰尘块牢固地超过了碎屑盘水平。初选的圆盘上的灰尘是次要的三倍。在HD 144668的情况下,主要和次级的不透明度指数的差距为0.69,这可能是次级盘更紧凑的结果。气体块上的上限意味着在这些光盘中的任何一个小于0.1 m $ _ {\ textrm {jup}} $中,这意味着巨型行星在其中不再形成。考虑到迄今为止在中间分离二进制中尚无大规模气盘(即,在几百个AU分离处的二进制文件),这为推测其二进制性是否会导致气体的去除,这为潮汐截断并因此缩短了积聚的时间尺度。迫切需要在这方面进行更多的系统研究。
We report the first characterisation of the individual discs in the intermediate separation binary systems KK Oph and HD 144668 at millimetre wavelengths. In both systems the circum-primary and the circum-secondary discs are detected in the millimetre continuum emission, but not in $^{13}$CO nor C$^{18}$O lines. Even though the disc structure is only marginally resolved, we find indications of large-scale asymmetries in the outer regions of the primary discs, most likely due to perturbation by the companion. The derived dust masses are firmly above debris disc level for all stars. The primaries have about three times more dust in their discs than the secondaries. In the case of HD 144668 the opacity spectral index of the primary and secondary differ by the large margin of 0.69 which may be a consequence of the secondary disc being more compact. Upper limits on the gas masses imply less than 0.1 M$_{\textrm{jup}}$ in any of these discs, meaning that giant planets can no longer form in them. Considering that there have been no massive gas discs identified to date in intermediate separation binaries (i.e., binaries at a few hundred au separation), this opens space for speculation whether their binarity causes the removal of gas, with tidal interaction truncating the discs and hence shortening the accretion timescale. More systematic studies in this respect are sorely needed.