Publication Date:
2020-01-24
Description:
We present the first detection of the $^{13}ext{C}^{17}ext{O}$ J = 3–2 transition toward the HL? Tau protoplanetary disc. We find significantly more gas mass (at least a factor of 10 higher) than has been previously reported using $ext{C}^{18}ext{O}$ emission. This brings the observed total disc mass to 0.2? M⊙, which we consider to be a conservative lower limit. Our analysis of the Toomre Q profile suggests that this brings the disc into the regime of gravitational instability. The radial region of instability (50–110? au) coincides with the location of a proposed planet-carved gap in the dust disc, and a spiral in the gas. We therefore propose that if the origin of the gap is confirmed to be due to a forming giant planet, then it is likely to have formed via the gravitational fragmentation of the protoplanetary disc.
Print ISSN:
1745-3925
Electronic ISSN:
1745-3933
Topics:
Physics