1. Angular momentum transport via gravitational instability in the Elias 2-27 disc
- Author
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Longarini, Cristiano, Lodato, Giuseppe, Clarke, Cathie J., Speedie, Jessica, Paneque-Carreno, Teresa, Arrigoni, Edoardo, Curone, Pietro, Toci, Claudia, and Hall, Cassandra
- Subjects
Astrophysics - Earth and Planetary Astrophysics - Abstract
Gravitational instability is thought to be one of the main drivers of angular momentum transport in young protoplanetary discs. The disc around Elias 2-27 offers a unique example of gravitational instability at work. It is young and massive, displaying two prominent spiral arms in dust continuum emission and global non-axisymmetric kinematic signatures in molecular line data. In this work, we used archival ALMA observations of $^{13}$CO line emission to measure the efficiency of angular momentum transport in the Elias 2-27 system through the kinematic signatures generated by gravitational instability, known as 'GI wiggles'. Assuming the angular momentum is transported by the observed spiral structure and leveraging previously-derived dynamical disc mass measurements, the amount of angular momentum transport we found corresponds to an $\alpha-$viscosity of $\alpha=0.038\pm0.018$. This value implies an accretion rate onto the central star of $\log_{10}\dot{M}_\star=-6.99\pm0.17\text{M}_\odot/\text{yr, which}$ reproduces the one observed value of $\log_{10}\dot{M}_{\star,\text{obs}}=-7.2\pm0.5\text{M}_\odot/\text{yr }$ very well. The excellent agreement we have found serves as further proof that gravitational instability is the main driver of angular momentum transport acting in this system., Comment: Accepted for publication in A&A letters, 6 pages, 3 images
- Published
- 2024
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