2021/04/30 by Benedetta Veronesi, Teresa Paneque-Carreno, Teresa Paneque-Carreño +5 · 1 citation
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Debris disk #Galaxy rotation curve #Gravitation #Planet #Planetesimal #Rotation (mathematics) #Spiral galaxy #Star (game theory) #Stellar, planetary, and galactic studies #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.3847/2041-8213/abfe6a
14 pages, 9 figures, 2 tables, accepted for publication on ApJL
openalex created_date 2021/04/26 · arxiv created 2021/05/07 · openalex publication_date 2021/06/01 · arxiv updated 2021/06/30 · openalex updated_date 2026/08/06
Abstract Recent multi-wavelength Atacama Large Millimeter/submillimeter Array (ALMA) observations of the protoplanetary disk orbiting around Elias 2–27 revealed a two-armed spiral structure. The observed morphology, together with the young age of the star and the disk-to-star mass ratio estimated from dust-continuum emission, make this system a perfect laboratory to investigate the role of self-gravity in the early phases of star formation. This is particularly interesting if we consider that gravitational instabilities could be a fundamental first step for the formation of planetesimals and planets. In this Letter, we model the rotation curve obtained by CO data of Elias 2–27 with a theoretical rotation curve, including both the disk self-gravity and the star contribution to the gravitational potential. We compare this model with a purely Keplerian one and with a simple power-law function. We find that (especially for the 13 CO isotopologue) the rotation curve is better described by considering not only the star, but also the disk self-gravity. We are thus able to obtain for the first time a dynamical estimate of the disk mass of 0.08 ± 0.04 M ⊙ and the star mass of 0.46 ± 0.03 M ⊙ (in the more general case), the latter being comparable with previous estimates. From these values, we derive that the disk is 17% of the star mass, meaning that it could be prone to gravitational instabilities. This result would strongly support the hypothesis that the two spiral arms are generated by gravitational instabilities.