2018/03/31 by Bin Ren, Bin 彬 Ren 任, Ruobing Dong +12 · 2 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.3847/2041-8213/aab7f5
published as The Astrophysical Journal Letters, 857 (2018) L9 · 9 pages, 4 figures, Published by ApJ Letters. Updated citations, and fixed equation typos in the Appendix
openalex created_date 2018/03/29 · openalex publication_date 2018/04/10 · arxiv created 2018/06/19 · arxiv updated 2018/06/20 · openalex updated_date 2026/08/05
Large-scale spiral arms have been revealed in scattered light images of a few protoplanetary disks. Theoretical models suggest that such arms may be driven by and co-rotate with giant planets, which has called for remarkable observational efforts to look for them. By examining the rotation of the spiral arms for the MWC 758 system over a 10-yr timescale, we are able to provide dynamical constraints on the locations of their perturbers. We present reprocessed Hubble Space Telescope (HST)/NICMOS F110W observations of the target in 2005, and the new Keck/NIRC2 L'-band observations in 2017. MWC~758's two well-known spiral arms are revealed in the NICMOS archive at the earliest observational epoch. With additional Very Large Telescope (VLT)/SPHERE data, our joint analysis leads to a pattern speed of 0.6^∘+3.3^∘-0.6^∘ yr-1 at 3σ for the two major spiral arms. If the two arms are induced by a perturber on a near-circular orbit, its best fit orbit is at 89 au (0.59"), with a 3σ lower limit of 30 au (0.20"). This finding is consistent with the simulation prediction of the location of an arm-driving planet for the two major arms in the system.