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EPoS |
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EPoS Contribution
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Resolving the disk-jet accretion connection for forming massive stars
Katharine G. Johnston UoLincoln, Lincoln, UK | |
| Since the discovery of dust-continuum and maser-line outbursts from a handful of massive forming stars, there has been an accompanying burst of scientific interest in variable accretion onto MYSOs. Recent observations of highly structured and unstable disks around MYSOs have provided a possible mechanism to explain their episodic accretion. An additional record of their recent accretion history can be derived from observations of jets. We have observed six MYSOs with ionized jets with both ALMA and e-MERLIN to resolve the accretion and jet structures down to a matched resolution of ~40mas (~100au). We present our first results from these observations, which aim to respectively assess of the stability of the material around these MYSOs using the observed circumstellar density, temperature and kinematic structure, and to resolve the knots and determine the width and collimation regions of their associated jets. Comparing these two sets of observations to look for trends in the jet and circumstellar properties and structure, we aim to observationally confirm whether there is a connection between unstable disks with sub-structure and episodic jets with knots, establishing that unstable disks are a route to the production of accretion bursts. | |
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| Caption: JVLA 6 GHz image of G133.7150+1.215 (W3 IRS 5) taken in 2018 showing multiple knots emanating from the driving source (Obonyo et al. 2021). The e-MERLIN 6.5 GHz observation (blue contours at 65 microJy x 4,5,7) taken in 2021 resolves the central sources and lobes. Arrows show the displacements seen in the fast knots between the e-MERLIN and VLA epochs. A second jet system is seen bottom right. Spectral indices (not shown here) indicate that the driving sources are thermal whilst many of the lobes are non-thermal (Purser et al. 2021). | |
| Collaborators: M. Hoare, Leeds, UK L. Maud, ESO, DE R. Kuiper, UDE, DE S. Purser, SSS, IE W. Obonyo, TUK, KY |
Relevant topic(s): Accretion Disks High-Mass SF |
| Relevant Big Question: Do unstable disks produce accretion bursts? | |