English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present multi-epoch VLBA imaging of the 28SiO v=1 & v=2, J=1-0 maseremission toward the massive YSO Orion Source I. Both SiO transitions wereobserved simultaneously with an angular resolution of ~0.5 mas (~0.2 AU ford=414 pc). Here we explore the global properties and kinematics of the emissionthrough two 19-epoch animated movies spanning 21 months (2001 March 19 to 2002December 10). These movies provide the most detailed view to date of thedynamics and temporal evolution of molecular material within ~20-100 AU of amassive (~>8M_sun) YSO. The bulk of the SiO masers surrounding Source I lie inan X-shaped locus; emission in the South/East arms is predominantly blueshiftedand in the North and West is predominantly redshifted. In addition, bridges ofintermediate-velocity emission connect the red and blue sides of the emissiondistribution. We have measured proper motions of >1000 maser features and finda combination of radially outward migrations along the four arms and motionstangent to the bridges. We interpret the SiO masers as arising from awide-angle bipolar wind emanating from a rotating, edge-on disk. The detectionof maser features along extended, curved filaments suggests that magneticfields may play a role in launching and/or shaping the wind. Our observationsappear to support a picture in which stars with M ~>8 M_sun form viadisk-mediated accretion. However, we cannot rule out that the Source I disk mayhave been formed or altered following a close encounter. (Abridged).

A Feature Movie of SiO Emission 20-100 AU from the Massive Young Stellar Object Orion Source I