Observing the onset of outflow collimation in a massive protostar
Journal article, 2015
The current paradigm of star formation through accretion disks, and magnetohydrodynamically driven gas ejections, predicts the development of collimated outflows, rather than expansion without any preferential direction. We present radio continuum observations of the massive protostar W75N(B)-VLA 2, showing that it is a thermal, collimated ionized wind and that it has evolved in 18 years from a compact source into an elongated one. This is consistent with the evolution of the associated expanding water-vapor maser shell, which changed from a nearly circular morphology, tracing an almost isotropic outflow, to an elliptical one outlining collimated motions. We model this behavior in terms of an episodic, short-lived, originally isotropic ionized wind whose morphology evolves as it moves within a toroidal density stratification.
Author
C. Carrasco-Gonzalez
Universidad Nacional Autónoma de México
J. M. Torrelles
Spanish National Research Council (CSIC)
J. Canto
Universidad Nacional Autónoma de México
S. Curiel
Universidad Nacional Autónoma de México
G. Surcis
Joint Institute for VLBI in Europe (JIVE)
Wouter Vlemmings
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
H. J. van Langevelde
Leiden University
Joint Institute for VLBI in Europe (JIVE)
C. Goddi
Radboud University
Joint Institute for VLBI in Europe (JIVE)
G. Anglada
Spanish National Research Council (CSIC)
S. W. Kim
Korea Astronomy and Space Science Institute
University of Science and Technology (UST)
J. S. Kim
National Astronomical Observatory of Japan
J. F. Gomez
Spanish National Research Council (CSIC)
Science
00368075 (ISSN) 10959203 (eISSN)
Vol. 348 6230 114-117Magnetic fields and the outflows during the formation and evolution of stars (OUTFLOWMAGN)
European Commission (EC) (EC/FP7/614264), 2014-05-01 -- 2019-04-30.
Subject Categories (SSIF 2011)
Astronomy, Astrophysics and Cosmology
Roots
Basic sciences
DOI
10.1126/science.aaa7216