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Unveiling a magnetized jet from a low-mass protostar.

ABSTRACT: Protostellar jets are one of the most intriguing signposts in star formation. Recent detection of a jet rotation indicates that they can carry away angular momenta from the innermost edges of the disks, allowing the disks to feed the central protostars. In current jet-launching models, magnetic fields are required to launch and collimate the jets, however, observationally, it is still uncertain if magnetic fields are really present in the jets. Here we report a clear detection of SiO line polarization in the HH 211 protostellar jet. Since this line polarization has been attributed to the Goldreich-Kylafis effect in the presence of magnetic field, our observations show convincingly the presence of magnetic field in a jet from a low-mass protostar. The implied magnetic field could be mainly toroidal, as suggested in current jet-launching models, in order to collimate the jet at large distances.

SUBMITTER: Lee CF

PROVIDER: S-EPMC6219518 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Unveiling a magnetized jet from a low-mass protostar.

Lee Chin-Fei CF Hwang Hsiang-Chih HC Ching Tao-Chung TC Hirano Naomi N Lai Shih-Ping SP Rao Ramprasad R Ho Paul T P PTP

Nature communications 20181106 1

Protostellar jets are one of the most intriguing signposts in star formation. Recent detection of a jet rotation indicates that they can carry away angular momenta from the innermost edges of the disks, allowing the disks to feed the central protostars. In current jet-launching models, magnetic fields are required to launch and collimate the jets, however, observationally, it is still uncertain if magnetic fields are really present in the jets. Here we report a clear detection of SiO line polari ...[more]

PMID: 30401928

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