EPJ Web of Conferences
Volume 61, 2013The Innermost Regions of Relativistic Jets and Their Magnetic Fields
|Number of page(s)||6|
|Published online||09 December 2013|
Is the disc thermal state controlling the Blandford & Znajek/Blandford & Payne jet dichotomy?
UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041, France
a e-mail: Jonathan.Ferreira@obs.ujf-grenoble.fr
Published online: 9 December 2013
It is generally assumed that Blandford & Payne jets can carry a significant fraction of the accretion power released in the underlying disc. But this fraction actually strongly depends on the disc aspect ratio h/r, hence on the disc thermal properties. In fact, Jet Emitting discs (JEDs) cannot power BP-like jets if they are thicker than h/r ≃ 0.2. On the other hand, the power of Blandford & Znajek jets depends mostly on the magnitude of the vertical magnetic field Bz. If this magnetic field is dragged in by the accretion flow, then its magnitude depends also on the disc aspect ratio and the BZ jet maximum power is achieved with Magnetically Arrested Discs (MADs).
If the innermost disc regions are geometrically thin or slim, they are in a JED state with both BP and BZ jets launched. It is shown that the BZ jet acts only as a highly relativistic and shinning spine, carrying a tiny fraction of the overall jet power. If the innermost disc regions are geometrically thick, they are in a MAD state where only BZ jets are allowed. We expect quite di↵erent jet morphologies in the two cases.
© Owned by the authors, published by EDP Sciences, 2013
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.