Issue |
A&A
Volume 515, June 2010
|
|
---|---|---|
Article Number | A15 | |
Number of page(s) | 9 | |
Section | Astrophysical processes | |
DOI | https://doi.org/10.1051/0004-6361/200913678 | |
Published online | 31 May 2010 |
Kerr geodesics, the Penrose process and jet collimation by a black hole
1
LERMA-UPMC, Université Pierre et Marie Curie, Observatoire de Paris, CNRS, UMR 8112, 3 rue Galilée, 94200 Ivry-sur-Seine, France e-mail: jerome.gariel@upmc.fr; gmarcilhacy@hotmail.com
2
School of Mathematical Sciences,
Queen Mary, University of London,
Mile End Road, London E1 4NS, UK e-mail: m.a.h.maccallum@qmul.ac.uk
3
Laboratório Nacional de Computação Científica,
25651-070 Petrópolis RJ, Brazil e-mail: nilton.santos@upmc.fr
Received:
16
November
2009
Accepted:
10
February
2010
Aims. We re-examine the possibility that astrophysical jet collimation may arise from the geometry of rotating black holes and the presence of high-energy particles resulting from a Penrose process, without the help of magnetic fields.
Methods. Our analysis uses the Weyl coordinates, which are revealed better adapted to the desired shape of the jets. We numerically integrate the 2D-geodesics equations.
Results. We give a detailed study of these geodesics and
give several numerical examples. Among them are a set of perfectly
collimated geodesics with asymptotes ρ = parallel to the z-axis, with
only depending on the ratios
and
, where a and M are
the parameters of the
Kerr black hole, E the particle energy and
the Carter's
constant.
Key words: black hole physics / acceleration of particules / relativistic processes
© ESO, 2010
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.