Relativistic Acceleration of Magnetically Driven Jets

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

23 pages, 7 eps figures, submitted to ApJ

Scientific paper

10.1086/375579

We present an analytical model for describing highly relativistic acceleration of magnetically driven jets, within the framework of ideal MHD for cold, stationary and axisymmetric outflows. Our novel procedure is to treat the wind equation as an algebraic relation between the relativistic Alfv\'{e}n Mach-number and the poloidal electric to toroidal magnetic field amplitudes ratio $\xi$. This allows us to obtain easily the wind solutions for trans-fast-magnetosonic flows, together with the required range of $\xi$. Then, to determine the spatial variation of $\xi$, we solve approximately the Grad-Shafranov equation applied to a jet flow ejected with a very large total specific energy $E$ and confined within a very small opening angle. Our trans-fast-magnetosonic model provides a closed-form expression for the transition from a magnetically dominated flow to a kinetic-energy dominated one, which occurs in the sub-asymptotic region far beyond the light cylinder of the radius $R_{\rm L}$. Importantly, we find that the equipartition between magnetic and kinetic energies is realized at a cylindrical radius of order of $R_{\rm L}E/c^{2}$, and confirm that the further conversion of magnetic to kinetic energy proceeds logarithmically with distance in the asymptotic region. Finally, we discuss briefly the astrophysical implications of our model for jets originating from active galactic nuclei.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Relativistic Acceleration of Magnetically Driven Jets does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Relativistic Acceleration of Magnetically Driven Jets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relativistic Acceleration of Magnetically Driven Jets will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-476284

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.