Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-03-02
Astronomy and Astrophysics
Astrophysics
3 pages, 2 figures, oral presentation on 2nd Rome Workshop on Gamma-Ray Bursts in the Afterglow Era
Scientific paper
10.1007/10853853_82
We perform fully relativistic hydrodynamic simulations of the deceleration and lateral expansion of a relativistic jet as it expands into an ambient medium. The hydrodynamic calculations use a 2D adaptive mesh refinement (AMR) code, which provides adequate resolution of the thin shell of matter behind the shock. We find that the sideways propagation is different than predicted by simple analytic models. The physical conditions at the sides of the jet are found to be significantly different than at the front of the jet, and most of the emission occurs within the initial opening angle of the jet. The light curves, as seen by observers at different viewing angles with respect to the jet axis, are then calculated assuming synchrotron emission. For an observer along the jet axis, we find a sharp achromatic `jet break' in the light curve at frequencies above the typical synchrotron frequency, at $t_{jet}\approx 5.8(E_{52}/n_1)^{1/3}(\theta_0/0.2)^{8/3}$ days, while the temporal decay index $\alpha$ ($F_{\nu}\propto t^{\alpha}$) after the break is steeper than $-p$ ($\alpha=-2.85$ for $p=2.5$). At larger viewing angles $t_{jet}$ increases and the jet break becomes smoother.
Granot Jonathan
Hughes Philip A.
Miller Mark
Piran Tsvi
Suen W.-M.
No associations
LandOfFree
Light Curves from an Expanding Relativistic Jet 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 Light Curves from an Expanding Relativistic Jet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Light Curves from an Expanding Relativistic Jet will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-301595