Astronomy and Astrophysics – Astrophysics
Scientific paper
1998-02-02
Astrophys.J. 498 (1998) L31
Astronomy and Astrophysics
Astrophysics
9 pages LaTeX, submitted to ApJL
Scientific paper
10.1086/311311
Cosmological gamma-ray bursts (GRBs) and their afterglows seem to result from dissipation of bulk energy in relativistic outflows, but their engine has not been unambiguously identified. The engine could be a young pulsar formed from accretion induced collapse with a dynamo amplified field. Elsewhere, we suggest that such a ``Usov type'' strong field pulsar may help explain the bimodal distribution in GRB durations. Here we discuss possible roles of a pulsar for the afterglow. We derive the expected bolometric luminosity decay. The extracted rotational energy could dissipate by shocks or by large amplitude electromagnetic waves (LAEMW). The simplest LAEMW approach predicts a slower decay in observed afterglow peak frequency and faster decay in flux than the simplest blast-wave model, though more complicated models of both can provide different dependences. LAEMW do not require the rapid magnetic field amplification demanded of the blast-wave approach because the emission originates from a nearly fixed radius. Different time dependent behavior of GRB and post-GRB emission is also predicted. Observational evidence for a pulsar in a GRB would make some GRB engine models, such as neutron star mergers and black holes unlikely. Therefore, the question of whether a pulsar is present is an important one even if it could drive a canonical fireball.
Blackman Eric G.
Yi Insu
No associations
LandOfFree
On Fueling Gamma-Ray Bursts and Their Afterglows with Pulsars 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 On Fueling Gamma-Ray Bursts and Their Afterglows with Pulsars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On Fueling Gamma-Ray Bursts and Their Afterglows with Pulsars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-474619