Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-03-06
Mon.Not.Roy.Astron.Soc.351:292-296,2004
Astronomy and Astrophysics
Astrophysics
5 pages, no figures. MNRAS in press
Scientific paper
10.1111/j.1365-2966.2004.07781.x
We discuss the possible simultaneously UV/optical emission accompanying Gamma-ray bursts (GRBs). We show that as long as the intrinsic spectrum of GRB can extend to $\sim$10 GeV or higher, there is a large amount of relativistic $e^\pm$ pairs generated due to the annihilation of the soft $\gamma-$rays with the very energetic photons, which dominates over the electrons/positrons associated with the fireball, no matter the fireball is highly magnetized or not (For the highly magnetized fireball, the magnetic field is ordered, the high linear polarization of the multi-wavelength emission is expected). We find that these $e^\pm$ pairs can power an UV flash with $m\simeq 12-13{\rm th}$ magnitude, and the corresponding optical emission can be up to $m_{\rm R}\simeq15-16{\rm th}$ magnitude. Such bright UV emission can be detected by the upcoming satellite Swift, planned for launch in early 2004. The behavior of the optical-UV spectrum ($F_{\nu}\propto \nu^{5/2}$) differs significantly from that of the reverse shock emission ($F_{\nu}\propto \nu^{-\beta/2}$, $\beta \simeq 2.2$), which is a signature of the emission accompanying with GRB. The mild optical emission can be detected with the ROTSE-IIIa telescope system, if the response to the GRB alert is fast enough.
Y. Z. Fan.
Wei Da-Ming
No associations
LandOfFree
UV/Optical Emission Accompanying Gamma-ray Burst 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 UV/Optical Emission Accompanying Gamma-ray Burst, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and UV/Optical Emission Accompanying Gamma-ray Burst will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-653658