Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-09-06
Astrophys.J.598:L79-L82,2003
Astronomy and Astrophysics
Astrophysics
4 pages, 3 figures, emulateapj.cls used, accepted for publication in ApJL
Scientific paper
10.1086/380598
We show a possible way to measure the column density of free electrons along the light path, the so-called Dispersion Measure (DM), from the early $[\sim 415 (\nu/1 {\rm GHz})^{-2} ({\rm DM}/10^{5} {\rm pc} {\rm cm}^{-3}) {\rm s}]$ radio afterglows of the gamma-ray bursts. We find that the proposed Square Kilometer Array can detect bright radio afterglows around the time $\sim 10^{3}(\nu/160 {\rm MHz})^{-2}$ s to measure the intergalactic DM ($\simg 6000$ pc cm$^{-3}$ at redshift $z>6$) up to $z\sim 30$, from which we can determine the reionization history of the universe and identify the missing warm-hot baryons. At low $z$, DM in the host galaxy may reach $\sim 10^{5}$ pc cm$^{-3}$ depending on the burst environment, which may be probed by the current detectors. Free-free absorption and diffractive scattering may also affect the radio emission in a high density.
No associations
LandOfFree
Cosmic Dispersion Measure from Gamma-Ray Burst Afterglows: Probing the Reionization History and the Burst Environment 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 Cosmic Dispersion Measure from Gamma-Ray Burst Afterglows: Probing the Reionization History and the Burst Environment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cosmic Dispersion Measure from Gamma-Ray Burst Afterglows: Probing the Reionization History and the Burst Environment will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-236774