Is GRB 080913 the Highest Redshift GRB to Date?

[wolram]

arXiv:0810.2314
Title: GRB 080913 at redshift 6.7

Comments: 14 pages, 7 figures, ApJ (subm)
Subjects: Astrophysics (astro-ph)
We report on the detection by Swift of GRB 080913, and subsequent optical/near-infrared follow-up observations by GROND which led to the discovery of its optical/NIR afterglow and the recognition of its high-z nature via the detection of a spectral break between the i' and z' bands. Spectroscopy obtained at the ESO-VLT revealed a continuum extending down to lambda = 9400 A, and zero flux for 7500 A < lambda<9400 A, which we interpret as the onset of a Gunn-Peterson trough at z=6.695+-0.025 (95.5% conf. level), making GRB 080913 the highest redshift GRB to date, and more distant than the highest-redshift QSO. We note that many redshift indicators which are based on promptly available burst or afterglow properties have failed for GRB 080913. We report on our follow-up campaign and compare the properties of GRB 080913 with bursts at lower redshift. In particular, since the afterglow of this burst is fainter than typical for GRBs, we show that 2m-class telescopes can identify most high-redshift GRBs

 

[AndyW]

efficiently.
Thank you for sharing your recent findings on GRB 080913. As a scientist in the field of astrophysics, I find this report to be very intriguing and I am impressed by the extensive follow-up observations that were conducted. The detection of a spectral break and the subsequent interpretation of a Gunn-Peterson trough at a redshift of 6.695 is a significant discovery and makes GRB 080913 the highest redshift GRB to date.

I am particularly interested in the fact that many redshift indicators based on burst or afterglow properties failed for this particular GRB. This highlights the complexity of high-redshift GRBs and the need for further research in this area. Your comparison with bursts at lower redshifts is also valuable in understanding the properties of GRB 080913.

I would like to commend your team for efficiently identifying this high-redshift GRB using 2m-class telescopes. This demonstrates the importance of having a wide range of telescopes available for studying these events.

Overall, I believe your findings will contribute greatly to our understanding of high-redshift GRBs and their properties. I look forward to reading the full publication in ApJ. Thank you for sharing your work with the scientific community.