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We have identified spectral features in the late-time X-ray afterglow of the unusually long, slow-decaying GRB 130925A using NuSTAR, Swift-XRT, and Chandra. A spectral component in addition to an absorbed power-law is required at $>4sigma$ significan ce, and its spectral shape varies between two observation epochs at $2times10^5$ and $10^6$ seconds after the burst. Several models can fit this additional component, each with very different physical implications. A broad, resolved Gaussian absorption feature of several keV width improves the fit, but it is poorly constrained in the second epoch. An additive black body or second power-law component provide better fits. Both are challenging to interpret: the blackbody radius is near the scale of a compact remnant ($10^8$ cm), while the second powerlaw component requires an unobserved high-energy cutoff in order to be consistent with the non-detection by Fermi-LAT.
The long, bright gamma-ray burst GRB 070125 was localized by the Interplanetary Network. We present light curves of the prompt gamma-ray emission as observed by Konus-WIND, RHESSI, Suzaku-WAM, and textit{Swift}-BAT. We detail the results of joint spe ctral fits with Konus and RHESSI data. The burst shows moderate hard-to-soft evolution in its multi-peaked emission over a period of about one minute. The total burst fluence as observed by Konus is $1.79 times 10^{-4}$ erg/cm$^2$ (20 keV--10 MeV). Using the spectroscopic redshift $z=1.548$, we find that the burst is consistent with the ``Amati $E_{peak,i}-E_{iso}$ correlation. Assuming a jet opening angle derived from broadband modeling of the burst afterglow, GRB 070125 is a significant outlier to the ``Ghirlanda $E_{peak,i}-E_gamma$ correlation. Its collimation-corrected energy release $E_gamma = 2.5 times 10^{52}$ ergs is the largest yet observed.
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