Probing the existence of the Epeak-Eiso correlation in long Gamma Ray Bursts
نویسندگان
چکیده
We probe the existence of the Epeak–Eiso correlation in long GRBs using a sample of 442 BATSE bursts with known Epeak and with redshift estimated through the lag–luminosity correlation. This sample confirms that the rest frame peak energy is correlated with the isotropic equivalent energy. The distribution of the scatter of the points around the best fitting line is similar to that obtained with the 27 bursts with spectroscopic redshifts. We interpret the scatter in the Epeak − Eiso plane as due to the opening angle distribution of GRB jets. By assuming that the collimation corrected energy correlates with Epeak we can derive the observed distribution of the jet opening angles, which turns out to be log–normal with a peak value of ∼ 6.5.
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