On the Kinematic Origin of the Luminosity-Pulse Lag Relationship in Gamma-ray Bursts
نویسنده
چکیده
This paper presents an interpretation based on gamma-ray burst source kinematics for the relationship found by Norris et al. between peak luminosity and energy-dependent pulse lag. I argue that the correlation should instead be between number luminosity and pulse lag. This interpretation improves the least-squares fit of this correlation for the known bursts by 25 percent or more. It also suggests a distance estimation scheme. I propose that this relationship is due to the variation in line-of-sight velocity among bursts. This interpretation allows one to speculate on the range of gamma-ray burst expansion velocities or the size of their jet opening angles. Subject headings: gamma rays: bursts — gamma rays: theory
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