Gamma-ray bursts (GRBs) are by far the most powerful explosions in the universe. Over the past two decades, several GRB energy and luminosity correlations were discovered for long gamma-ray bursts, which are bursts wh...Gamma-ray bursts (GRBs) are by far the most powerful explosions in the universe. Over the past two decades, several GRB energy and luminosity correlations were discovered for long gamma-ray bursts, which are bursts whose observed duration exceeds 2 seconds. One important correlation, the Amati relation, involves the observed peak energy, <em>E</em><sub><em>p,obs</em></sub>, in the <em>v</em>F<em><sub>v</sub></em> spectrum and the equivalent isotropic energy, <em>E</em><sub><em>iso</em></sub>. For many years, it was believed that the Amati correlation applied only to long GRBs. In this paper, we use a recent data sample that includes both long and short GRBs to re-examine the issue of whether the Amati correlation applies to long GRBs only. Our results indicate that although short bursts do not follow the Amati relation in the strict sense, they do exhibit a correlation between the intrinsic peak energy, <em>E</em><em><sub>p,i</sub></em>, and <em>E<sub>iso</sub></em> that is very similar to the Amati relation but with a different normalization and slope. The paper also discusses the physical interpretation of this correlation in the context of the internal shock model.展开更多
Gamma-ray bursts (GRBs) are the most intense and powerful explosions in the universe. Based on their observed duration, they are traditionally divided into long bursts whose observed duration equals or exceeds 2 s, an...Gamma-ray bursts (GRBs) are the most intense and powerful explosions in the universe. Based on their observed duration, they are traditionally divided into long bursts whose observed duration equals or exceeds 2 s, and short bursts whose observed duration is less than 2 s. Several GRB energy and luminosity correlations have been discovered for long gamma-ray bursts. Two important correlations are the Amati relation and the Yonetoku relation. The Amati relation is a correlation between the intrinsic peak energy, E<sub>p</sub><sub>,i</sub>, obtained from the νF<sub>ν</sub> spectrum and the equivalent isotropic energy, E<sub>iso</sub>, while the Yonetoku relation is a correlation between E<sub>p,i</sub> and the peak isotropic luminosity, L<sub>iso</sub>. In this paper, we use a recent data sample that includes both long and short GRBs to compare these two correlations for the two groups of bursts. We also compare the E<sub>iso</sub>-L<sub>iso</sub> plane for these two types of bursts. Our results indicate that both long and short bursts adhere to these two correlations but with different normalizations. We also find that the E<sub>iso</sub>-L<sub>iso</sub> plane is similar for both types of GRBs but is shifted to lower values of E<sub>iso</sub> for short GRBs.展开更多
文摘Gamma-ray bursts (GRBs) are by far the most powerful explosions in the universe. Over the past two decades, several GRB energy and luminosity correlations were discovered for long gamma-ray bursts, which are bursts whose observed duration exceeds 2 seconds. One important correlation, the Amati relation, involves the observed peak energy, <em>E</em><sub><em>p,obs</em></sub>, in the <em>v</em>F<em><sub>v</sub></em> spectrum and the equivalent isotropic energy, <em>E</em><sub><em>iso</em></sub>. For many years, it was believed that the Amati correlation applied only to long GRBs. In this paper, we use a recent data sample that includes both long and short GRBs to re-examine the issue of whether the Amati correlation applies to long GRBs only. Our results indicate that although short bursts do not follow the Amati relation in the strict sense, they do exhibit a correlation between the intrinsic peak energy, <em>E</em><em><sub>p,i</sub></em>, and <em>E<sub>iso</sub></em> that is very similar to the Amati relation but with a different normalization and slope. The paper also discusses the physical interpretation of this correlation in the context of the internal shock model.
文摘Gamma-ray bursts (GRBs) are the most intense and powerful explosions in the universe. Based on their observed duration, they are traditionally divided into long bursts whose observed duration equals or exceeds 2 s, and short bursts whose observed duration is less than 2 s. Several GRB energy and luminosity correlations have been discovered for long gamma-ray bursts. Two important correlations are the Amati relation and the Yonetoku relation. The Amati relation is a correlation between the intrinsic peak energy, E<sub>p</sub><sub>,i</sub>, obtained from the νF<sub>ν</sub> spectrum and the equivalent isotropic energy, E<sub>iso</sub>, while the Yonetoku relation is a correlation between E<sub>p,i</sub> and the peak isotropic luminosity, L<sub>iso</sub>. In this paper, we use a recent data sample that includes both long and short GRBs to compare these two correlations for the two groups of bursts. We also compare the E<sub>iso</sub>-L<sub>iso</sub> plane for these two types of bursts. Our results indicate that both long and short bursts adhere to these two correlations but with different normalizations. We also find that the E<sub>iso</sub>-L<sub>iso</sub> plane is similar for both types of GRBs but is shifted to lower values of E<sub>iso</sub> for short GRBs.
