当前位置：
X-MOL 学术
›
Astron. Astrophys.
›
论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
The dispersion of the Ep, i–Liso correlation of long gamma-ray bursts is partially due to assembling different sources
Astronomy & Astrophysics ( IF 6.5 ) Pub Date : 2024-04-10 , DOI: 10.1051/0004-6361/202449165 M. Maistrello , R. Maccary , C. Guidorzi , L. Amati
Astronomy & Astrophysics ( IF 6.5 ) Pub Date : 2024-04-10 , DOI: 10.1051/0004-6361/202449165 M. Maistrello , R. Maccary , C. Guidorzi , L. Amati
Context. Long gamma-ray burst (GRB) prompt emission shows a correlation between the intrinsic peak energy, Ep, i, of the time-average νFν spectrum and the isotropic-equivalent peak gamma-ray luminosity, Lp, iso, as well as the total released energy, Eiso. The same correlation is found within individual bursts, when time-resolved Ep, i and Liso are considered. These correlations are characterised by an intrinsic dispersion, whose origin is still unknown. Discovering the origin of the correlation and of its dispersion would shed light on the still poorly understood prompt emission and would propel GRBs to powerful standard candles.Aims. We studied the dispersion of both isotropic-equivalent and collimation-corrected time-resolved correlations. We also investigated whether the intrinsic dispersion computed within individual GRBs is different from that obtained including different bursts into a unique sample. We then searched for correlations between key features, such as the Lorentz factor and jet opening angle, and intrinsic dispersion, when the latter is treated as one of the characterising properties.Methods. We performed a time-resolved spectral analysis of 20 long type-II or collapsar-candidate GRBs detected by the Fermi Gamma-ray Burst Monitor with a known redshift and estimates of the jet opening angle and/or the Lorentz factor. Time intervals were determined using Bayesian blocks. Then we carried out a statistical analysis starting from distributions of simulated values of the intrinsic dispersion of each burst in the sample.Results. The collimation-corrected correlation appears to be no less dispersed than the isotropic-equivalent one. Also, individual GRBs are significantly less dispersed than the whole sample. We excluded (at a 4.2σ confidence level) the difference in samples’ sizes as the possible reason, thus confirming that individual GRBs are intrinsically less dispersed than the whole sample. No correlation was found between intrinsic dispersion and other key properties for the few GRBs with available information.Conclusions. The contribution to the dispersion by the jet opening angle is not relevant. Moreover, our results prove that the intrinsic dispersion that affects the Ep, i − Liso correlation is partially, though not entirely, due to assembling different GRBs. We therefore conclude that the presence of different GRBs significantly contributes to the observed dispersion of both time-average Ep, i − Lp, iso and Ep, i − Eiso correlations.
中文翻译：
长伽马射线暴的 Ep、i-Liso 相关性的离散部分是由于不同源的组合造成的
语境。长伽马射线暴 (GRB) 瞬发发射显示了时间平均νF ν谱的固有峰值能量E p, i与各向同性等效峰值伽马射线光度L p, iso之间的相关性作为总释放能量E iso 。当考虑时间分辨的E p、i和L iso时，在各个突发中发现了相同的相关性。这些相关性的特点是存在内在的离散性，其起源仍然未知。发现相关性及其色散的起源将有助于我们了解仍然知之甚少的瞬发辐射，并将推动伽马射线暴发展成为强大的标准烛光。目标。我们研究了各向同性等效和准直校正时间分辨相关性的色散。我们还研究了单个伽玛暴内计算出的固有色散是否与包含不同突发到独特样本中所获得的色散不同。然后，当后者被视为特征属性之一时，我们搜索了洛伦兹因子和射流张角等关键特征与固有色散之间的相关性。方法。我们对费米伽马射线爆发监视器检测到的 20 个长 II 型或塌缩星候选伽玛暴进行了时间分辨光谱分析，具有已知的红移以及喷流张角和/或洛伦兹因子的估计。使用贝叶斯块确定时间间隔。然后，我们从样本中每个突发的固有色散的模拟值分布开始进行统计分析。结果。准直校正相关性似乎并不比各向同性等效相关性更分散。此外，单个伽马射线暴的分散程度明显低于整个样本。我们排除了（在 4.2 σ置信水平下）样本大小的差异作为可能的原因，从而证实了单个伽玛暴本质上比整个样本更不分散。对于具有可用信息的少数伽玛暴，没有发现固有色散与其他关键特性之间的相关性。结论。射流张角对分散的贡献是不相关的。此外，我们的结果证明，影响E p, i − L iso相关性的内在色散部分但不完全是由于不同伽玛暴的组装造成的。因此，我们得出结论，不同伽玛暴的存在显着影响了观察到的时间平均E p, i − L p, iso和E p, i − E iso相关性。
更新日期：2024-04-10
中文翻译：
长伽马射线暴的 Ep、i-Liso 相关性的离散部分是由于不同源的组合造成的
语境。长伽马射线暴 (GRB) 瞬发发射显示了时间平均νF ν谱的固有峰值能量E p, i与各向同性等效峰值伽马射线光度L p, iso之间的相关性作为总释放能量E iso 。当考虑时间分辨的E p、i和L iso时，在各个突发中发现了相同的相关性。这些相关性的特点是存在内在的离散性，其起源仍然未知。发现相关性及其色散的起源将有助于我们了解仍然知之甚少的瞬发辐射，并将推动伽马射线暴发展成为强大的标准烛光。目标。我们研究了各向同性等效和准直校正时间分辨相关性的色散。我们还研究了单个伽玛暴内计算出的固有色散是否与包含不同突发到独特样本中所获得的色散不同。然后，当后者被视为特征属性之一时，我们搜索了洛伦兹因子和射流张角等关键特征与固有色散之间的相关性。方法。我们对费米伽马射线爆发监视器检测到的 20 个长 II 型或塌缩星候选伽玛暴进行了时间分辨光谱分析，具有已知的红移以及喷流张角和/或洛伦兹因子的估计。使用贝叶斯块确定时间间隔。然后，我们从样本中每个突发的固有色散的模拟值分布开始进行统计分析。结果。准直校正相关性似乎并不比各向同性等效相关性更分散。此外，单个伽马射线暴的分散程度明显低于整个样本。我们排除了（在 4.2 σ置信水平下）样本大小的差异作为可能的原因，从而证实了单个伽玛暴本质上比整个样本更不分散。对于具有可用信息的少数伽玛暴，没有发现固有色散与其他关键特性之间的相关性。结论。射流张角对分散的贡献是不相关的。此外，我们的结果证明，影响E p, i − L iso相关性的内在色散部分但不完全是由于不同伽玛暴的组装造成的。因此，我们得出结论，不同伽玛暴的存在显着影响了观察到的时间平均E p, i − L p, iso和E p, i − E iso相关性。
京公网安备 11010802027423号