论文标题
在伽马射线爆发的两部分喷气机模型中的同步加速器自compton排放
Synchrotron Self-Compton Emission in the Two-Component Jet Model for Gamma-Ray Bursts
论文作者
论文摘要
伽马射线爆发（GRB）是由相对论喷射引起的高能光子（及时排放）的强烈爆发。排放后，从无线电到非常高的能量（VHE）伽马射线的多波长余气持续了几天多。 In the past three years, the VHE gamma-ray photons from four GRBs (GRBs 180720B, 190114C, 190829A and 201216C) were detected by ground-based Imaging Atmospheric Cherenkov Telescopes, such as the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes and the High Energy Stereoscopic System (H.E.S.S.).其中一个是GRB 190829a，具有一些特殊的特征，即在X射线和光条上显示出$ 1.4 \ times10^3 $ s的可观峰，并被归类为低亮度GRB。以前，我们提出了一个两组式喷气型号，该模型具有“窄喷'”，其初始开口$θ_0= 0.015 $ rad and Bumbolk lorentz factor $γ_0= 350 $和$θ_0= 0.1 $ rad和$γ_0= 20 $。狭窄的射流解释了早期的X射线和光学排放以及显然小的各向同性γ射线射线和峰值能量。此外，X射线和无线电（1.3和15.5 GHz）的余气是从宽喷射中排放的。在这里，我们通过Synchrotron Self-Compton（SSC）发射计算VHE伽马射线通量。我们的两个组成射流模型很好地解释了GRB 190829a的多波长余星。我们两组式射流的余辉排放也与GRBS 180720b，190114c和201216c的观察结果一致，当时射流轴上。此外，我们讨论了Cherenkov望远镜阵列（CTA）的外轴孤儿的可检测性。
Gamma-ray bursts (GRBs) are intense bursts of high-energy photons (prompt emissions) caused by relativistic jets. After the emissions, multi-wavelength afterglows, from radio to very-high-energy (VHE) gamma-ray, last for more than a few days. In the past three years, the VHE gamma-ray photons from four GRBs (GRBs 180720B, 190114C, 190829A and 201216C) were detected by ground-based Imaging Atmospheric Cherenkov Telescopes, such as the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes and the High Energy Stereoscopic System (H.E.S.S.). One of them, GRB 190829A, had some peculiar features of showing achromatic peaks in X-ray and optical bands at $1.4\times10^3$ s and being classified as low-luminosity GRBs. Previously, we proposed a two-component jet model, which has `narrow jet' with a small initial opening half-angle $θ_0=0.015$ rad and large bulk Lorentz factor $Γ_0=350$, and `wide jet' with $θ_0=0.1$ rad and $Γ_0=20$. The narrow jet explained the early X-ray and optical emissions and apparently small isotropic gamma-ray energy and peak energy in the off-axis viewing case. Furthermore, the late X-ray and radio (1.3 and 15.5 GHz) afterglows were emitted from the wide jet. Here, we calculate the VHE gamma-ray flux by the synchrotron self-Compton (SSC) emission. The multi-wavelength afterglows of GRB 190829A including the VHE gamma-ray emission are well explained by our two-component jet model. The afterglow emissions from our two-component jet are also consistent with the observational results of GRBs 180720B, 190114C and 201216C, when the jets are viewed on-axis. Furthermore, we discuss the detectability of off-axis orphan afterglows by the Cherenkov Telescope Array (CTA).
