Multi-Zone Blazar Modelling

多区域 Blazar 建模

• 批准号: 1835472
• 金额: --
• 依托单位: University of Bath
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1835472
• 关键词: Multi; Zone; Blazar; Modelling

Blazars are a relativistic gas outflow associated with Active Galactic Nucleiand with the characteristic of being extremely high in luminosity. They areknown to be related to galaxy evolution and to cosmic rays and neutrinos.Because of this, and their extreme physics, they are in a position ofimportance among high-energy astrophysical sources. Due to the Fermi X-rayand Fermi gamma-ray satellites, the amount of data available for this kindof objects has increased significantly, and with that, the variety ofresearch that can be done.Until now, modelling of blazars has been done mostly using simplified"one-zone" models, assuming a single dominant emission site, which alreadycan explain some of the processes that occur in blazars. But because of theincrease in computational power and numerical techniques, we are now ableto move beyond those models to more complex models, multi-zone models inparticular, capable of describing recent high-quality data.Early versions of such new models are already demonstrating an improved fitto the observational data. But they separate leptonic and hadronic modelsfor the dominant emitting particle species, and the study of the continuumand the variability. Our objective is to merge numerically thedifferent approaches.Research will start with literature study and numerically reproducing ofpast results through a radiation code developed in-house. After that we willtest the effect of geometry and that of extending emission to multipleanalytically modeled discrete zones and interacting emitting shells.We will continue by simulating outflows in one and two dimensions, movingfrom analytically to numerically computed dynamics, and by graduallyincreasing the complexity by including more kinds of particles and processes.

耀变体是与活动星系核有关的相对论性气体外流，具有极高的光度。众所周知，它们与星系演化、宇宙射线和中微子有关。正因为如此，再加上它们极端的物理性质，它们在高能天体物理源中占有重要地位。由于费米X射线和费米伽马射线卫星的出现，这类天体的可用数据量显著增加，因此可以进行的研究也随之增加。到目前为止，耀变体的建模主要是使用简化的“单区”模型，假设一个主要的发射点，这已经可以解释耀变体中发生的一些过程。但由于计算能力和数值技术的提高，我们现在能够超越这些模型，转向更复杂的模型，特别是多区域模型，能够描述最近的高质量数据。这种新模型的早期版本已经证明了对观测数据的更好的拟合。但是他们把主导发射粒子种类的轻子和强子模型分开，并把连续性和可变性的研究分开。我们的目标是合并数值不同的方法。研究将开始与文献研究和数值再现过去的结果，通过辐射代码开发的内部。之后，我们将测试几何形状的影响，以及将发射扩展到多个解析建模的离散区域和相互作用的发射壳层的影响。我们将继续模拟一维和二维的外流，从解析转向数值计算动力学，并通过包括更多种类的粒子和过程来逐渐增加复杂性。