The origin of the high energy gamma-ray emission from the Crab nebula - clues from the spatial extension and energy spectrum

蟹状星云高能伽马射线发射的起源——空间延伸和能谱的线索

基本信息

批准号：
360780919
负责人：
Professor Dr. Dieter Horns
金额：
--
依托单位：
Institut für Experimentalphysik
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2017
资助国家：
德国
起止时间：
2016-12-31 至 2020-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/360780919?language=en
关键词：
origin energy gamma ray emission

项目摘要

The Crab nebula is the remnant of a historical supernova from the year 1054. The nebula has been observed in great detail at every accessible energy from radio frequency to gamma-rays at 100 TeV. Most of the observed radiation is synchrotron emission of energetic particles originating in the steady pulsar wind emitted by the Crab pulsar. The energetic particles are deflected by the magnetic field (of largely unknown structure and strength) permeating the nebula. With recent observations of the nebula with Fermi-LAT we have been able to demonstrate that the nebula can be spatially resolved at energies above a few GeV. In this project, we will analyse both the data taken with Fermi-LAT as well as with the H.E.S.S. telescopes in order to determine the energy dependent size of the gamma-nebula. Jointly with the observed integrated spectrum, we will be able to spatially characterize the underlying electron energy distribution. The required assumption is an inverse Compton origin of the gamma-radiation,i.e., energetic electrons up-scatter lower energy photon fields present in the nebula. Given the detailed observations, we will refine the available radiation field estimates to include the emission from the dusty plasma at the boundary of the synchrotron nebula. Finally, we will estimate the magnetic field and its large-scale structure present in the nebula using our estimate of the spatial and spectral distribution of particles. In order to exclude that the results are influenced by additional radiative components at gamma-rays, we will study as an alternative non-thermal Bremsstrahlung emitted from the dense regions of the nebula. The result of the study will be an in-depth understanding of the energy dependent spatial distribution of electrons in the nebula and consequently will be prepared to answer the question on the origin of the gamma-ray emission of the Crab nebula.

螃蟹星云是1054年以来历史上新星的残留物。在从射频到100 TEV处的每一个可访问的能量，在每一个可访问的能量上都非常详细地观察到了星云。观察到的大多数辐射是源自蟹脉冲发出的稳定脉冲风中的能量颗粒的同步发射。能量颗粒被磁场（在很大程度上未知的结构和强度）中偏转，并渗入星云。通过最近对暗星云的观察，我们已经能够证明，在少数GEV以上的能量上可以在空间上解析星云。在这个项目中，我们将使用费米 - 拉特（Fermi-Lat）以及H.E.S.S.进行分析数据。望远镜以确定γ-内比拉的能量依赖性尺寸。与观察到的集成光谱共同，我们将能够在空间上表征基础电子能量分布。所需的假设是伽马辐射的反向康普顿起源，即，在星云中存在的降级较低的能量光子场。鉴于详细的观察结果，我们将完善可用的辐射场估计值，包括在同步基因星云的边界处发出的灰尘等离子体的发射。最后，我们将使用我们对颗粒的空间和光谱分布的估计来估计磁场及其大规模结构。为了排除结果受伽马射线的额外辐射成分的影响，我们将作为从星云的致密区域散发出来的替代性非热bremsstrahlung。该研究的结果将是对虚星中电子的能量依赖的空间分布的深入了解，因此，将准备回答有关蟹状星云的伽马射线发射起源的问题。