• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Thermal and non-thermal contributions to the X-ray spectrum of Large Magellanic Cloud supernova remnants.
【24h】

Thermal and non-thermal contributions to the X-ray spectrum of Large Magellanic Cloud supernova remnants.

机译：大麦哲伦星云超新星残骸的X射线光谱的热和非热贡献。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The study of supernovae and the expanding remnants that form after the explosion is important to understanding star formation and the distribution of elements in the interstellar medium (ISM). This work examines the X-ray spectrum of 14 LMC remnants: three new Chandra observations, and eleven archival ASCA observations. The plasma that is responsible for the X-ray emission is heated by a shock wave created by the supernova explosion that expands into the ISM. The picture is further complicated by a reverse shock that is created at the interface between the ISM and the material ejected from the star by the explosion. Non-equilibrium ionization (NEI) models are used to describe the thermal contributions to the spectrum. Existing models assume that hydrogen and helium are the sole source of electrons in the plasma. A new NEI model is introduced and tested which accounts for the overabundance of heavy elements in the remnant ejecta and their contribution to the electron density. This is a plane-parallel shock model that can account for non-Coulomb heating at the shock front and uses shock velocity as a parameter rather than shock temperature. Hard, non-thermal tails that are well described by a power law have been observed in the X-ray spectra of several remnants. Synchrotron radiation observed in the radio regime for low energy electrons can be extrapolated to X-ray energies to account for high energy (>1 TeV) electrons. By combining X-ray data with radio observation parameters we can constrain the maximum energies of the shock-accelerated electrons in the supernovae. None of the remnants in this study have a maximum energy above 100 TeV. SNR 0534-69.9 and SNR 0548-70.4 spectra show middle-aged remnants with significant contributions from the ejecta inside the outer shell. The ejecta detection allowed the classification of a Type Ia progenitor for both. The SNR 0453-68.5 observation indicates a core-collapse explosion due to the presence of a pulsar wind nebula.
机译：对超新星和爆炸后形成的膨胀残余物的研究对于理解恒星形成和星际介质中元素的分布（ISM）具有重要意义。这项工作检查了14个LMC残余物的X射线光谱：三个新的 Chandra 观测值和十一个ASCA归档观测值。负责X射线发射的等离子体被超新星爆炸产生的冲击波加热，该冲击波扩展到ISM中。在ISM和爆炸爆炸从恒星弹出的物质之间的界面处产生的反向冲击使情况进一步复杂化。非平衡电离（NEI）模型用于描述对光谱的热贡献。现有模型假定氢和氦是等离子体中电子的唯一来源。引入并测试了一种新的NEI模型，该模型说明了剩余射流中重元素的丰度及其对电子密度的贡献。这是一个平面平行的冲击模型，可以解释在冲击前沿的非库仑加热，并且将冲击速度作为参数而不是冲击温度。在数个残留物的X射线光谱中观察到了幂律很好地描述的坚硬，非热的尾部。可以将在无线电体制下观察到的低能电子的同步加速器辐射外推至X射线能量，以解释高能（> 1 TeV）电子。通过将X射线数据与射电观测参数结合起来，我们可以限制超新星中激波加速电子的最大能量。在这项研究中，没有任何残留物的最大能量高于100 TeV。 SNR 0534-69.9和SNR 0548-70.4光谱显示中年残余物，其原因是外壳内部的喷出物。排出物的检测允许对两者的Ia型祖细胞进行分类。 SNR 0453-68.5的观测结果表明，由于存在脉冲星云，星核崩溃。

著录项

  • 作者

    Hendrick, Sean Patrick.;

  • 作者单位

    North Carolina State University.;

  • 授予单位 North Carolina State University.;
  • 学科 Physics Astronomy and Astrophysics.
  • 学位 Ph.D.
  • 年度 2003
  • 页码 176 p.
  • 总页数 176
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 天文学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号