• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>PASJ: Publications of the Astronomical Society of Japan >Chandra and XMM-Newton observations of a group of galaxies, HCG 62
【24h】

Chandra and XMM-Newton observations of a group of galaxies, HCG 62

机译：钱德拉和XMM-牛顿对一组星系的观测，HCG 62

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

We present results from Chandra and XMM-Newton observations of a bright group of galaxies, HCG 62. There are two cavities at about 30" northeast and 20" southwest of the central galaxy in the Chandra image. The energy spectrum shows no significant change in the cavity compared with that in the surrounding region. The radial X-ray profile is described by the sum of the 3-beta components with core radii of about 2, 10, and 160 kpc. We studied the radial distributions of the temperature and the metal abundance with a joint spectral fit for both data; two temperatures were required in the inner r < 2' (36 kpc) region. A sharp drop of the temperature at r similar to 5' implies a gravitational mass density even lower than the gas density, suggesting that the gas may not be in hydrostatic equilibrium. The Fe and Si abundances are 1-2 solar at the center, and drop to about 0.1 solar at r similar to 10'. The O abundance is less than 0.5 solar, and shows a flatter profile. The observed metal distribution supports the view that iron and silicon are produced by type la supernova (SN Ia) in the central galaxy, while galactic winds by SN II have caused a wide distribution of oxygen. The supporting mechanism of the cavity is discussed. The pressure for the sum of electrons and the magnetic field is too low to displace the hot group gas, and the required pressure due to high-energy protons is nearly 700-times higher than the electron pressure. This leaves the origin of the cavities a puzzle; we also discuss other possible origins of the cavities.
机译：我们介绍了钱德拉和XMM-牛顿对一组明亮的星系HCG 62的观测结果。在钱德拉影像中，在中央星系东北约30“东北和西南约20”处有两个空腔。与周围区域相比，能谱显示腔体无明显变化。径向X射线轮廓由芯半径约为2、10和160 kpc的3-beta分量之和描述。我们研究了温度和金属丰度的径向分布，并结合了两个数据的光谱拟合。内部r <2'（36 kpc）区域需要两个温度。温度在r处急剧下降（类似于5'）意味着重力质量密度甚至低于气体密度，这表明气体可能未处于流体静力平衡状态。铁和硅的丰度在中心为1-2太阳，在r处下降到约0.1太阳，类似于10'。 O丰度小于0.5太阳光，并且显示出较平坦的轮廓。观察到的金属分布支持这样的观点，即铁和硅是由中央星系中的la超新星（SN Ia）类型产生的，而SN II的银河风造成了氧的广泛分布。讨论了空腔的支撑机理。电子和磁场之和的压力太低而无法置换热的族气体，并且由于高能质子所需要的压力比电子压力高近700倍。这使型腔的起源变得令人困惑。我们还将讨论腔的其他可能来源。

著录项

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