首页> 外文OA文献 >Polycyclic Aromatic Hydrocarbons and Crystalline Silicates in the Bipolar Post-Asymptotic Giant Branch Star IRAS 16279-4757
【2h】

Polycyclic Aromatic Hydrocarbons and Crystalline Silicates in the Bipolar Post-Asymptotic Giant Branch Star IRAS 16279-4757

机译:双极后渐近巨分支星IRAS 16279-4757中的多环芳烃和结晶硅酸盐

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

IRAS 16279-4757 belongs to a group of post-asymptotic giant branch (post-AGB) stars showing both polycyclic aromatic hydrocarbon (PAH) bands and crystalline silicates. We present mid-infrared images that resolve the object for the first time. The morphology is similar to that of the ``Red Rectangle'' (HD 44179), the prototype object with PAHs and crystalline silicates. A two-component model and images suggest a dense oxygen-rich torus, an inner, low-density, carbon-rich region, and a carbon-rich bipolar outflow. The PAH bands are enhanced at the outflow, while the continuum emission is concentrated toward the center. Our findings support the suggestion that mixed chemistry and morphology are closely related. We discuss the Infrared Space Observatory Short-Wavelength Spectrometer (ISO SWS) spectra of IRAS 16279-4757. Several bands in the ISO SWS spectrum show a match with anorthite: this would be the first detection of this mineral outside the solar system. Compared to HD 44179, the shapes of PAH bands are closer to those of planetary nebulae, possibly related to a population of small PAHs present in HD 44179 but absent around IRAS 16279-4757. Detailed examination of the spectra shows the individual character of these two objects. The comparison suggests that the torus found in IRAS 16279-4757 may have formed more recently than that in HD 44179.
机译:IRAS 16279-4757属于一组渐近后巨星(后AGB)星,既显示多环芳烃(PAH)带,又显示结晶硅酸盐。我们展示了首次解析物体的中红外图像。形态类似于``红色矩形''(HD 44179),它是带有PAH和结晶硅酸盐的原型物体。由两部分组成的模型和图像显示出致密的富氧环面,内部,低密度,富碳区域和富碳双极流出。 PAH谱带在流出时增强,而连续谱发射则集中向中心。我们的发现支持混合化学和形态密切相关的建议。我们讨论了IRAS 16279-4757的红外空间天文台短波光谱仪(ISO SWS)光谱。 ISO SWS光谱中的几个波段显示出与钙长石匹配:这将是在太阳系之外首次检测到这种矿物。与HD 44179相比,PAH带的形状更接近行星状星云,可能与HD 44179中存在但在IRAS 16279-4757周围不存在的小型PAH数量有关。光谱的详细检查显示了这两个对象的个性。比较表明,在IRAS 16279-4757中发现的圆环可能比在HD 44179中形成的圆环更近。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
代理获取

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