权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Emission Mechanism of Carbonaceous Interstellar and Circumstellar Dusts

碳质星际和星周尘埃的发射机制

基本信息

批准号：
01540217
负责人：
SAKATA Akira
金额：
$ 0.83万
依托单位：
The University of ElectroーCommunications
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

项目摘要

We have shown in a previous paper that oxidized f-QCC (Filmy Quenched Carbonaceous Composite) has absorption features that correspond to that of the interstellar 3.3, 3.4, 6.2, 7.7, 8.6, and 11.3mum mnission features. Here we present new laboratory data showing that oxidized f-QCC, after heating to 500^ﾟC, has a 3.29 mum absorption feature that matches precisely the wavelength of the 3.29mum interstellar emission feature. In addition, the width of the fーQCC feature is close to that of the 3.29mum emission feature observed in NGC 7027, Orion, and IRAS 21282+5050. Laboratory spectra of polycyclic hydrocarbons (PAHs) were also obtained, and comparison of the fーQCC and PAH absorption opectra to that of the 3.29mum emission feature indicates the fーQCC provides much better match. We therefore suggest that fーQCC is representative of the class of material giving rise to the emission features in the interstellar medium.A red excess emission were observed in 12 objects among 24 reflection nebula by Witt and Boroson (1990). The emission spectra were single broad features peaked at 650-700nm with about 130nm of FWHM. Witt and Boroson attributed them to the fluorescence of hydrogenated amorphous carbon dusts. We collected QCCs on a substrate at a temperature lower than room temperature. The QCCs were mixture of low molecular weight chemical species such as molecules and radicals. They emit fluorescence under UV irradiation. The spectra of fluorescence of QCCs agreed well to the observed red excess emissions.In order to analyze an IR spectrum of interstellar and circumstellar dust, it is necessary to measure an emission spectrum of a candidate dust material. We examined a simple method for IR emission measurement using a sample compartment emission accessory, made by Connecticut Instrument U.S.A. We achieved a test measurement with the accessory, and obtained a preliminary result.

我们已经表明，在以前的论文中，氧化的f-QCC（薄膜淬火碳复合材料）的吸收功能，对应于星际3.3，3.4，6.2，7.7，8.6，和11.3 μ m的发射功能。在这里，我们提出了新的实验室数据显示，氧化的f-QCC，加热到500 μ C后，有一个3.29 μ m的吸收功能，精确匹配的波长的3.29 μ m星际发射功能。此外，f QCC特征的宽度接近于在NGC 7027、猎户座和IRAS 21282+5050中观测到的3.29 μ m发射特征。实验室光谱的多环烃（PAH）也得到了，和比较的f QCC和PAH的吸收光谱的3.29 μ m的发射特征表明，f QCC提供了更好的匹配。Witt和Boroson（1990）在24个反射星云中观测到12个天体的红色过量发射。发射光谱为单一的宽谱特征，峰值在650- 700 nm，半高宽约130 nm。Witt和Boroson将其归因于氢化无定形碳粉尘的荧光。我们在低于室温的温度下在衬底上收集QCC。QCC是分子和自由基等低分子量化学物质的混合物。它们在紫外线照射下发出荧光。QCC的荧光光谱与观测到的红色过量发射相吻合。为了分析星际和星周尘埃的红外光谱，有必要测量候选尘埃物质的发射光谱。我们研究了一种使用美国康涅狄格仪器公司的样品室发射附件进行红外发射测量的简单方法。我们用该附件进行了试验测量，得到了初步结果。