在NGC 1068的活跃核中的中央尘土
W Jaffe1, K Meisenheimer, H J A Röttgering
1Leiden Observatory, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands. jaffe@strw.leidenuniv.nl
Nature
|May 7, 2004
概括
介面测量中红外观测首次在空间上解析了活跃银河系核 (AGN) 中的尘土. 这种结构对于了解AGN外观至关重要,需要持续的能量输入才能保持稳定.
科学领域:
- 天文学 天文学
- 天体物理学 天体物理学
- 银河系的进化 银河系的进化
背景情况:
- 活跃的星系核 (AGN) 呈现出被归因于物质积聚到超大质量黑洞上的能量现象.
- 人们普遍认为,AGN的观测外观受到方向效应的影响,环核尘埃遮蔽了中心区域.
- 以前的间接证据表明,这些尘埃云的分布是帕塞克大小的圆柱状分布,但直接的分辨率仍然难以捉摸.
研究的目的:
- 为了在空间上解析围绕活跃银河系核的中心引擎的帕塞克大小的尘埃结构.
- 为AGN中拟议的圆柱体模型提供直接的观察证据.
- 调查已解决的尘埃结构的物理条件和稳定性.
主要方法:
- 使用了干扰度的中红外观测.
- 针对NGC 1068星系进行高分辨率成像.
- 分析了尘埃结构的空间分布和温度.
主要成果:
- 在NGC 1068中一个更热的中心区域周围的圆柱状结构 (厚度2.1个百分比,直径3.4个百分比) 中,空间分辨率高的热 (320K) 尘埃.
- 提供了AGN中环核尘埃结构的第一个直接的,分辨率高的图像.
- 观察到的尘埃配置在短时间内是动态不稳定的.
结论:
- 在NGC 1068中的尘土的直接分辨率证实了它在塑造AGN观测中的作用.
- 观察到的尘埃结构的不稳定性意味着与AGN共存的连续能量输入机制.
- 需要进一步的研究来确定这种动能输入的来源及其对AGN演变的影响.
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