A systematic study of Galactic infrared bubbles along the Galactic plane with AKARI and Herschel
A systematic study of Galactic infrared bubbles along the Galactic plane with AKARI and Herschel
复制标题
与 AKARI 和 Herschel 一起系统研究沿银河平面的银河红外气泡
DOI：
10.1093/pasj/psy126
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发表时间：
2019
影响因子：
2.3
通讯作者：
F.
中科院分区：
文献类型：
--
作者：
Hanaoka;M.;Kaneda;H.;Suzuki;T.;Kokusho;T.;Oyabu;S.;Ishihara;D.;Kohno;M.;Furuta;T.;Tsuchikawa;T.;& Saito;F.
银河系红外（IR）气泡，在中红外波长具有壳状结构，已知在其中心附近包含大质量恒星。银河系内部的红外气泡（|L| ≤ 65°，|B| ≤ 1°）的大质量恒星已经被很好地研究，以了解大质量星星的形成机制。本研究将研究范围扩大到整个银道面（0° ≤l< 360°，|B| ≤ 5°），使用AKARI全天巡天数据。我们将我们的研究限制在角半径>1′的大气泡上，以可靠地识别和表征它们。对于总共247个红外气泡，我们根据Y. Hattori等（，PASJ，68，37）。我们还使用AKARI和Herschel测光数据创建了它们的光谱能量分布，并使用尘埃模型对其进行分解，以获得总的IR光度和每个尘埃成分的光度，即，多环芳烃（PAH）、暖尘和冷尘。结果，我们发现，有系统的差异之间的内部和外部的银河系区域的气泡的红外特性。总的红外光度较低的外银河系区域，而没有系统的差异之间的壳半径的范围内和外银河系区域。更多的红外气泡倾向于观察到破碎的气泡，而不是封闭的和PAH排放的分数光度显着更高的外银河系地区。我们讨论了这些结果对大质量恒星和与银河系红外气泡相关的星际环境的影响。
Galactic infrared (IR) bubbles, which have shell-like structures in the mid-IR wavelengths, are known to contain massive stars near their centers. Infrared bubbles in inner Galactic regions (|l| ≤ 65°, |b| ≤ 1°) have so far been studied well to understand the massive star formation mechanisms. In this study, we expand the research area to the whole Galactic plane (0° ≤l< 360°, |b| ≤ 5°), using the AKARI all-sky survey data. We limit our study to large bubbles with angular radii of >1′ to reliably identify and characterize them. For the 247 IR bubbles in total, we derived the radii and the covering fractions of the shells, based on the method developed by Y. Hattori et al. (, PASJ, 68, 37). We also created their spectral energy distributions, using the AKARI and Herschel photometric data, and decomposed them with a dust model to obtain the total IR luminosity and the luminosity of each dust component, i.e., polycyclic aromatic hydrocarbons (PAHs), warm dust, and cold dust. As a result, we find that there are systematic differences in the IR properties of the bubbles between the inner and outer Galactic regions. The total IR luminosities are lower in outer Galactic regions, while there is no systematic difference in the range of the shell radii between inner and outer Galactic regions. More IR bubbles tend to be observed as broken bubbles rather than closed ones and the fractional luminosities of the PAH emission are significantly higher in outer Galactic regions. We discuss the implications of these results for the massive stars and the interstellar environments associated with the Galactic IR bubbles.