Dust energy balance study of two edge-on spiral galaxies in the Herschel-ATLAS survey
Dust energy balance study of two edge-on spiral galaxies in the Herschel-ATLAS survey
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赫歇尔-阿特拉斯巡天中两个边缘螺旋星系的尘埃能量平衡研究
DOI：
10.1093/mnras/stv1104
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发表时间：
2015
影响因子：
4.8
通讯作者：
De Geyter G
中科院分区：
文献类型：
--
作者：
De Geyter G
星系中的星际尘埃可以通过它对恒星光的消光作用或通过它在红外波长下的热发射来追踪。最近对附近几个边缘上星系的辐射传输研究发现，尘埃能量平衡中存在明显的不一致：成功解释光学消光的辐射传输模型将观测到的通量低估了平均3倍。我们研究了赫歇尔空间天文台在H-ATLAS观测框架下观测到的两个边缘上螺旋星系IC-4225和NGC-5166的尘埃能量平衡。我们从受光学数据约束的模型开始，并将其扩展到构建我们星系的整个光谱能量分布。随后将这些预测值与观测到的远红外通量进行比较。我们发现，将年轻的恒星群体包括在模型中是必要的，因为它在尘埃颗粒的加热中起着不可忽视的作用。虽然这两个星系的建模方法几乎相同，但我们发现了两个截然不同的结果。正如在其他边缘螺旋星系中经常看到的那样，我们的辐射传输模型IC-4225的远红外辐射将观测到的通量低估了大约3倍。另一方面，对于NGC-5166，我们发现无论是预测的光谱能量分布还是模拟的图像都与观测结果吻合得特别好。我们探索了造成这种差异的可能原因，并得出结论，单一的机制不太可能是螺旋星系中尘埃能量平衡问题的原因。我们讨论了可以考虑的不同方法，以便对这种差异的根源得出决定性的答案。
Interstellar dust in galaxies can be traced either through its extinction effects on the star light or through its thermal emission at infrared wavelengths. Recent radiative transfer studies of several nearby edge-on galaxies have found an apparent inconsistency in the dust energy balance: the radiative transfer models that successfully explain the optical extinction underestimate the observed fluxes by an average factor of 3. We investigate the dust energy balance for IC 4225 and NGC 5166, two edge-on spiral galaxies observed by theHerschel Space Observatoryin the frame of the H-ATLAS survey. We start from models which were constrained from optical data and extend them to construct the entire spectral energy distribution of our galaxies. These predicted values are subsequently compared to the observed far-infrared fluxes. We find that including a young stellar population in the modelling is necessary as it plays a non-negligible part in the heating of the dust grains. While the modelling approach for both galaxies is nearly identical, we find two very different results. As is often seen in other edge-on spiral galaxies, the far-infrared emission of our radiative transfer model of IC 4225 underestimates the observed fluxes by a factor of about 3. For NGC 5166 on the other hand, we find that both the predicted spectral energy distribution as well as the simulated images match the observations particularly well. We explore possible reasons for this difference and conclude that it is unlikely that one single mechanism is the cause of the dust energy balance problem in spiral galaxies. We discuss the different approaches that can be considered in order to get a conclusive answer on the origin this discrepancy.
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我们应该相信紫外毫米星系光谱能量分布模型的结果吗？
DOI：
--
发表时间：
2014
期刊：
影响因子：
--
作者：
C. Hayward;Daniel J B Smith
通讯作者：
Daniel J B Smith
影响因子：
6.5
作者：
B. Groves;M. Dopita;Ralph Sutherland Mpa;Garching;H Germany;Rsaa;Anu;Australia.
通讯作者：
B. Groves;M. Dopita;Ralph Sutherland Mpa;Garching;H Germany;Rsaa;Anu;Australia.
DOI：
10.1046/j.1365-8711.2003.06770.x
发表时间：
2003-04
影响因子：
4.8
作者：
M. Baes;J. Davies;H. Dejonghe;S. Sabatini;S. Roberts;R. Evans;S. Linder;Rodney M. Smith;W. D. Blok
通讯作者：
M. Baes;J. Davies;H. Dejonghe;S. Sabatini;S. Roberts;R. Evans;S. Linder;Rodney M. Smith;W. D. Blok
银河亚毫米尘埃发射率是否被低估
影响因子：
6.5
作者：
K. Dasyra;E. Xilouris;A. Misiriotis;N. Kylafis
通讯作者：
N. Kylafis
VLT/VIMOS 对隐匿星系对的观测：红移和有效消光曲线
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
B. Holwerda;T. Böker;J. Dalcanton;W. Keel;R. D. Jong
通讯作者：
R. D. Jong