Mid-infrared interferometry of 23 AGN tori: On the significance of polar-elongated emission
Mid-infrared interferometry of 23 AGN tori: On the significance of polar-elongated emission
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23 AGN环面的中红外干涉测量：论极拉长发射的意义
DOI：
10.1051/0004-6361/201527590
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
M. Schartmann
中科院分区：
文献类型：
--
作者：
N. L'opez;L. Burtscher;K. Tristram;K. Meisenheimer;M. Schartmann
上下文。利用中红外(MIR)干涉术对活动星系核进行了详细的高分辨率研究，发现有四个源的尘埃排放在极地方向拉长了几秒大小。
目标。利用MIR干涉测量法观测到的更大的、相干分析的活动星系核样本，我们的目标是在源的统计样本中识别拉长的中红外发射。更具体地说，我们希望确定是否确实存在较好的伸长方向，以及该方向是否与环状结构或极发射相一致。
方法：研究方法。通过将拉长的高斯模型与12微米的干涉数据进行拟合，我们研究了在MIR发射中检测拉长形状的意义。我们特别注意1)不均匀(u，v)覆盖造成的不确定性，2)测量中的典型误差，以及3)每个目标所达到的空间分辨率。
结果。从我们的23个源的样本中，我们能够在五个源中发现拉长的微秒尺度的MIR发射：三个类型2s，一个类型1i和一个类型1。其中四个源的拉长发射已经发表过；NGC5506是一个新的检测到的。观测到的轴比通常在2左右，所有拉长的源的12微米发射的位置角似乎总是更接近系统的极轴，而不是赤道轴。另外两个物体，NGC4507和MCG-5-23-16，具有合理的映射(u，v)覆盖和良好的信噪比，似乎具有较小的拉长12微米发射。
结论。我们的发现表明，显示拉长的中红外发射的源优先在极方向上扩展，这对环面模型设置了很强的约束，或者意味着环面和NLR/流出区必须被一起建模。特别是，用于SED拟合的模型也必须进行修订，以包括极地尘埃的排放。
Context. Detailed high resolution studies of AGN with mid-infrared (MIR) interferometry have revealed parsec-sized dust emission elongated in the polar direction in four sources.
Aims. Using a larger, coherently analyzed sample of AGN observed with MIR interferometry, we aim to identify elongated mid-infrared emission in a statistical sample of sources. More specifically we wish to determine if there is indeed a preferred direction of the elongation and whether this direction is consistent with a torus-like structure or with a polar emission.
Methods. We investigate the significance of the detection of an elongated shape in the MIR emission by fitting elongated Gaussian models to the interferometric data at 12 um. We pay special attention to 1) the uncertainties caused by an inhomogeneous (u,v) coverage, 2) the typical errors in the measurements and 3) the spatial resolution achieved for each object.
Results. From our sample of 23 sources we are able to find elongated parsec-scale MIR emission in five sources: three type 2s, one type 1i and one type 1. Elongated emission in four of these sources has been published before; NGC5506 is a new detection. The observed axis ratios are typically around 2 and the position angle of the 12 um emission for all the elongated sources seems to be always closer to the polar axis of the system than to the equatorial axis. Two other objects, NGC4507 and MCG-5-23-16 with a reasonably well mapped (u,v) coverage and good signal-to-noise ratios, appear to have a less elongated 12 um emission.
Conclusions. Our finding that sources showing elongated mid-infrared emission are preferentially extended in polar direction sets strong constraints on torus models or implies that both the torus and the NLR/outflow region have to be modeled together. Especially also models used for SED fitting will have to be revised to include emission from polar dust.
DOI：
10.1088/0004-637x/755/2/149
发表时间：
2012-06
期刊：
The Astrophysical Journal
影响因子：
--
作者：
S. Hoenig;M. Kishimoto;R. Antonucci;A. Marconi;M. Prieto;K. Tristram;Gerd Weigelt Ucsb;Mpifr;U. Firenze;Iac
通讯作者：
S. Hoenig;M. Kishimoto;R. Antonucci;A. Marconi;M. Prieto;K. Tristram;Gerd Weigelt Ucsb;Mpifr;U. Firenze;Iac
极地地区的尘埃是活动星系核红外发射的主要贡献者
DOI：
10.1088/0004-637x/771/2/87
发表时间：
2013
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Hönig;Kishimoto;Tristram
通讯作者：
Tristram