arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1703.04586astro-ph.GAastro-ph.COastro-ph.HE
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真正的Type 2 Seyfert NGC3147的NuSTAR视图

The NuSTAR view of the true Type 2 Seyfert NGC3147

Stefano Bianchi, Andrea Marinucci, Giorgio Matt, Riccardo Middei, Xavier Barcons, Loredana Bassani, Francisco J. Carrera, Fabio La Franca, Francesca Panessa

摘要:

我们提出了第一个NuSTAR观测一个“真正的”2型塞弗特星系。NGC 3147的3-40 keV X射线谱的特征在于简单的幂律,具有标准Γ~1.7和铁发射线,不需要任何高达~40 keV的其他成分。这些光谱特性,加上短至数周的时间尺度上的显著变化(如2014年雨燕监测活动所示),强烈支持该来源的清晰视线。另一种方案是强烈反对康普顿厚的源,需要特殊的几何配置,而大部分的立体角的来源是由高度电离的气体,其再处理的发射将占主导地位的观测光度填充。此外,在这种情况下,源的隐含内在X射线光度将远远大于其他光度代理预测的值,如[OIII]λ5007发射线的修正光度。因此,我们非常确信NGC 3147是一个真正的2型塞弗特星系,其本质特征是没有BLR。

英文摘要:

We present the first NuSTAR observation of a 'true' Type 2 Seyfert galaxy. The 3-40 keV X-ray spectrum of NGC3147 is characterised by a simple power-law, with a standard Γ~1.7 and an iron emission line, with no need for any further component up to ~40 keV. These spectral properties, together with significant variability on time-scales as short as weeks (as shown in a 2014 Swift monitoring campaign), strongly support an unobscured line-of-sight for this source. An alternative scenario in terms of a Compton-thick source is strongly disfavoured, requiring an exceptional geometrical configuration, whereas a large fraction of the solid angle to the source is filled by a highly ionised gas, whose reprocessed emission would dominate the observed luminosity. Moreover, in this scenario the implied intrinsic X-ray luminosity of the source would be much larger than the value predicted by other luminosity proxies, like the [OIII]λ5007 emission line extinction-corrected luminosity. Therefore, we confirm with high confidence that NGC3147 is a true Type 2 Seyfert galaxy, intrinsically characterised by the absence of a BLR.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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