The multiwavelength variability of 3C 273
The multiwavelength variability of 3C 273
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DOI：
10.1051/0004-6361:200809947
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发表时间：
2008-05
影响因子：
6.5
通讯作者：
S. Soldi;M. Turler;S. Paltani;H. Aller;M. Aller;G. Burki;M. Chernyakova;A. Lahteenmaki;I. McHardy;E. I. Robson;R. Staubert;M. Tornikoski;R. Walter;T. J. C. Isdc;G. Observatory;U. Michigan;Dias;Metsahovi Radio Observatory;U. Southampton;UK Astronomy Technology Centre;Iaa Tubingen
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作者：
S. Soldi;M. Turler;S. Paltani;H. Aller;M. Aller;G. Burki;M. Chernyakova;A. Lahteenmaki;I. McHardy;E. I. Robson;R. Staubert;M. Tornikoski;R. Walter;T. J. C. Isdc;G. Observatory;U. Michigan;Dias;Metsahovi Radio Observatory;U. Southampton;UK Astronomy Technology Centre;Iaa Tubingen
目标。我们介绍了 ISDC 托管的 3C 273 数据库的更新，其中包含过去 10 年从无线电到伽马射线观测的数据。我们使用这个大数据集来研究这个类星体的多波长特性，特别是关注它的变异行为。方法。我们研究整个宽带光谱的变化幅度和最大变化时间尺度，并将不同波段的光变曲线（特别是 X 射线）关联起来，以寻找不同能量发射之间可能的联系。结果。 3C 273 显示了所有频率的变化，幅度和时间尺度强烈依赖于能量并且是不同发射机制的特征。 X 射线波段的可变性特性意味着存在两个单独的分量（可能是类 Seyfert 和类耀变体）或至少两个具有不同定时特性的参数，以解释低于和高于 ∼20 keV 的 X 射线发射。主要的硬 X 射线发射很可能不是由喷射中的冲击波加速的电子造成的，因为它们的变化与耀斑的毫米级发射无关，但似乎与光学的长时标变化有关。该光学组件与来自射流底部的光学薄同步加速器辐射一致，并且硬 X 射线将由相同的电子群通过逆康普顿过程（SSC 和/或 EC）产生。我们证明，这种同步加速器组件从光学领域延伸到近红外领域，在近红外领域，它与我们发现距离紫外线源约 1 光年以内的加热尘埃的发射混合在一起。
Aims. We present an update of the 3C 273’s database hosted by the ISDC, completed with data from radio to gamma-ray observations over the last 10 years. We use this large data set to study the multiwavelength properties of this quasar, especially focussing on its variability behaviour. Methods. We study the amplitude of the variations and the maximum variability time scales across the broad-band spectrum and correlate the light curves in different bands, specifically with the X-rays, to search for possible connections between the emission at different energies. Results. 3C 273 shows variability at all frequencies, with amplitudes and time scales strongly depending on the energy and being the signatures of the different emission mechanisms. The variability properties of the X-ray band imply the presence of either two separate components (possibly a Seyfert-like and a blazar-like) or at least two parameters with distinct timing properties to account for the X-ray emission below and above ∼20 keV. The dominant hard X-ray emission is most probably not due to electrons accelerated by the shock waves in the jet as their variability does not correlate with the flaring millimeter emission, but seems to be associated to long-timescale variations in the optical. This optical component is consistent with being optically thin synchrotron radiation from the base of the jet and the hard X-rays would be produced through inverse Compton processes (SSC and/or EC) by the same electron population. We show evidence that this synchrotron component extends from the optical to the near-infrared domain, where it is blended by emission of heated dust that we find to be located within about 1 light-year from the ultraviolet source.