标题： NGC 1068星系核中的非开普勒旋转：大量吸积盘的证据？ 显示英文标题

标题： Non-Keplerian rotation in the nucleus of NGC 1068: evidence for a massive accretion disk?

摘要： 塞弗特星系 NGC 1068 的核心被认为宿主一个超大质量黑洞。存在一个大质量中心天体的证据由水脉泽发射提供，这种发射在天空中显示出线性模式，暗示了一个旋转盘的存在。通过推导出的旋转曲线的下降形状进一步加强了旋转盘假设。来自 NGC 4258 的类似脉泽发射已经导致了对中心黑洞质量的一个可靠估计，因为在这种情况下的旋转曲线是开普勒式的。对于 NGC 1068 来说，由水脉泽追踪到的旋转曲线是非开普勒式的。在这篇文章中，我们通过自引力吸积盘模型对 NGC 1068 的非开普勒旋转提供了解释。我们对现有数据进行了良好的拟合，并推导出了黑洞质量 M_{bh}=(8.0\pm 0.3) 10^6M_{太阳}。由此得到的盘质量与黑洞质量相当。作为我们拟合程序的一个有趣副产品，我们能够估算粘度参数，结果为\alpha \approx 10^{-2}，这与一些理论预期一致。 显示英文摘要

摘要： The nucleus of the Seyfert galaxy NGC 1068 is believed to host a supermassive black hole. Evidence for the presence of a massive central object is provided by water maser emission, which displays a linear pattern in the sky, suggestive of a rotating disk. The rotating disk hypothesis is further strengthened by the declining shape of the derived rotation curve. Similar maser emission from NGC 4258 has led to a reliable estimate of the mass of the central black hole, because in this case the rotation curve is Keplerian. In the case of NGC 1068 the rotation curve traced by the water maser is non-Keplerian. In this paper we provide an interpretation of the non-Keplerian rotation in NGC 1068 by means of a self-gravitating accretion disk model. We obtain a good fit to the available data and derive a black hole mass M_{bh}=(8.0\pm 0.3) 10^6M_{sun}. The resulting disk mass is comparable to the black hole mass. As an interesting by-product of our fitting procedure, we are able to estimate the viscosity parameter, which turns out to be \alpha\approx 10^{-2}, in line with some theoretical expectations.