论文标题
Z229-15的灰尘混响映射
Dust Reverberation Mapping of Z229-15
论文作者
论文摘要
我们报告了Seyfert 1 Galaxy Z229-15上的灰尘混响映射（DRM）的结果，Z = 0.0273。在2017年7月至2018年12月的B，V，J，H和KS频段中，准单相中的光度观察总共获得了48个时期。每个时期的B和V频段之间计算出的光谱指数（α）用于校正红外光曲线中存在的吸积盘（AD）分量。观察到的α范围在-0.99至1.03之间。使用互相关函数分析，我们发现光学V和AD校正的J，H和KS光曲线之间的大幅度延迟。源的其余框架中的滞后为12.52（+10.00/-9.55）天（V和J之间），15.63（+5.05/-5.11）天（V和H之间）和20.36（+5.82/-5.68）天（V和KS之间）。鉴于较大的误差线，这些滞后是彼此一致的。但是，考虑到V和KS频段之间的滞后以表示尘埃的内边缘，Z229-15中的圆环位于与中央电离连续体的0.017 PC的距离。这比DRM已知的半径光度（R-L）关系所期望的要小。使用常数α= 0.1来解释AD分量，如DRM中通常所做的那样，推导的半径（0.025 PC）位于预期的R-L关系附近。然而，随着电离连续体的α随源的通量变化而变化，DRM中常数α的使用被散布。
We report results of the dust reverberation mapping (DRM) on the Seyfert 1 galaxy Z229-15 at z = 0.0273. Quasi-simultaneous photometric observations for a total of 48 epochs were acquired during the period 2017 July to 2018 December in B, V, J, H and Ks bands. The calculated spectral index (α) between B and V bands for each epoch was used to correct for the accretion disk (AD) component present in the infrared light curves. The observed α ranges between -0.99 and 1.03. Using cross correlation function analysis we found significant time delays between the optical V and the AD corrected J, H and Ks light curves. The lags in the rest frame of the source are 12.52 (+10.00/-9.55) days (between V and J), 15.63 (+5.05/-5.11) days (between V and H) and 20.36 (+5.82/-5.68) days (between V and Ks). Given the large error bars, these lags are consistent with each other. However, considering the lag between V and Ks bands to represent the inner edge of the dust torus, the torus in Z229-15 lies at a distance of 0.017 pc from the central ionizing continuum. This is smaller than that expected from the radius luminosity (R-L) relationship known from DRM. Using a constant α = 0.1 to account for the AD component, as is normally done in DRM, the deduced radius (0.025 pc) lies close to the expected R-L relation. However, usage of constant α in DRM is disfavoured as the α of the ionizing continuum changes with the flux of the source.
