论文标题
最长的延迟：14.5年的活动，以确定镜头群SDSS的第三次延迟〜J1004+4112
The Longest Delay: a 14.5 Yr Campaign to Determine the Third Time Delay in the Lensing Cluster SDSS~J1004+4112
论文作者
论文摘要
我们为五个图像群集镜头的准重力透镜系统SDSS SDSS 〜J1004+4112的四个明亮图像提供了新的光曲线。光曲线范围为14.5年，并允许测量尾随明亮的数数映像D和领先的图像C之间的时间延迟。对于其他两个独立的时间延迟，我们将获得$ΔT_{bc} = 782.20 \ pm 0.43 $ days（2.14 yr）和$Δt_{ac} = 825.23 \ pm 0.46 $ days（2.26 yr），符合先前的结果。需要信息标准来加重具有不同多项式阶的光曲线模型的结果，以供内在变异性和差异微透镜的效果。使用Akaike信息标准的结果略有不同，但实际上，绝对延迟错误全部由延迟中的$ \ sim 4 \％$ $ cosmic差异主导，而不是统计或系统的测量不确定性。尽管镜头是簇，但由于在几个幅度的几个幅度的水平上进行了微透镜，因此，类星体图像显示出缓慢的差异性。
We present new light curves for the four bright images of the five image cluster-lensed quasar gravitational lens system SDSS~J1004+4112. The light curves span 14.5 yr and allow measurement of the time delay between the trailing bright quasar image D and the leading image C. When we fit all four light curves simultaneously and combine the models using the Bayes information criterion, we find a time delay of $Δt_{DC}= 2458.47 \pm 1.02$ days (6.73 yr), the longest ever measured for a gravitational lens. For the other two independent time delays we obtain $Δt_{BC}=782.20 \pm 0.43$ days (2.14 yr) and $Δt_{AC}= 825.23 \pm 0.46$ days (2.26 yr), in agreement with previous results. The information criterion is needed to weight the results for light curve models with different polynomial orders for the intrinsic variability and the effects of differential microlensing. The results using the Akaike information criterion are slightly different, but, in practice, the absolute delay errors are all dominated by the $\sim 4\%$ cosmic variance in the delays rather than the statistical or systematic measurement uncertainties. Despite the lens being a cluster, the quasar images show slow differential variability due to microlensing at the level of a few tenths of a magnitude.
