We present an end-to-end methodology to measure the effects of weak lensing on individual galaxy-galaxy systems exploiting their kinematic information. Using this methodology, we have measured a shear signal from the velocity fields of 18 weakly-lensed galaxies. We selected a sample of systems based only on the properties of the sources, requiring them to be bright (apparent $i$-band magnitude $ < 17.4$) and in the nearby Universe ($z < 0.15$). We have observed the velocity fields of the sources with WiFeS, an optical IFU on a 2.3m telescope, and fitted them using a simple circular motion model with an external shear. We have measured an average shear of $\langle \gamma \rangle = 0.020 \pm 0.008$ compared to a predicted $\langle \gamma_{pred} \rangle = 0.005$ obtained using median stellar-to-halo relationships from the literature. While still a statistical approach, our results suggest that this new weak lensing methodology can overcome some of the limitations of traditional stacking-based techniques. We describe in detail all the steps of the methodology and make publicly available all the velocity maps for the weakly-lensed sources used in this study.

中文翻译：

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精密弱透镜的首次剪切测量

我们提出了一种端到端的方法来测量弱透镜对利用其运动学信息的单个星系 - 星系系统的影响。使用这种方法，我们测量了来自 18 个弱透镜星系的速度场的剪切信号。我们仅根据源的属性选择了一个系统样本，要求它们是明亮的（明显的 $i$-band 震级 $<17.4$）并且在附近的宇宙中（$z<0.15$）。我们已经使用 WiFeS（一种在 2.3m 望远镜上的光学 IFU）观察源的速度场，并使用带有外部剪切的简单圆周运动模型对其进行拟合。我们测量了 $\langle \gamma \rangle = 0.020 \pm 0.008$ 的平均剪切，与使用文献中恒星-光晕关系中值获得的预测 $\langle \gamma_{pred} \rangle = 0.005$ 相比。虽然仍然是一种统计方法，但我们的结果表明，这种新的弱透镜方法可以克服传统的基于堆叠的技术的一些局限性。我们详细描述了该方法的所有步骤，并公开了本研究中使用的弱透镜源的所有速度图。