Searches for gravitational microlensing events are traditionally concentrated on the central regions of the Galactic bulge but many microlensing events are expected to occur in the Galactic plane, far from the Galactic Center. Owing to the difficulty in conducting high-cadence observations of the Galactic plane over its vast area, which are necessary for the detection of microlensing events, their global properties were hitherto unknown. Here, we present results of the first comprehensive search for microlensing events in the Galactic plane. We searched an area of almost 3000 square degrees along the Galactic plane ( ##IMG## [http://ej.iop.org/images/0067-0049/249/1/16/apjsab9366ieqn1.gif] {$| b| \lt 7^\circ $} ,0° < l < 50°,190° < l < 360°) observed by the Optical Gravitational Lensing Experiment (OGLE) during 2013–2019 and detected 630 events. We demonstrate that the mean Einstein timescales of Galactic plane microlensing events ...

中文翻译：

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OGLE-IV银河平面场中的微透镜光学深度和事件发生率

传统上，对引力微透镜事件的搜索通常集中在银河凸起的中心区域，但预计在距银河中心较远的银河平面上会发生许多微透镜事件。由于很难在银河系的大面积区域上进行高节奏的观测，这对于检测微透镜事件是必不可少的，因此它们的整体性质是迄今未知的。在这里，我们介绍了首次全面搜索银河平面微透镜事件的结果。我们沿着银河平面搜索了近3000平方度的区域（## IMG ## [http://ej.iop.org/images/0067-0049/249/1/16/apjsab9366ieqn1.gif] {$ | b | \ lt 7 ^ \ circ $}，0°<l <50°，190°<l < 在2013-2019年期间通过光学引力透镜实验（OGLE）观测到360°），并检测到630个事件。我们证明银河平面微透镜事件的平均爱因斯坦时标...