The simultaneous advancement of high resolution integral field unit spectroscopy and robust full-spectral fitting codes now make it possible to examine spatially resolved kinematic, chemical composition, and star-formation history from nearby galaxies. We take new MUSE data from the snapshot optical spectroscopic imaging of mergers and pairs for legacy Exploration (SOSIMPLE) survey to examine NGC 7135. With counter-rotation of gas, disrupted kinematics and asymmetric chemical distribution, NGC 7135 is consistent with an ongoing merger. Though well hidden by the current merger, we are able to distinguish stars originating from an older merger, occurring 6–10 Gyr ago. We further find a gradient in ex-situ material with galactocentric radius, with the accreted fraction rising from 0 per cent in the galaxy centre, to ∼7 per cent within 0.6 effective radii.

中文翻译：

---

SOSIMPLE 星系 NGC 7135 中的新旧重大合并

高分辨率积分场单元光谱学和强大的全光谱拟合代码的同时进步现在可以检查附近星系的空间分辨运动学、化学成分和恒星形成历史。我们从合并和对的快照光学光谱成像中获取新的 MUSE 数据，用于传统探索 (SOSIMPLE) 调查，以检查 NGC 7135。由于气体的反向旋转、运动学破坏和不对称化学分布，NGC 7135 与正在进行的合并一致。尽管当前的合并很好地隐藏了，但我们能够区分起源于较旧合并的恒星，发生在 6-10 Gyr 之前。我们进一步发现具有星系中心半径的异地材料梯度，吸积率从星系中心的 0% 上升到 0 以内的 7%。