AI 中文总结
本研究利用TNG-50模拟分离RPS效应，发现小质量星系群中RPS可在保留恒星盘的情况下缓慢终止蓝色旋涡星系的恒星形成，形成长寿命红贫旋涡星系，为透镜状星系形成提供中间演化路径。
AI 中文摘要
晚型星系在落入大质量暗晕后会通过 ram pressure stripping（RPS， ram 压力剥离）损失气体。由于这一机制主要清除气体成分，而恒星盘基本不受扰动，它提供了一条无需立即发生形态转变就能终止恒星形成的路径。尽管RPS在星系团中已得到充分证实，但小质量星系群中的星系演化通常被归因于并合，这就留下了一个问题：在这些环境中，仅靠RPS是否能驱动蓝色、正在形成恒星的旋涡星系向恒星形成终止的系统转变。我们使用高分辨率宇宙学模拟TNG-50研究了蓝色旋涡星系落入星系群尺度暗晕后的演化过程。我们排除了经历显著并合的系统，从而分离出RPS的效应。我们发现，小质量星系群（M$_{group}<10^{14.5}$ M$_{\rm \odot}$）中的RPS可以在保留恒星盘结构的同时高效终止恒星形成。这种转变是渐进的，落入后的恒星形成终止时标$\gtrsim6$ Gyr，长于并合驱动演化通常对应的约4 Gyr。最终形成的星系主要是红色的贫气旋涡星系，而非完全转变的S0星系，这表明仅靠气体清除不足以产生完全的形态转变。我们的结果表明，星系群环境中的RPS可以产生长寿命的恒星形成终止旋涡星系，它们可能代表了透镜状星系形成之前的一条中间演化路径。
英文摘要
Late-type galaxies lose gas through ram-pressure stripping (RPS) after falling into a massive halo. Because this mechanism primarily removes the gaseous component while leaving the stellar disk largely undisturbed, it provides a pathway for quenching star formation without immediate morphological transformation. While RPS is well established in galaxy clusters, galaxy evolution in low-mass groups is often attributed to mergers, leaving open the question of whether RPS alone can drive the transition from blue, star-forming spirals to quenched systems in these environments. We use the high-resolution cosmological simulation TNG-50 to investigate the evolution of blue spiral galaxies, after their infall into group-scale halos. We excluded systems undergoing significant mergers, thus isolating the effect of RPS. We find that RPS in low-mass groups (M$_{group}<10^{14.5}$ M$_{\odot}$) can efficiently quench star formation while preserving the stellar disk structure. The transformation is gradual, with quenching timescales $\gtrsim6$ Gyr after infall, longer than the $\sim4$ Gyr typically associated with merger-driven evolution. The resulting galaxies are predominantly red, anemic spirals rather than fully transformed S0 systems, indicating that gas removal alone is insufficient to produce complete morphological transformation. Our results show that RPS in group environments can generate long-lived quenched spirals which might represent an intermediate evolutionary pathway preceding the formation of lenticular galaxies.
Comments14 pages, 10 figures. Accepted for publication in ApJ
