郑奕锐，上海交通大学博士后。2017年本科毕业于中国科学技术大学，2021年博士毕业于英国圣安德鲁斯大学。此后，他在上海交通大学沈俊太教授课题组进行博士后研究。郑奕锐在星系形成和演化领域有着广泛的研究兴趣，尤其关注棒旋星系、后星暴星系以及活动星系核反馈效应。Galactic bars can form via the internal bar instability or external tidal perturbations by other galaxies. We systematically compare the properties of the bars formed through the two mechanisms with a series of controlled N-body simulations that form bars through internal or external mechanisms. We create three disk galaxy models with different dynamical “hotness” and evolve them in isolation and under flyby interactions. We then measure the bar properties, focusing on the pattern speed and exponential growth rate. In the cold- and warm-disk models, where bars can form spontaneously in isolation, tidally induced bars are promoted to a more “advanced” evolutionary stage. However, these bars have similar pattern speeds and growth timescales to those formed spontaneously within the same disk. In the hot-disk model, which avoids the internal bar instability in isolation, a bar forms only under perturbations and rotates/grows more slowly than those in the cold and warm disks. Thus, if “tidally induced bars” refer exclusively to those in galaxies that are otherwise stable against bar instability, they indeed rotate/grow more slowly than internally induced ones. However, these differences are due to the differences in the internal properties of the bar host galaxies, not the different formation mechanisms.I will also show the preliminary results on the effects of classical bulges on the bar formation and properties, as well as the long-term plan of this project.