散射、迁移、再圆化和松弛以构建具有指数分布的星系盘
Scattering, Migration, Re-circularization and Relaxation to Build Out Galaxy Disks with Exponential Profiles
AI总结：
通过散射、迁移和再圆化过程，研究恒星盘的指数分布形成及维持机制，揭示云-星相互作用对盘结构长期稳定的影响。
摘要：
恒星被星际云或大质量团块散射会增加恒星的速度弥散并促进径向盘的指数分布。本文表明，此类散射在达到恒星偏心率的稳态分布函数后，偏心率的增加和减少发生速率相等。其含义是团块/云散射使偏心恒星轨道重新圆化，保持恒星速度弥散在有限范围内。这种再圆化调节盘加热并维持动力学一致性，有助于盘结构的长期存在。偏心率分布函数和再圆化云-星相互作用的存在与云的质量无关，但达到平衡的时间尺度随质量增加而减小。这些计算是在最简单的盘系统中进行的，以突出散射的影响而不受螺旋波、恒星形成和其他过程的干扰。这些计算还揭示了盘演化的分支现象，即在少数情况下团块空间分布的暂时不对称性会将盘推向一个最终状态，即速度弥散和轨道偏心率增加，对应于早期型盘。总体而言，模型强调了一个重要的物理过程，可以使得所有具有星际介质的星系中形成并维持指数分布的恒星盘。
英文摘要：
Scattering of stars by interstellar clouds or massive clumps increases the stellar velocity dispersion and promotes a radial disk profile that is exponential. Here we show that such scattering reaches a steady-state distribution function of stellar eccentricity, after which eccentricity increases and decreases occur at equal rates. The implication is that clump/cloud scattering recircularizes eccentric stellar orbits, keeping the stellar velocity dispersion in a limited range. This re-circularization regulates disk heating and maintains kinematic coherence, contributing to the longevity of disk structures. The eccentricity distribution function and the presence of recircularizing cloud-star interactions are independent of cloud mass but the timescale to reach equilibrium decreases with increasing mass. The calculations are made in the simplest possible disk system to highlight the effects of scattering without contamination from spiral waves, star formation, and other processes. The calculations also reveal a bifurcation in the disk evolutions whereby in a minority of cases temporary asymmetries in the clump spatial distribution drive the disks to an end state of increased velocity dispersion and orbital eccentricity corresponding to early type disks. Overall the models emphasize an important physical process that can make and maintain an exponential stellar disk in all galaxies with a cloudy interstellar medium.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
