论文标题
磁盘中气体含量异常高的星系
Galaxies with Abnormally High Gas Content in the Disk
论文作者
论文摘要
使用此类星系的可用样品，考虑考虑到给定质量的恒星种群$ M _*$（VHR-GALAXIES）的星系中的气体含量，具有异常高的氢相对质量$ M_ {HI}/M _*$。结果表明，在光学直径$ d_ {25} $中，VHR星系中的HI质量以及具有“正常” HI含量的星系中的质量受到依赖磁盘特定角动量的值的限制。超过$ d_ {25} $的外部气态磁盘，在我们考虑的大多数星系中都包含HI的主要量，这是重力稳定的，并且通常，它们在巨大的径向距离上保留了稳定性参数$ q_ {gas} $的大约恒定值。它允许提出，VHR星系的外部磁盘最近不是获得，而是年龄很高，并且它们的引力不稳定性是恒星形成过程中恒星形成的主要调节剂。在这种情况下，星系的扩展磁盘还应包括旧星星的低亮度恒星组成部分，其延伸远远超出其光学直径$ d_ {25} $。
The content of gas in galaxies with an anomalously high relative mass of hydrogen $M_{HI}/M_*$ for a given mass of the stellar population $M_*$ (VHR-galaxies) is considered, using the available samples of such galaxies. It is shown that, within the optical diameter $D_{25}$, the mass of HI in VHR galaxies, as well as in galaxies with "normal" HI content, is limited by a value that depends on the specific angular momentum of the disk. Outer gaseous disks beyond $D_{25}$, which contain the main amount of HI in most of the galaxies we consider, are gravitationally stable, and, as a rule, they retain an approximately constant value of the stability parameter $Q_{gas}$ over a large range of radial distances. It allows to propose that the outer disks of VHR galaxies are not recently acquired, but are of great age, and their gravitational instability was the main regulator of star formation during their formation. In this case, the extended disks of galaxies should also include a low-brightness stellar components of old stars extending far beyond their optical diameter $D_{25}$.
