The Radial Acceleration Relation (RAR): Crucial Cases of Dwarf Disks and Low-surface-brightness Galaxies
The Radial Acceleration Relation (RAR): Crucial Cases of Dwarf Disks and Low-surface-brightness Galaxies
复制标题
径向加速度关系（RAR）：矮盘和低表面亮度星系的关键案例
DOI：
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发表时间：
2018
影响因子：
4.9
通讯作者：
J. Fontaine
中科院分区：
文献类型：
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作者：
C. D. Paolo;P. Salucci;J. Fontaine
McGaugh等人发现，在一个大的圆盘系统样本中，总径向加速度g和它们的分量gb之间存在紧密的非线性关系，这些关系是由重子物质的分布引起的。本文在Karukes & Salucci和Di Paolo & Salucci的基础上，研究了矮盘螺旋和低表面亮度（LSB）星系中这种关系的存在性。我们有36个矮盘螺旋星系和72个LSB星系的精确质量分布图。这些星系的加速度覆盖了McGaugh范围，但也比McGaugh等人的最小加速度低一个数量级，并且跨越了不同的哈勃类型。我们发现，在我们的样本中，g与gb的关系有一个非常不同的轮廓和其他固有的新特性，其中，依赖于第二个变量：星系半径，归一化为光学半径Ropt，在这里测量两个加速度。我们证明了新的远非平凡的g对关系是圆盘系统中重子和暗物质（DM）的复杂协调质量分布的直接结果。我们的分析表明，McGaugh等人的关系是一种新的普遍关系的极限情况，这种关系可以很好地用标准的“牛顿引力中的DM光环”范式来框定。
McGaugh et al. have found, in a large sample of disk systems, a tight nonlinear relationship between the total radial accelerations g and their components gb that have arisen from the distribution of the baryonic matter. Here, we investigate the existence of such a relation in Dwarf Disk Spirals and Low Surface Brightness (LSB) galaxies on the basis of Karukes & Salucci and Di Paolo & Salucci. We have accurate mass profiles for 36 Dwarf Disk Spirals and 72 LSB galaxies. These galaxies have accelerations that cover the McGaugh range but also reach out to one order of magnitude below the smallest accelerations present in McGaugh et al. and span different Hubble Types. We found, in our samples, that the g versus gb relation has a very different profile and also other intrinsic novel properties, among those, the dependence on a second variable: the galactic radius, normalized to the optical radius Ropt, at which the two accelerations are measured. We show that the new far from trivial g versus relationship is a direct consequence of the complex coordinated mass distributions of the baryons and the dark matter (DM) in disk systems. Our analysis shows that the McGaugh et al. relation is a limiting case of a new universal relation that can be very well framed in the standard “DM halo in the Newtonian Gravity” paradigm.