Is there a fundamental acceleration scale in galaxies
Is there a fundamental acceleration scale in galaxies
复制标题
星系中是否存在基本的加速尺度
DOI：
10.1093/mnras/stz961
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发表时间：
2019
影响因子：
4.8
通讯作者：
Zhou Y.
中科院分区：
文献类型：
--
作者：
Chang Z.;Zhou Y.
米尔格罗姆修正的牛顿动力学(MOND)可以很好地解释星系中的质量差异问题，而不需要引用暗物质。MOND理论预言了星系中普遍存在的恒加速度标度，低于这个标度，牛顿动力学就不再有效了。最近，罗德里格斯等人。用贝叶斯推断分析了193个高质量的盘状星系，他们得出结论：基本加速尺度存在的概率基本上为0。在这篇论文中，我们用同样的方法重新探讨了同样的问题：星系中是否存在基本的加速度标度？我们用星系参数和可变的加速标度对175个SPARC星系的每个星系的自转曲线进行了高斯先验拟合。在对干扰参数进行边际化后，我们发现加速度尺度的边际后验分布变得更宽。加速度表的全局最优拟合度与边际后验分布之间的不相容程度大大降低。然而，仍然有证据表明，拒绝将MOND作为一种基本理论。需要更准确的观测来排除或证实星系中存在基本的加速度标度。
Milgrom’s modified Newtonian dynamics (MOND) can explain well the mass discrepancy problem in galaxy without invoking dark matter. The MOND theory predicts a universal constant acceleration scale in galaxy, below which the Newtonian dynamics is no longer valid. Recently, Rodrigues et al. analysed 193 high-quality disc galaxies by using Bayesian inference and they concluded that the probability of existence of a fundamental acceleration scale is essentially 0. In this paper, we use the same method to revisit the same question: Is there a fundamental acceleration scale in galaxies? We fit each galaxy rotation curve of 175 SPARC galaxies with Gaussian priors on galaxy parameters and a variable acceleration scale. After marginalizing over the nuisance parameters, we find that the marginalized posterior distributions of the acceleration scale become broad. The incompatibility between the global best fit and the marginalized posterior distributions of the acceleration scale is greatly reduced. However, there still exists evidence that rejects MOND as a fundamental theory. More accurate observations are needed to exclude or confirm the existence of a fundamental acceleration scale in galaxies.