A new algorithm to quantify maximum discs in galaxies
A new algorithm to quantify maximum discs in galaxies
复制标题
量化星系中最大圆盘的新算法
DOI：
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复制
发表时间：
2018
影响因子：
4.8
通讯作者：
J. Schombert
中科院分区：
文献类型：
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作者：
Nathaniel Starkman;F. Lelli;S. McGaugh;J. Schombert
旋转曲线的最大圆盘分解对星系中恒星的质量有一个动力学上限。然而，这一术语的确切定义可能是模糊的，并且在使用中各不相同。我们开发了一种算法来鲁棒地量化最大光盘，我们将其应用到175个星系的数据库中。对于高质量、高表面亮度的星系，在斯皮策3.6 $\mu$m波段，最大圆盘质光比为$\Upgramme_{\mathrm{disc}}^{max} < \ 0.7 \;{\mathrm{M}_\odot}/{\mathrm{L}_\odot}$。这接近或仅略高于恒星人口模型的预期。对于低质量，低表面亮度的星系，最大盘质光比非常高，这对于标准的恒星人口预期是不符合物理的。这证实了低质量，低表面亮度的星系是次最大的。然而，最大圆盘程序仍然可以适用于低表面亮度星系，提供了进一步的证据，在星系中的重子和动力学之间的本地耦合。
Maximum disc decompositions of rotation curves place a dynamical upper limit to the mass attributable to stars in galaxies. The precise definition of this term, however, can be vague and varies in usage. We develop an algorithm to robustly quantify the maximum disc and we apply it to 175 galaxies from the SPARC database. For high-mass, high-surface-brightness galaxies, the maximum disc mass-to-light ratio is $\Upsilon_{\mathrm{disc}}^{max} < \ 0.7 \;{\mathrm{M}_\odot}/{\mathrm{L}_\odot}$ in the Spitzer 3.6 $\mu$m band. This is close to or only slightly above the expectations from stellar population models. For low-mass, low-surface-brightness galaxies, the maximum disc mass-to-light ratios are very high, which is unphysical for standard stellar population expectations. This confirms that low-mass, low-surface-brightness galaxies are sub-maximal. However, the maximum-disc procedure can still be applied to low-surface-brightness galaxies, providing further evidence for a local coupling between baryons and dynamics in galaxies.