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arXiv 0909.5203astro-ph.COastro-ph.GAgr-qchep-ph
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暗晕尺度长度内星系面密度的普适性

Universality of galactic surface densities within one dark halo scale-length

Gianfranco Gentile, Benoit Famaey, HongSheng Zhao, Paolo Salucci

摘要:

最近发现,在一个暗晕尺度长度内的平均暗物质表面密度--在这个半径内,暗物质的体积密度分布保持近似平坦--在很大范围的星系中是恒定的。这种比例关系适用于亮度范围为14等的星系和整个哈勃序列。在这里,我们报告的发光物质的表面密度也是恒定的暗晕的一个尺度长度内。这意味着星系中发光部分产生的引力加速度在这个半径上总是相同的。虽然总的发光物质与暗物质的比例不是恒定的,但在一个晕尺度内,它是恒定的。我们的发现可以解释为星系中发光物质和暗物质的封闭表面密度之间的密切相关性。

英文摘要:

It was recently discovered that the mean dark matter surface density within one dark halo scale length - the radius within which the volume density profile of dark matter remains approximately flat - is constant across a wide range of galaxies. This scaling relation holds for galaxies spanning a luminosity range of 14 magnitudes and the whole Hubble sequence. Here we report that the luminous matter surface density is also constant within one scale length of the dark halo. This means that the gravitational acceleration generated by the luminous component in galaxies is always the same at this radius. Although the total luminous-to-dark matter ratio is not constant, within one halo scale length it is constant. Our finding can be interpreted as a close correlation between the enclosed surface densities of luminous and dark matter in galaxies.

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。

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