We present axisymmetric maximum disk mass models for a sample of 74 spiral galaxies taken from the southern sky Fabry-Perot Tully-Fisher survey by Schommer et al. The sample contains galaxies spanning a large range of morphologies and having rotation widths from 180 km s -1 to 680 km s -1. For each galaxy we have an I-band image and a two-dimensional Hα velocity field. We decompose the disk and bulge by fitting models directly to the I-band image. This method utilizes both the distinct surface brightness profiles and shapes of the projected disk and bulge in the galaxy images. The luminosity profiles and rotation curves are derived using consistent centers, position angles, and inclinations derived from the photometry and velocity maps. The distribution of mass is modeled as a sum of disk and bulge components with distinct, constant mass-to-light ratios. No dark matter halo is included in the fits. The models reproduce the overall structure of the rotation curves in the majority of galaxies, providing good fits to galaxies that exhibit pronounced structural differences in their surface brightness profiles. Of galaxies for which the rotation curve is measured to R23.5 or beyond 75% are well fitted by a mass-traces-light model for the entire region within R23.5. The models for about 20% of the galaxies do not fit well; the failure of most of these models is traced directly to nonaxisymmetric structures, primarily bars but also strong spiral arms. The median I-band M/L of the disk plus bulge is 2.4 ± 0.9 h75 in solar units, consistent with normal stellar populations. These results require either that the mass of dark matter within the optical disk of spiral galaxies is small or that its distribution is very precisely coupled to the distribution of luminous matter.
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机译：我们为74个旋涡星系的样本提供了轴对称最大圆盘质量模型，该样本取自Schommer等人从南部天空法布里-珀罗·塔利-菲舍尔进行的调查。样本中包含的星系范围广泛，并且旋转宽度从180 km s -1到680 km s -1。对于每个星系，我们都有一个I波段图像和一个二维Hα速度场。我们通过将模型直接拟合到I波段图像来分解磁盘和凸起。此方法利用了不同的表面亮度轮廓以及投影盘的形状和星系图像中的凸起。使用一致的中心，位置角和从光度图和速度图得出的倾斜度，可以得出亮度分布和旋转曲线。质量分布被建模为具有明显，恒定的质光比的圆盘和凸出部分的总和。配合中不包含暗物质光环。这些模型再现了大多数星系中旋转曲线的整体结构，从而很好地拟合了在其表面亮度分布中表现出明显结构差异的星系。旋转曲线测量到R23.5或超过75％的星系通过质量跟踪光模型对R23.5内的整个区域进行了很好的拟合。大约20％的星系的模型不太适合;这些模型大多数的失败直接追溯到非轴对称结构，主要是钢筋，但也有坚固的螺旋臂。圆盘加上凸起的I波段中值M / L以太阳单位为2.4±0.9 h75，与正常的恒星种群一致。这些结果要求螺旋星系的光盘内的暗物质质量较小，或者其分布与发光物质的分布非常精确地耦合。
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