The H I Line Width/Linear Diameter Relationship as an Independent Test of the Hubble Constant
The H I Line Width/Linear Diameter Relationship as an Independent Test of the Hubble Constant
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H I 线宽/线直径关系作为哈勃常数的独立测试
DOI：
10.1086/337917
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
D. Russell
中科院分区：
文献类型：
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作者：
D. Russell
旋涡星系的校正HI线宽与线直径(LW/Ld)之间的关系被用来独立地检验哈勃常数的值。在校正了B带和I带的Tully-Fisher(Tf)关系后，将B带关系用于形态/光度类型为Sc I、Sc I.2、Sc I、3、SAB、Sb、Sb I-II和Sb II的星系，得到LW/Ld关系。我们发现，对于这个样品，LW/LD的散射最小，哈勃常数为90-95公里，S~(-1)MPC~(-1)。哈勃常数的较低值在LW/LD关系中产生分离，这是形态类型的函数。由于哈勃常数90-95明显大于最终的重点项目值72公里S-1 MPC-1，因此对Tf、表面亮度起伏和基面进行了比较。这一比较表明，关键项目Tf到21个星团的距离可能太大。对于一个有11个星系团的样本，关键项目的Tf距离提供了一个未经加权的平均哈勃常数77公里S-1Mpc-1，而对于相同的11个星系团，FP、SBF和我们的Tf距离的组合得到H0=91公里S-1Mpc-1。在我们的数据中，一个更微妙的结果是哈勃常数的形态二分法。数据表明，Sc-I星系遵循90-95的哈勃常数，而Sb星系遵循更接近75公里的哈勃常数S-1 Mpc-1。我们考虑了这一结果的可能解释，但结果表明，这种Sb/Sc i哈勃流差异也存在于室女座星系团中，并与先前的研究一致，这些研究表明，一些星系带有与年龄相关的固有红移分量。
The relationship between corrected H I line widths and linear diameters (LW/LD) for spiral galaxies is used as an independent check on the value of the Hubble constant. After calibrating the Tully-Fisher (TF) relation in both the B and I bands, the B-band relation is used for galaxies of morphological/luminosity types Sc I, Sc I.2, Sc I.3, Sab, Sb, Sb I-II, and Sb II to derive the LW/LD relation. We find that for this sample the scatter in the LW/LD is smallest with a Hubble constant of 90-95 km s-1 Mpc-1. Lower values of the Hubble constant produce a separation in the LW/LD relation that is a function of morphological type. Since a Hubble constant of 90-95 is significantly larger than the final Key Project value of 72 km s-1 Mpc-1, a comparison of TF, surface brightness fluctuation (SBF), and fundamental plane (FP) is made. This comparison indicates that the Key Project TF distances to 21 clusters may be too large. For a sample of 11 clusters, the Key Project TF distances provide an unweighted mean Hubble constant of 77 km s-1 Mpc-1, while a combination of the FP, SBF, and our TF distances for the same 11 clusters gives H0 = 91 km s-1 Mpc-1. A more subtle result in our data is a morphological dichotomy in the Hubble constant. The data suggest that Sc I galaxies follow a Hubble constant of 90-95 while Sb galaxies follow a Hubble constant closer to 75 km s-1 Mpc-1. Possible explanations for this result are considered, but it is shown that this Sb/Sc I Hubble flow discrepancy is also present in the Virgo Cluster and is consistent with previous investigations that indicate that some galaxies carry a component of age-related intrinsic redshift.