AI 中文总结
本研究利用175个星系的SPARC样本检验无暗物质的CCC框架，改进其密度过渡形式后，发现单参数CCC拟合旋转曲线的效果与MOND相当，且优于NFW模型，其特征加速度与MOND的a₀量级和散度均接近。
AI 中文摘要
为解释詹姆斯·韦伯空间望远镜（JWST）高红移观测结果而提出的协变耦合常数（Covarying Coupling Constants, CCC）框架，包含一种与局域密度挂钩的协变常数有效质量场机制，可在无需粒子暗物质的情况下修正星系动力学。我们将该模型与包含175个盘星系的完整斯皮策测光与精确旋转曲线（Spitzer Photometry and Accurate Rotation Curves, SPARC）样本进行检验，拓展了此前仅针对少数天体的研究。我们采用逆公式构建模型——即每个模型都从观测到的旋转曲线预测重子旋转曲线，使用约化χ²_ν指标，在完全相同的基准下将CCC与修正牛顿动力学（Modified Newtonian Dynamics, MOND）以及单参数、双参数纳瓦罗-弗伦克-怀特（Navarro-Frenk-White, NFW）暗晕模型进行对比。我们证实此前研究中公布的陡峭密度截断是非物理的，并用平滑过渡取而代之——这是MOND插值函数在密度空间的对应形式，且未引入新参数。单参数平滑CCC模型的表现与逐星系拟合的MOND相当：56%的星系中CCC的χ²_ν更低，平均χ²_ν分别为2.58和2.65，配对差异不具有统计显著性；而双参数NFW模型的拟合质量分布宽得多，拟合效果差或受边界限制的样本尾部更显著，平均χ²_ν约为7。CCC的截断密度并非普适，散度为0.82 dex，且与星系尺度相关，这与将扁平盘系统近似为球对称重构的定性结果一致。然而，将其转换为加速度形式a_t = V_flat²/R_t后，在91个有分辨的星系子样本中散度为0.33 dex，与MOND的特征加速度a₀的散度（0.34 dex）相当，量级也同为约2×10⁻¹⁰ m/s²，且其与尺度的相关性消失。尽管CCC并非为星系动力学设计，但它对旋转曲线的描述效果与逐星系拟合的MOND相当。
英文摘要
The Covarying Coupling Constants (CCC) framework, developed to account for high-redshift JWST observations, contains a mechanism -- a covarying-constant effective mass field keyed to local density -- that modifies galactic dynamics without particle dark matter. We test it against the full Spitzer Photometry and Accurate Rotation Curves (SPARC) sample of 175 disc galaxies, extending an earlier study of a few objects. Working in an inverse formulation, in which each model predicts the baryonic rotation curve from the observed one, we compare CCC against Modified Newtonian Dynamics (MOND) and one- and two-parameter Navarro-Frenk-White (NFW) haloes on identical footing, using the reduced $χ^2_ν$. We show that the published sharp density turn-off in the earlier study is unphysical and replace it with a smooth transition -- the density-space analogue of the MOND interpolating function, introducing no new parameter. One-parameter smooth-CCC then performs comparably to galaxy-by-galaxy fitted MOND (the lower $χ^2_ν$ in 56 per cent of galaxies, mean $χ^2_ν$ of 2.58 versus 2.65; the paired difference is not significant), while two-parameter NFW shows a substantially broader fit-quality distribution and a larger tail of poor or boundary-limited fits (mean $χ^2_ν\approx 7$). The CCC turn-off density is not universal (scatter 0.82 dex) and correlates with galaxy size, qualitatively consistent with a spherical reconstruction applied to flattened disc systems. Recast as an acceleration, however, $a_t = V_{\rm flat}^2/R_t$ has scatter 0.33 dex (on the 91-galaxy resolved subset) -- matching the MOND scale $a_0$ (0.34 dex) -- and comparable magnitude of order $2 \times 10^{-10}$ m/s$^2$, with its size correlation removed. Though not designed for galactic dynamics, CCC describes rotation curves as well as galaxy-by-galaxy fitted MOND.
Comments16 pages, 8 figures, 7 tables, a montage of 165 galaxy rotation curves as supplementary material. Comments are welcomed
