最新观测资料对广义快子场模型的限制
Constraints on the generalized tachyon field models from latest observational data
摘要：
我们考虑的约束广义快子场（GTF）模型从最新的观测数据（包括182金SNIa数据，移位参数，和声学标度）。在68.3%的置信水平下，我们得到了仅作为暗能量成分的GTF的$Ω_{\rm m}=0.37\pm0.01$、$k_0=0.09^{+0.04}_{-0.03}$、$α=1.8^{+7.4}_{-0.7}$（参数的最佳拟合值）和$z_{q=0}\sim 0.47-0.51$（过渡红移）;作为暗能量和暗物质的统一的GTF的$k_0=0.21^{+0.20}_{-0.18}$、$α=0.57\pm0.01$和$z_{q=0}\sim 0.49-0.68$。在这两种情况下，GTF都像早期宇宙中的暗物质一样演化。通过模型比较统计和对独立的$H(z)$数据的检验，我们发现GTF暗能量场景比$Λ$ CDM模型更受青睐，而组合数据显示$Λ$ CDM模型比GTF统一暗物质更受青睐。对于GTF暗能量分量，物质密度的涨落与线性密度扰动的增长是一致的。对于GTF统一暗物质，GTF密度波动的增长对于$a\to1$增长得更慢，这意味着GTF不表现为经典的$Λ$ CDM场景。
英文摘要：
We consider constraints on generalized tachyon field (GTF) models from latest observational data (including 182 gold SNIa data, the shift parameter, and the acoustic scale). We obtain at 68.3% confidence level $Ω_{\rm m}=0.37\pm0.01$, $k_0=0.09^{+0.04}_{-0.03}$, $α=1.8^{+7.4}_{-0.7}$ (the best-fit values of the parameters) and $z_{q=0}\sim 0.47-0.51$ (the transitional redshift) for GTF as dark energy component only; $k_0=0.21^{+0.20}_{-0.18}$, $α=0.57\pm0.01$ and $z_{q=0}\sim 0.49-0.68$ for GTF as unification of dark energy and dark matter. In both cases, GTF evolves like dark matter in the early universe. By applying model-comparison statistics and test with independent $H(z)$ data, we find GTF dark energy scenario is favored over the $Λ$CDM model, and the $Λ$CDM model is favored over GTF unified dark matter by the combined data. For GTF as dark energy component, the fluctuations of matter density is consistent with the growth of linear density perturbations. For GTF unified dark matter, the growth of GTF density fluctuations grow more slowly for $a\to1$, meaning GTF do not behave as classical $Λ$CDM scenarios.
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。
