标题： 中间膨胀和幂律膨胀在声速恒定的快子模型中 显示英文标题

标题： Intermediate and Power-Law Inflation in the Tachyon Model with Constant Sound Speed

摘要： 通过采用中间和幂律尺度因子，我们研究了具有常数声速的快子膨胀。 我们在该模型中对扰动和非高斯性参数进行了一些数值分析，并将结果与观测数据进行了比较。 通过使用来自Planck2018 TT, TE, EE+lowE+lensing+BAO+BK14数据的标量谱指数和张量-标量比的约束，来自Planck2018 TT, TE, EE+lowEB+lensing数据的标量谱指数运行的约束，以及来自Planck2018 TT, TE, EE+lowE+lensing+BK14+BAO+LIGO和Virgo2016数据的张量谱指数的约束，我们找到了该模型参数在$68\%$ CL和$95\%$ CL下的观测可行范围。 我们还分析了该模型在等边和正交构型中的非高斯特征。 基于Planck2018 TTT、EEE、TTE和EET数据，我们发现声速的约束为$0.276\leq c_{s}\leq 1$在$68\%$CL，$0.213\leq c_{s}\leq 1$在$95\%$CL，以及$0.186\leq c_{s}\leq 1$在$97\%$CL。 显示英文摘要

摘要： By adopting the intermediate and power-law scale factors, we study the tachyon inflation with constant sound speed. We perform some numerical analysis on the perturbation and non-gaussianity parameters in this model and compare the results with observational data. By using the constraints on the scalar spectral index and tensor-to-scalar-ratio, obtained from Planck2018 TT, TE, EE+lowE+lensing+BAO+BK14 data, the constraint on the running of the scalar spectral index obtained from Planck2018 TT, TE, EE+lowEB+lensing data, and constraint on tensor spectral index obtained from Planck2018 TT, TE, EE +lowE+lensing+BK14+BAO+LIGO and Virgo2016 data, we find the observationally viable ranges of the model's parameters at both $68\%$ CL and $95\%$ CL. We also analyze the non-gaussian features of the model in the equilateral and orthogonal configurations. Based on Planck2018 TTT, EEE, TTE and EET data, we find the constraints on the sound speed as $0.276\leq c_{s}\leq 1$ at $68\%$ CL, $0.213\leq c_{s}\leq 1$ at $95\%$ CL, and $0.186\leq c_{s}\leq 1$ at $97\%$ CL.