Effect of the length of inflation on angular TT and TE power spectra in power-law inflation
نویسندگان
چکیده
The effect of the length of inflation on the power spectra of scalar and tensor perturbations is estimated using the power-law inflation model with a scale factor of a(η) = (η) = t. Considering various pre-inflation models with radiation-dominated or scalar matter-dominated periods before inflation in combination with two matching conditions, the temperature angular power spectrum (TT) and temperature-polarization cross-power spectrum (TE) are calculated and a likelihood analysis is performed. It is shown that the discrepancies between the Wilkinson Microwave Anisotropy Probe (WMAP) data and the ΛCDM model, such as suppression of the spectrum at l = 2,3 and oscillatory behavior, may be explained by the finite length of inflation model if the length of inflation is near 60 e-folds and q ≥ 300. The proposed models retain similar values of χ to that achieved by the ΛCDM model with respect to fit to the WMAP data, but display different characteristics of the angular TE power spectra at l ≤ 20. PACS number: 98.80.Cq
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