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Effect of the length of inflation on angular TT and TE power spectra in power-law inflation

Shiro Hirai·Tomoyuki Takami
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Abstract

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(t) = t^q. 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 LCDM 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 chi^2 to that achieved by the LCDM model with respect to fit to the WMAP data, but display different characteristics of the angular TE power spectra at l < 20.

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Shiro Hirai, Tomoyuki Takami. 2005-12-13. Effect of the length of inflation on angular TT and TE power spectra in power-law inflation. https://doi.org/10.1088/0264-9381%2F23%2F7%2F019

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