# Observational Estimates of the Initial Power Spectrum at Small Scale from Lyα Absorbers

@article{Demianski2003ObservationalEO,
title={Observational Estimates of the Initial Power Spectrum at Small Scale from Ly$\alpha$ Absorbers},
author={M. Demia'nski and Andrei G. Doroshkevich},
journal={The Astrophysical Journal},
year={2003},
volume={597},
pages={81-97}
}
• Published 27 April 2003
• Physics
• The Astrophysical Journal
We present a new method of measuring the power spectrum of initial perturbations to an unprecedentedly small scale of ~10 h-1 kpc. We apply this method to a sample of 4500 Lyα absorbers and recover the cold dark matter (CDM)-like power spectrum at scales ≥300 h-1 kpc with a precision of ~10%. However, at scales ~10-300 h-1 kpc, the measured and CDM-like spectra are noticeably different. This result suggests a complex inflation with generation of excess power at small scales. The magnitude and…
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