Preprint astro-ph Bumpy Power Spectra and ∆T/T

• Main Authors: Louise M. Griffiths, Joseph Silk, Saleem Zaroubi
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2008
• Subjects: Antarctic; Hubble; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.317.1260; http://arxiv.org/pdf/astro-ph/0010571v2.pdf

With the recent publication of the measurements of the radiation angular power spectrum from the BOOMERanG Antarctic flight (de Bernardis et al. 2000), it has become apparent that the currently favoured spatially-flat cold dark matter model (matter density parameter Ωm = 0.3, flatness being restored by a cosmological constant ΩΛ = 0.7, Hubble parameter h = 0.65, baryon density parameter Ωbh 2 = 0.02) no longer provides a good fit to the data. We describe a phenomenological approach to resurrecting this paradigm. We consider a primordial power spectrum which incorporates a bump, arbitrarily placed at kb, and characterized by a Gaussian in log k of standard deviation σb and amplitude Ab, that is superimposed onto a scale-invariant power spectrum. We generate a range of theoretical models that include a bump at scales consistent with cosmic microwave background and large-scale structure observations, and perform a simple χ 2 test to compare our models with the COBE DMR data and the recently published BOOMERanG and MAXIMA data. Unlike models that include a high baryon content, our models predict a low third acoustic peak. We