Observational Constraints on the Spectral Index
| dc.creator | Liddle, Andrew R | |
| dc.creator | Lyth, David H | |
| dc.date | 1994-01-11 | |
| dc.date | 1994-05-06 | |
| dc.date.accessioned | 2026-07-07T08:58:13Z | |
| dc.date.available | 2026-07-07T08:58:13Z | |
| dc.description | We address the possibility of bounding the spectral index $n$ of primordial density fluctuations, using both the cosmic microwave background (cmb) anisotropy and data on galaxies and clusters. Each piece of galaxy and cluster data is reduced to a value of $σ(R)$ (the linearly evolved {\em rms} density contrast with top hat smoothing on scale $R$) which allows data on different scales to be readily compared. As a preliminary application, we normalise the spectrum using the ten degree variance of the COBE data, and then compare the prediction with a limited sample of low energy data, for the MDM model with various values of $n$, $Ω_ν$ and $h$. With $h=.5$, the data constrain the spectral index to the range $0.7\lsim n \lsim 1.2$. If gravitational waves contribute to the cmb anisotropy with relative strength $R=6(1-n)$ (as in some models of inflation), the lower limit on $n$ is increased to about $0.85$. The uncertainty in $h$ widens this band by about $0.1$ at either end. | |
| dc.description | 11 pages. Revised version with an extended text and comments on damped Lyman alpha systems. Latex file for the text, plus a ps file for the two figures | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9401014 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9401014 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/147238 | |
| dc.subject | Astrophysics | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | Observational Constraints on the Spectral Index | |
| dc.type | text |