Observational Constraints on the Spectral Index

Details Observational Constraints on the Spectral Index Observational Constraints on the Spectral Index

1994-01-11

arxiv.org/abs/astro-ph/9401014v2

Astronomy and Astrophysics

Astrophysics

11 pages. Revised version with an extended text and comments on damped Lyman alpha systems. Latex file for the text, plus a ps

Scientific paper

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 $\sigma(R)$ (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 $n$, $\Omega_\nu$ 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.

Affiliated with

Also associated with

No associations

Rating

Observational Constraints on the Spectral Index does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Observational Constraints on the Spectral Index, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observational Constraints on the Spectral Index will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-309143