Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-11-30
Astronomy and Astrophysics
Astrophysics
7 pages, 7 figures, submitted to ApJ
Scientific paper
10.1086/321652
We use published measurements of the transmission power spectrum of the Lyman alpha forest to constrain several parameters that describe cosmology and thermal properties of the intergalactic medium (IGM). A 6 parameter grid is constructed using Particle-Mesh dark matter simulations together with scaling relations to make predictions for the gas properties. We fit for all parameters simultaneously and identify several degeneracies. We find that the temperature of the IGM can be well determined from the fall-off of the power spectrum at small scales. We find a temperature around 20.000 K, dependent on the slope of the gas equation of state. We see no evidence for evolution in the IGM temperature. We place constraints on the amplitude of the dark matter fluctuations. However, contrary to previous results, the slope of the dark matter power spectrum is poorly constrained. This is due to uncertainty in the effective Jeans smoothing scale, which depends on the temperature as well as the thermal history of the gas.
Hui Lam
Tegmark Max
Zaldarriaga Matias
No associations
LandOfFree
Constraints from the Lyman alpha forest power spectrum 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 Constraints from the Lyman alpha forest power spectrum, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Constraints from the Lyman alpha forest power spectrum will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-249180