Testing Models of the Ly α Forest
Abstract
The structure of the Lyα forest is simulated for a variety of Cold Dark Matter (CDM) dominated cosmological scenarios: CHDM, OCDM, ACDM, SCDM, and tCDM. Synthetic spectra are constructed duplicating the resolution, wavelength and signal-to-noise ratio of a Keck HIRES spectrum of Q1937-1009. The predicted cumulative flux distribution of the ACDM model agrees with the measured to within 5%. This represents the most accurate agreement achieved to date between the predictions of CDM in the non-linear regime and the observed universe. Significantly larger median Doppler parameters are found in the measured spectra than predicted, indicating a possible need to introduce additional energy injection throughout the intergalactic medium, as may be provided by late He II reionization.
- Publication:
-
Lighthouses of the Universe: The Most Luminous Celestial Objects and Their Use for Cosmology
- Pub Date:
- 2002
- DOI:
- 10.1007/10856495_77
- Bibcode:
- 2002luml.conf..503M