Recent data on the high-redshift abundance of damped Lyalpha systems are compared with theoretical predictions for `blue' (i.e. <e1>n<~</e1>1) mixed dark matter (MDM) models. The results show that decreasing the hot component fraction Omega_nu and/or increasing the primordial spectral index n leads to an earlier epoch of cosmic structure formation. We also show, however, that varying Omega_nu and n in these ways makes the models barely consistent with the observed abundance of galaxy clusters. Therefore, requiring both the observational constraints on damped Lyalpha systems and the cluster abundance to be satisfied simultaneously represents a challenge for the MDM class of models.

The Epoch of Structure Formation in Blue Mixed Dark Matter Models

LUCCHIN, FRANCESCO;MATARRESE, SABINO;MOSCARDINI, LAURO
1996

Abstract

Recent data on the high-redshift abundance of damped Lyalpha systems are compared with theoretical predictions for `blue' (i.e. n<~1) mixed dark matter (MDM) models. The results show that decreasing the hot component fraction Omega_nu and/or increasing the primordial spectral index n leads to an earlier epoch of cosmic structure formation. We also show, however, that varying Omega_nu and n in these ways makes the models barely consistent with the observed abundance of galaxy clusters. Therefore, requiring both the observational constraints on damped Lyalpha systems and the cluster abundance to be satisfied simultaneously represents a challenge for the MDM class of models.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11577/135929
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 6
  • ???jsp.display-item.citation.isi??? 7
social impact