Ly alpha clouds associated with Population III objects in cold dark matter models

We present a semi-analytical model to test the hypothesis that Ly alpha QSO absorption lines originate in gaseous halos produced by multiple supernova explosions occurring in Population III objects in a CDM cosmological scenario hoping to assess the validity of CDM models and/or constrain their parameters. The preliminary results indicate that the range of N-HI, redshift distribution and metallicity of clouds are well reproduced by CDM if they are associated with galaxy halos or groups. Firm conclusions on clouds with N-HI less than or equal to 10(14) cm(-2) need a more refined study.