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Cosmological Constraints from Hubble parameter $H(z)$ and SN Ia observations

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 نشر من قبل Tong-Jie Zhang Dr.
 تاريخ النشر 2008
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Hui Lin




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In this paper, we use a set of observational $H(z)$ data (OHD) to constrain the $Lambda$CDM cosmology. This data set can be derived from the differential ages of the passively evolving galaxies. Meanwhile, the $mathcal {A}$-parameter, which describes the Baryonic Acoustic Oscillation (BAO) peak, and the newly measured value of the Cosmic Microwave Background (CMB) shift parameter $mathcal {R}$ are used to present combinational constraints on the same cosmology. The combinational constraints favor an accelerating flat universe while the flat $Lambda$CDM cosmology is also analyzed in the same way. We obtain a result compatible with that by many other independent cosmological observations. We find that the observational $H(z)$ data set is a complementarity to other cosmological probes.



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