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Khaled Saaidi

Khaled Saaidi

Academic rank: Professor
ORCID:
Education: PhD.
ScopusId: 4567832
Faculty: Faculty of Science
Address: Department of Physics, Faculty of Science, University of Kurdistan, Pasdaran Street, Sanandaj, Kurdistan, Iran. 2th Address: Science and Technology Park of Kurdistan, Buo Ali Boolvar, Ghane Square, Baharan Town , Sanandaj, Kurdistan, Iran.
Phone: 08733776900

Research

Title
Interacting scalar tensor cosmology in light of SNeIa, CMB, BAO and OHD observational data sets
Type
JournalPaper
Keywords
chameleon-like scalar field, CMB, SNeIa, OHD observational
Year
2016
Journal EUROPEAN PHYSICAL JOURNAL C
DOI
Researchers Saeid worya rabiei ، Haidar Shaikhahmadi ، Khaled Saaidi ، Ali Aghamohammadi

Abstract

‎During this work‎, ‎an interacting chameleon like scalar field scenario‎, ‎by considering SNeIa‎, ‎CMB‎, ‎BAO and OHD data sets is investigated‎. ‎In fact‎, ‎the investigation is realized by introducing an ansatz for the effective dark energy equation of state‎, ‎which mimics the behaviour of chameleon like models‎. ‎Based on this assumption‎, ‎some cosmological parameters including Hubble‎, ‎deceleration and coincidence parameters in such mechanism are analysed‎. ‎It is realized that‎, ‎to estimate the free parameters of a theoretical model‎, ‎by regarding the systematic errors it better the whole of the above observational data sets to be considered‎. ‎In fact‎, ‎if one considers SNeIa‎, ‎CMB and BAO but disregards OHD it maybe leads to different results‎. ‎Also to get a better overlap between the counters with the constraint $\chi _{\rm{m}}^2\leq 1$‎, ‎the $\chi _{\rm{T}}^2$ function could be re-weighted‎. ‎The relative probability functions are plotted for marginalized likelihood $\mathcal{L} (\Omega_{\rm{m0}}‎ ‎,\omega_1,‎ ‎\beta)$ according to two dimensional confidence levels $68.3\%$‎, ‎$90\%$ and $95.4\%$‎. ‎Meanwhile‎, ‎the value of free parameters which maximize the marginalized likelihoods using above confidence levels are obtained‎. ‎In addition‎, ‎based on these calculations the minimum value of $\chi^2$ based on free parameters of an ansatz for the effective dark energy equation of state are achieved‎.