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Ahmad Mehrabi

Ahmad Mehrabi

Academic rank: Associate Professor
ORCID:
Education: PhD.
ScopusId: 36705117200
HIndex:
Faculty: Faculty of Science
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Phone:

Research

Title
Using our newest VLT-KMOS HII galaxies and other cosmic tracers to test the Lambda cold dark matter tension
Type
JournalPaper
Keywords
galaxies: starburst – dark energy – distance scale – cosmology: observations.
Year
2022
Journal MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
DOI
Researchers Ahmad Mehrabi ، Spyros Basilakos ، Pavlina Tsiapi ، Malonis Plionis ، Robero Terlevich ، Elena Terlevich ، Recardo Chavez ، Fabio Bersolin ، Eduardo Telles

Abstract

We place novel constraints on the cosmokinetic parameters by using a joint analysis of the newest Very Large Telescope (VLT)- K-band Multi Object Spectrograph (KMOS) HII galaxies (HIIG) with the Type Ia Supernovae (SNIa) Pantheon sample. We combine the latter data sets in order to reconstruct, in a model-independent way, the Hubble diagram to as high redshifts as possible. Using a Gaussian process, we derive the basic cosmokinetic parameters and compare them with those of Lambda cold dark matter (CDM). In the case of SNIa, we find that the extracted values of the cosmokinetic parameters are in agreement with the predictions of CDM model. Combining SNIa with high-redshift tracers of the Hubble relation, namely HIIG data, we obtain consistent results with those based on CDM as far as the present values of the cosmokinetic parameters are concerned, but find significant deviations in the evolution of the cosmokinetic parameters with respect to the expectations of the concordance CDM model.