Dark energy equation of state parameter and its evolution at low redshift
Abstract
In this paper, we constrain dark energy models using a compendium of observations at low redshifts. We consider the dark energy as a barotropic fluid, with the equation of state a constant as well the case where dark energy equation of state is a function of time. The observations considered here are Supernova Type Ia data, Baryon Acoustic Oscillation data and Hubble parameter measurements. We compare constraints obtained from these data and also do a combined analysis. The combined observational constraints put strong limits on variation of dark energy density with redshift. For varying dark energy models, the range of parameters preferred by the supernova type Ia data is in tension with the other low redshift distance measurements.
 Authors:
 Indian Institute of Science Education and Research Mohali, SAS Nagar, Mohali 140306, Punjab (India)
 Publication Date:
 OSTI Identifier:
 22676173
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 06; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BARYONS; COMPARATIVE EVALUATIONS; DISTANCE; ENERGY DENSITY; ENERGY MODELS; EQUATIONS OF STATE; EVOLUTION; FLUIDS; NONLUMINOUS MATTER; OSCILLATIONS; RED SHIFT; SIMULATION; TIME DEPENDENCE; TYPE I SUPERNOVAE; VARIATIONS
Citation Formats
Tripathi, Ashutosh, Sangwan, Archana, and Jassal, H.K., Email: ashutosh_tripathi@fudan.edu.cn, Email: archanakumari@iisermohali.ac.in, Email: hkjassal@iisermohali.ac.in. Dark energy equation of state parameter and its evolution at low redshift. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/06/012.
Tripathi, Ashutosh, Sangwan, Archana, & Jassal, H.K., Email: ashutosh_tripathi@fudan.edu.cn, Email: archanakumari@iisermohali.ac.in, Email: hkjassal@iisermohali.ac.in. Dark energy equation of state parameter and its evolution at low redshift. United States. doi:10.1088/14757516/2017/06/012.
Tripathi, Ashutosh, Sangwan, Archana, and Jassal, H.K., Email: ashutosh_tripathi@fudan.edu.cn, Email: archanakumari@iisermohali.ac.in, Email: hkjassal@iisermohali.ac.in. Thu .
"Dark energy equation of state parameter and its evolution at low redshift". United States.
doi:10.1088/14757516/2017/06/012.
@article{osti_22676173,
title = {Dark energy equation of state parameter and its evolution at low redshift},
author = {Tripathi, Ashutosh and Sangwan, Archana and Jassal, H.K., Email: ashutosh_tripathi@fudan.edu.cn, Email: archanakumari@iisermohali.ac.in, Email: hkjassal@iisermohali.ac.in},
abstractNote = {In this paper, we constrain dark energy models using a compendium of observations at low redshifts. We consider the dark energy as a barotropic fluid, with the equation of state a constant as well the case where dark energy equation of state is a function of time. The observations considered here are Supernova Type Ia data, Baryon Acoustic Oscillation data and Hubble parameter measurements. We compare constraints obtained from these data and also do a combined analysis. The combined observational constraints put strong limits on variation of dark energy density with redshift. For varying dark energy models, the range of parameters preferred by the supernova type Ia data is in tension with the other low redshift distance measurements.},
doi = {10.1088/14757516/2017/06/012},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2017,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}

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