Quintessence reconstructed: New constraints and tracker viability
Abstract
We update and extend our previous work reconstructing the potential of a quintessence field from current observational data. We extend the cosmological data set to include new supernova data, plus information from the cosmic microwave background and from baryon acoustic oscillations. We extend the modeling by considering Pade approximant expansions as well as Taylor series, and by using observations to assess the viability of the tracker hypothesis. We find that parameter constraints have improved by a factor of 2, with a strengthening of the preference of the cosmological constant over evolving quintessence models. Present data show some signs, though inconclusive, of favoring tracker models over nontracker models under our assumptions.
 Authors:
 Astronomy Centre, University of Sussex, Brighton BN1 9QH (United Kingdom)
 Publication Date:
 OSTI Identifier:
 20935205
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevD.75.023502; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BARYONS; COSMIC RADIATION; COSMOLOGICAL CONSTANT; COSMOLOGICAL MODELS; COSMOLOGY; NONLUMINOUS MATTER; OSCILLATIONS; PADE APPROXIMATION; RADIOWAVE RADIATION; RELICT RADIATION; SERIES EXPANSION; SUPERNOVAE
Citation Formats
Sahlen, Martin, Liddle, Andrew R., and Parkinson, David. Quintessence reconstructed: New constraints and tracker viability. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.023502.
Sahlen, Martin, Liddle, Andrew R., & Parkinson, David. Quintessence reconstructed: New constraints and tracker viability. United States. doi:10.1103/PHYSREVD.75.023502.
Sahlen, Martin, Liddle, Andrew R., and Parkinson, David. Mon .
"Quintessence reconstructed: New constraints and tracker viability". United States.
doi:10.1103/PHYSREVD.75.023502.
@article{osti_20935205,
title = {Quintessence reconstructed: New constraints and tracker viability},
author = {Sahlen, Martin and Liddle, Andrew R. and Parkinson, David},
abstractNote = {We update and extend our previous work reconstructing the potential of a quintessence field from current observational data. We extend the cosmological data set to include new supernova data, plus information from the cosmic microwave background and from baryon acoustic oscillations. We extend the modeling by considering Pade approximant expansions as well as Taylor series, and by using observations to assess the viability of the tracker hypothesis. We find that parameter constraints have improved by a factor of 2, with a strengthening of the preference of the cosmological constant over evolving quintessence models. Present data show some signs, though inconclusive, of favoring tracker models over nontracker models under our assumptions.},
doi = {10.1103/PHYSREVD.75.023502},
journal = {Physical Review. D, Particles Fields},
number = 2,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}

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