### Resumen

We propose to use alternative cosmic tracers to measure the dark energy equation of state and the matter content of the Universe [w(z) & Ω_{m}]. Our proposed method consists of two components: (a) tracing the Hubble relation using HII galaxies which can be detected up to very large redshifts, z ∼ 4, as an alternative to supernovae type Ia, and (b) measuring the clustering pattern of X-ray selected AGN at a median redshift of ∼ 1. Each component of the method can in itself provide interesting constraints on the cosmological parameters, especially under our anticipation that we will reduce the corresponding random and systematic errors significantly. However, by joining their likelihood functions we will be able to put stringent cosmological constraints and break the known degeneracies between the dark energy equation of state (whether it is constant or variable) and the matter content of the universe and provide a powerful and alternative route to measure the contribution to the global dynamics and the equation of state of dark energy. A preliminary joint analysis of X-ray selected AGN clustering (based on the largest to-date XMM survey; the 2XMM) and the currently largest SNIa sample, the Constitution set (Hicken et al.), using as priors a flat universe and the WMAP5 normalization of the power-spectrum, provides: Ω_{m} 0.27 0.02 and w= -0.96 0.07. Equivalent and consistent results are provided by the joint analysis of X-ray selected AGN clustering and the latest Baryonic Acoustic Oscillation measures, providing: Ω_{m} 0.270.02 and w= -0.970.04.

Idioma original | Inglés |
---|---|

Número de artículo | 012025 |

Publicación | Journal of Physics: Conference Series |

Volumen | 222 |

N.º | 1 |

DOI | |

Estado | Publicada - 1 ene 2010 |

Evento | 1st Mediterranean Conference on Classical and Quantum Gravity, MCCQG 2009 - Kolymbari, Crete, Grecia Duración: 14 sep 2009 → 18 sep 2009 |

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*Journal of Physics: Conference Series*,

*222*(1), [012025]. https://doi.org/10.1088/1742-6596/222/1/012025

}

*Journal of Physics: Conference Series*, vol. 222, n.º 1, 012025. https://doi.org/10.1088/1742-6596/222/1/012025

**The dark energy equation of state using alternative cosmic high-z tracers.** / Plionis, M.; Terlevich, R.; Basilakos, S.; Bresolin, F.; Terlevich, E.; Melnick, J.; Chavez, R.

Resultado de la investigación: Contribución a una revista › Artículo de la conferencia

TY - JOUR

T1 - The dark energy equation of state using alternative cosmic high-z tracers

AU - Plionis, M.

AU - Terlevich, R.

AU - Basilakos, S.

AU - Bresolin, F.

AU - Terlevich, E.

AU - Melnick, J.

AU - Chavez, R.

PY - 2010/1/1

Y1 - 2010/1/1

N2 - We propose to use alternative cosmic tracers to measure the dark energy equation of state and the matter content of the Universe [w(z) & Ωm]. Our proposed method consists of two components: (a) tracing the Hubble relation using HII galaxies which can be detected up to very large redshifts, z ∼ 4, as an alternative to supernovae type Ia, and (b) measuring the clustering pattern of X-ray selected AGN at a median redshift of ∼ 1. Each component of the method can in itself provide interesting constraints on the cosmological parameters, especially under our anticipation that we will reduce the corresponding random and systematic errors significantly. However, by joining their likelihood functions we will be able to put stringent cosmological constraints and break the known degeneracies between the dark energy equation of state (whether it is constant or variable) and the matter content of the universe and provide a powerful and alternative route to measure the contribution to the global dynamics and the equation of state of dark energy. A preliminary joint analysis of X-ray selected AGN clustering (based on the largest to-date XMM survey; the 2XMM) and the currently largest SNIa sample, the Constitution set (Hicken et al.), using as priors a flat universe and the WMAP5 normalization of the power-spectrum, provides: Ωm 0.27 0.02 and w= -0.96 0.07. Equivalent and consistent results are provided by the joint analysis of X-ray selected AGN clustering and the latest Baryonic Acoustic Oscillation measures, providing: Ωm 0.270.02 and w= -0.970.04.

AB - We propose to use alternative cosmic tracers to measure the dark energy equation of state and the matter content of the Universe [w(z) & Ωm]. Our proposed method consists of two components: (a) tracing the Hubble relation using HII galaxies which can be detected up to very large redshifts, z ∼ 4, as an alternative to supernovae type Ia, and (b) measuring the clustering pattern of X-ray selected AGN at a median redshift of ∼ 1. Each component of the method can in itself provide interesting constraints on the cosmological parameters, especially under our anticipation that we will reduce the corresponding random and systematic errors significantly. However, by joining their likelihood functions we will be able to put stringent cosmological constraints and break the known degeneracies between the dark energy equation of state (whether it is constant or variable) and the matter content of the universe and provide a powerful and alternative route to measure the contribution to the global dynamics and the equation of state of dark energy. A preliminary joint analysis of X-ray selected AGN clustering (based on the largest to-date XMM survey; the 2XMM) and the currently largest SNIa sample, the Constitution set (Hicken et al.), using as priors a flat universe and the WMAP5 normalization of the power-spectrum, provides: Ωm 0.27 0.02 and w= -0.96 0.07. Equivalent and consistent results are provided by the joint analysis of X-ray selected AGN clustering and the latest Baryonic Acoustic Oscillation measures, providing: Ωm 0.270.02 and w= -0.970.04.

UR - http://www.scopus.com/inward/record.url?scp=77954661609&partnerID=8YFLogxK

U2 - 10.1088/1742-6596/222/1/012025

DO - 10.1088/1742-6596/222/1/012025

M3 - Artículo de la conferencia

AN - SCOPUS:77954661609

VL - 222

JO - Journal of Physics: Conference Series

JF - Journal of Physics: Conference Series

SN - 1742-6588

IS - 1

M1 - 012025

ER -