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Probing the dark energy with quasar clustering
M O Calvão1, J R T de Mello Neto, I Waga
1Universidade Federal do Rio de Janeiro, Instituto de Física, CEP 21945-970 Rio de Janeiro, RJ, Brazil.
Physical Review Letters
|February 28, 2002
Summary
The Alcock-Paczyński test using quasar clustering effectively probes cosmological parameters like density and equation of state. This method, accounting for peculiar velocities, provides valuable insights complementary to other cosmological tests.
Area of Science:
- Cosmology
- Astrophysics
- Statistical Analysis
Background:
- The Alcock-Paczyński test is a standard ruler method used in cosmology.
- Quasar clustering provides a unique dataset for cosmological investigations.
- Understanding the universe's expansion and composition requires precise parameter estimation.
Purpose of the Study:
- To evaluate the Alcock-Paczyński test's efficacy in constraining cosmological parameters using quasar clustering.
- To investigate the impact of peculiar velocities on the test's performance.
- To compare the test's capabilities with existing and future cosmological probes.
Main Methods:
- Monte Carlo simulations were employed to model quasar clustering.
- The correlation function was analyzed, incorporating the effects of peculiar velocities.
- Confidence contours were derived for key cosmological parameters: Omega(m0), Omega(x0), and w.
Main Results:
- The Alcock-Paczyński test, applied to quasar clustering, proves powerful for probing cosmological density and equation of state parameters.
- For the cosmological constant case (w = -1), the test is highly sensitive to Omega(m0)-Omega(Lambda0), complementing cosmic microwave background data.
- In the spatially flat case, the test shows competitiveness and complementarity with future supernova and galaxy number count surveys.
Conclusions:
- The Alcock-Paczyński test, combined with quasar clustering data and peculiar velocity corrections, is a robust cosmological probe.
- This method offers valuable constraints on dark energy and matter density.
- It serves as an important tool for future cosmological model testing and refinement.
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