New null diagnostic customized for reconstructing the properties of dark energy from baryon acoustic oscillations data
Abstract
Baryon acoustic oscillations (BAO) provide an important standard ruler which can be used to probe the recent expansion history of our Universe. We show how a simple extension of the Om diagnostic, which we call Om3, can combine standard ruler information from BAO with standard candle information from type Ia supernovae (SNIa) to yield a powerful novel null diagnostic of the cosmological constant hypothesis. A unique feature of Om3 is that it requires minimal cosmological assumptions since its determination does not rely upon prior knowledge of either the current value of the matter density Ω0m and the Hubble constant H0 or the distance to the last scattering surface. Observational uncertainties in these quantities, therefore, do not affect the reconstruction of Om3. We reconstruct Om3 using the Union 2.1 SNIa data set and BAO data from SDSS, WiggleZ and 6dFGS. Our results are consistent with dark energy being the cosmological constant. We show how Om and Om3 can be used to obtain accurate model-independent constraints on the properties of dark energy from future data sets such as BigBOSS.
- Publication:
-
Physical Review D
- Pub Date:
- November 2012
- DOI:
- 10.1103/PhysRevD.86.103527
- arXiv:
- arXiv:1205.2870
- Bibcode:
- 2012PhRvD..86j3527S
- Keywords:
-
- 98.80.-k;
- Cosmology;
- Astrophysics - Cosmology and Extragalactic Astrophysics
- E-Print:
- 9 pages, 4 figures, discussions extended, results unchanged, matches the final version published in PRD