GRB Hubble diagram and constraints on a Λ(t)CDM model

Abstract

In previous papers, a cosmological model with constant-rate particle creation and vacuum term decaying linearly with the Hubble parameter was shown to lead to a good concordance when tested against precise observations: the position of the first peak in the spectrum of anisotropies of the cosmic microwave background (CMB), the Hubble diagram for supernovas of type Ia (SNe Ia), the distribution of large-scale structures (LSS) and the distance to the baryonic acoustic oscillations (BAO). That model has the same number of parameters as the spatially flat standard model and seems to alleviate some observational/theoretical tensions appearing in the later. In this letter we complement those tests with 109 gamma ray bursters (GRB), 59 of them with redshifts above $z=1.4$, which permits to extend the Hubble diagram to redshifts up to $z\approx 8$. For the calibration of the 50 GRBs with $z<1.4$ we use the 288 supernovas of the Sloan Digital Sky Survey (SDSS) project, calibrated with the MLCS2k2 fitter, less model-dependent than other samples like Union2. Our results show a good concordance with the previous tests and, again, less tensions between SNe Ia and GRB best fits as compared to the standard model.

7 pages, 8 figures, MNRAS accepted

References in corpus (10)

• Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
• Improved Dark Energy Constraints from ~100 New CfA Supernova Type Ia Light Curves
• Improved Distances to Type Ia Supernovae with Multicolor Light Curve Shapes: MLCS2k2
• SNLS3: Constraints on Dark Energy Combining the Supernova Legacy Survey Three Year Data with Other Probes
• The Hubble Diagram to Redshift >6 from 69 Gamma-Ray Bursts
• The shape of the SDSS DR5 galaxy power spectrum
• A Cosmology-Independent Calibration of Gamma-Ray Burst Luminosity Relations and the Hubble Diagram
• Gamma Ray Bursts
• Observational constraints on late-time Lambda(t) cosmology
• Evolution of density perturbations in decaying vacuum cosmology

Cited by in corpus (10)

• Measuring cosmological parameters with Gamma-Ray Bursts
• Observational tests of non-adiabatic Chaplygin gas
• Model-independent distance calibration of high-redshift gamma-ray bursts and constrain on the $\Lambda$CDM model
• Constraining the Anisotropy of the Universe from Supernovae and Gamma-ray Bursts
• Non-adiabatic Chaplygin gas
• On dark degeneracy and interacting models
• Improving sampling and calibration of GRBs as distance indicators
• Are long gamma-ray bursts standard candles?
• Large scale structure and ISW effect in decaying vacuum cosmology
• Number Counts and Dynamical Vacuum Cosmologies