Cosmological constraints from calibrated gamma-ray burst correlation by using DESI 2024 data release
arXiv:2408.02536
Abstract
Recent outcomes by the DESI Collaboration have shed light on a possible slightly evolving dark energy, challenging the standard CDM paradigm. To better understand dark energy nature, high-redshift observations like gamma-ray burst data become essential for mapping the universe expansion history, provided they are calibrated with other probes. To this aim, we calibrate the (or Amati) correlation through model-independent Bézier interpolations of the updated Hubble rate and the novel DESI data sets. More precisely, we provide two Bézier calibrations: i) handling the entire DESI sample, and ii) excluding the point at , criticized by the recent literature. In both the two options, we let the comoving sound horizon at the drag epoch, , vary in the range Mpc. The Planck value is also explored for comparison. By means of the so-calibrated gamma-ray bursts, we thus constrain three dark energy frameworks, namely the standard CDM, the CDM and the CDM models, in both spatially flat and non-flat universes. To do so, we worked out Monte Carlo Markov chain analyses, making use of the Metropolis-Hastings algorithm. Further, we adopt model selection criteria to check the statistically preferred cosmological model finding a preference towards the concordance paradigm only whether the spatial curvature is zero. Conversely, and quite interestingly, the flat CDM and both the cases, flat/non-flat, CDM model, leave evidently open the chance that dark energy evolves at higher redshifts.
15 pages, 7 figures, 8 tables