SIMBAD references

We use a nearly complete sample of gamma-ray bursts (GRBs) detected by the Swift satellite to study the correlations between the spectral peak energy E_peak of the prompt emission, the isotropic energetics E_iso and the isotropic luminosity L_iso. This GRB sample is characterized by a high level of completeness in redshift (90 per cent). This allows us to probe in an unbiased way the issue related to the physical origin of these correlations against selection effects. We find that one burst, GRB 061021, is an outlier to the E_peak–E_isocorrelation. Despite this case, we find strong E_peak–E_iso and E_peak–L_iso correlations for the bursts of the complete sample. Their slopes, normalizations and dispersions are consistent with those found with the whole sample of bursts with measured redshift and E_peak. This means that the biases present in the total sample commonly used to study these correlations do not affect their properties. Finally, we also find no evolution with redshift of the E_peak–E_iso and E_peak–L_isocorrelations.