Context. As type Ia supernova cosmology transitions from a statistics-dominated to a systematics-dominated era, it is crucial to understand the remaining unexplained uncertainties that affect their luminosity, such as those stemming from astrophysical biases. Type Ia supernovae are standardisable candles whose absolute magnitude reaches a scatter of typically 0.15 mag when empirical correlations with their light-curve stretch and colour and with their environmental properties are accounted for. Aims. We investigat…

Context. Type Ia supernova (SN Ia) cosmology studies will soon be dominated by systematic, uncertainties, rather than statistical ones. Thus, it is crucial to understand the unknown phenomena potentially affecting their luminosity that may remain, such as astrophysical biases. For their accurate application in such studies, SN Ia magnitudes need to be standardised; namely, they must be corrected for their correlation with the light-curve width and colour. Aims. Here, we investigate how the standardisation procedur…

Measuring the growth rate of large-scale structures ( f ) as a function of redshift has the potential to break degeneracies between modified gravity and dark energy models, when combined with expansion-rate probes. Direct estimates of peculiar velocities of galaxies have attracted interest as a means of estimating fσ 8 . In particular, field-level methods can be used to fit the field nuisance parameter along with cosmological parameters simultaneously. This article aims to provide the community with a unified fram…

Abstract The measurement of Type Ia supernovae magnitudes provides cosmological distances, which constrain dark energy parameters. Current and upcoming large photometric surveys require improved photometric calibration precision to reduce systematic uncertainties in cosmological constraints. The StarDICE experiment aims to establish accurate broadband flux references for these surveys, targeting sub-percent precision in magnitude measurements. Achieving this requires precise filter bandpass measurements for both S…

B. Carreres et al.