ZTF SN Ia DR2: Peculiar velocities impact on the Hubble diagram

Understand

SNe Ia are used to determine the distance-redshift relation and build the Hubble diagram.

• Neglecting their host-galaxy peculiar velocities (PVs) may bias the measurement of cosmological parameters.
• The smaller the redshift, the larger the effect is.
• We use realistic simulations of SNe Ia observed by the Zwicky Transient Facility (ZTF) to investigate the effect of different methods to take into account PVs.