Type Ia Supernovae standardisation: from ZTF to LSST

Speaker: Madeleine Ginolin (IoA & KICC)
Series: Institute of Astronomy Seminars
Also open online: the joining details are on the talk's page.

Type Ia Supernovae (SNe Ia) are one of the key probes of current cosmological analyses, as they provide precise distance measurements up to a redshift of z~1.2. However, they can only be used if the natural scatter of their luminosity is reduced using a process called standardisation. This process exploits empirical correlations of SN properties with their absolute magnitude.

In recent years, the Zwicky Transient Facility observed more than 3,000 SNe, allowing for robust population studies of SNe Ia. I will discuss new results on standardisation found with the ZTF sample, focusing on the so-called "mass step", or the dependence of SN Ia magnitudes on their astrophysical environment. I will then briefly discuss the implications of these findings on measurements of the dark energy equation of state parameter w, and what LSST can bring to the picture.