Cosmology Seminar- Type Ia supernova in the near-infrared: from explosion to cosmology

Type Ia supernovae (SNe Ia) are well-known for being precise distance indicators in the local Universe. However, despite their use in cosmology, key questions regarding their progenitor systems, explosion mechanisms, and intrinsic diversity remain unresolved. Near-infrared (NIR) observations of SNe Ia offer unique advantages, such as reduced dust extinction and uniform peak luminosity, while also offering insights into the internal composition and structure of their explosions. In this talk, I present a compilation of SNe Ia from various surveys and the literature, with well-sampled NIR light curves, and analyse their variability through Principal Component Analysis (PCA). Theoretical models and correlations between PCA coefficients and light-curve parameters are used for identifying the dominant physical properties, such as Nickel mass and metallicity, behind their variability around secondary NIR peak. Additionally, the potential for standardising SNe Ia in the NIR to improve their precision as distance indicators is explored.