On the relationship between Type Ia supernova luminosity and host-galaxy properties

A string of recent studies has debated the exact form and physical origin an evolutionary trend between peak luminosity Type Ia supernovae (SNe Ia) properties galaxies that host them. We shed new light on discussion by presenting analysis ~200 low-redshift SNe in which we measure separation Hubble residuals (HR; as probes luminosity) two host-galaxy morphological types. show this can test predictions made recently proposed models, using independently empirically determined distribution each type host-property space. Our results are partially consistent with HR--age slope, but find significant scatter from different galaxy catalogues. The inconsistency age illuminates issue current debate was not obvious long-discussed mass models: HR--host-property models strongly dependent methods employed to determine properties. While our demonstrate difficulty constructing a universal model for proxy environment, indeed identify trends mass, age, morphology, HR values, encouraging (or requiring, if such be accounted cosmological studies) further investigation.