Ia型超新星标准化对局部光度加权年龄的环境依赖性

本文探讨了Ia型超新星标准化光度与宿主星系环境之间的物理联系。研究发现，局部光度加权年龄比全局质量更能解释超新星光度的变化，这为提高宇宙学距离测量的精度提供了新视角。

arXiv:2607.09199v2 Announce Type: replace Abstract: Context. The dependence of Type Ia supernova (SNe Ia) standardized luminosity on host galaxy properties constitutes a significant systematic error in cosmology. However, the widely used empirical mass step, acting as an indirect global proxy, obscures the direct physical link to the progenitor environment, thereby limiting the precision of SNe Ia luminosity standardization. Aims. We investigate the fundamental origin of these dependencies by comparing local luminosity-weighted age (LWA) with global mass, testing whether the mass step is a proxy for progenitor age. Methods. Using SDSS-MaNGA Pipe3D, we measure local LWA within a 1 kpc aperture for 56 SNe Ia and perform a joint likelihood analysis to separate the effects of local age and mass on Hubble residuals. Results. SNe Ia in younger environments are significantly fainter than those in older environments, showing an age step of 0.163 mag (5.2-sigma) after standardization. Although global and local mass steps are initially detected (0.071 mag, 2.0-sigma and 0.087 mag, 2.4-sigma, respectively), both become insignificant after accounting for age. The global mass step decreases to 0.028 mag (0.9-sigma), while the age step remains 0.156 mag (4.9-sigma). Similarly, the local mass step decreases to 0.012 mag (0.3-sigma), whereas the age