2009

Hubble Residuals of Nearby Type Ia Supernovae Are Correlated with Host Galaxy Masses

Kelly, Patrick L., Hicken, Malcolm, Burke, David L. et al.

Understand

From Sloan Digital Sky Survey u'g'r'i'z' imaging, we estimate the stellar masses of the host galaxies of 70 low redshift SN Ia (0.015 < z < 0.08) from the hosts' absolute luminosities and mass-to-light ratios.

  • These nearby SN were discovered largely by searches targeting luminous galaxies, and we find that their host galaxies are substantially more massive than the hosts of SN discovered by the flux-limited Supernova Legacy Survey.
  • Testing four separate light curve fitters, we detect ~2.5{\sigma} correlations of Hubble residuals with both host galaxy size and stellar mass, such that SN Ia occurring in physically larger, more massive hosts are ~10% brighter after light curve correction.
  • The Hubble residual is the deviation of the inferred distance modulus to the SN, calculated from its apparent luminosity and light curve properties, away from the expected value at the SN redshift.

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