Optical Light Curve of the Type Ia Supernova 1998bu in M96 and the Supernova Calibration of the Hubble Constant Academic Article uri icon


  • We present the UBV(RI)KC light curves of the Type Ia supernova SN 1998bu, which appeared in the nearby galaxy M96 (NGC 3368). M96 is a spiral galaxy in the Leo I group that has a Cepheid-based distance. Our photometry allows us to calculate the absolute magnitude and reddening of this supernova. These data, when combined with measurements of the four other well-observed supernovae with Cepheid-based distances, allow us to calculate the Hubble constant with respect to the Hubble flow defined by the distant Caln/Tololo Type Ia sample. We find a Hubble constant of 63.9 2.2(internal) 3.5(external) km s-1 Mpc-1, consistent with most previous estimates based on Type Ia supernovae. We note that the two well-observed Type Ia supernovae in Fornax, if placed at the Cepheid distance to the possible Fornax spiral NGC 1365, are apparently too faint with respect to the Caln/Tololo sample calibrated with the five Type Ia supernovae with Cepheid distances to the host galaxies.

published proceedings

  • The Astronomical Journal

altmetric score

  • 3

author list (cited authors)

  • Suntzeff, N. B., Phillips, M. M., Covarrubias, R., Navarrete, M., Prez, J. J., Guerra, A., ... Winkler, P. F.

citation count

  • 103

complete list of authors

  • Suntzeff, Nicholas B||Phillips, MM||Covarrubias, R||Navarrete, M||Pérez, JJ||Guerra, A||Acevedo, MT||Doyle, Laurance R||Harrison, Thomas||Kane, Stephen||Long, Knox S||Maza, José||Miller, Scott||Piatti, Andrés E||Clariá, Juan J||Ahumada, Andrea V||Pritzl, Barton||Winkler, P Frank

publication date

  • March 1999