Quantitative photospheric spectral analysis of the Type IIP supernova 2007od

Authors

  • C. Inserra,

    Corresponding author
    1. Dipartimento di Fisica ed Astronomia, Universita’ di Catania, Sezione Astrofisica, Via S.Sofia 78, 95123 Catania, Italy
    2. INAF – Osservatorio Astrofisico di Catania, Via S.Sofia 78, 95123 Catania, Italy
    3. Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019, USA
      E-mail: cosimo.inserra@oact.inaf.it
    Search for more papers by this author
  • E. Baron,

    1. Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019, USA
    2. Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg, Germany
    3. Computational Research Division, Lawrence Berkeley National Laboratory, MS 50F-1650, 1 Cyclotron Road, Berkeley, CA 94720, USA
    Search for more papers by this author
  • M. Turatto

    1. INAF – Osservatorio Astronomico di Trieste, Via Tiepolo 11, 34143 Trieste, Italy
    Search for more papers by this author

E-mail: cosimo.inserra@oact.inaf.it

ABSTRACT

We compare and analyse a time series of spectral observations obtained during the first 30 d of evolution of SN 2007od with the non-local thermodynamic equilibrium code phoenix. Despite some spectroscopic particularities in the Balmer features, this supernova appears to be a normal Type II, and the fits proposed are generally in good agreement with the observations. As a starting point, we have carried out an analysis with the parametrized synthetic spectrum code synow to confirm line identifications and to highlight differences between the results of the two codes. The analysis computed using phoenix suggests the presence of a high-velocity feature in Hβ and an Hα profile reproduced with a density profile steeper than that of the other elements. We also show a detailed analysis of the ions velocities of the six synthetic spectra. The distance is estimated for each epoch with the spectral-fitting expanding atmosphere method. Consistent results are found using all the spectra which give the explosion date of JD 245 4403 (2007 October 29) and a distance modulus μ= 32.2 ± 0.3.

Ancillary