* Astronomy

Title: Quantitative Photospheric Spectral Analysis of the Type IIP Supernova 2007od
Authors: C. Inserra, E. Baron, M. Turatto

We compare and analyse a time series of spectral observations obtained during the first 30 days of evolution of SN 2007od with the non-LTE 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 parameterised 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 H{\beta} and an H{\alpha} 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 6 synthetic spectra. The distance is estimated for each epoch with the Spectral-fitting Expanding Atmosphere Method (SEAM). Consistent results are found using all the spectra which give the explosion date of JD 2454403 (29 October, 2007) and a distance modulus \mu = 32.2 ±0.3.

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