Late-Time Spectral Evolution of the Type-II Supernova 1990E in NGC1035

Gomez-Velarde, G.; Lopez, R.
Referencia bibliográfica

Monthly Notices of the Royal Astronomical Society, Vol. 263, NO. 3/AUG1, P. 767, 1993

Fecha de publicación:
8
1993
Número de autores
2
Número de autores del IAC
1
Número de citas
3
Número de citas referidas
3
Descripción
We present low-resolution spectra obtained from 5 to 11 months after the discovery of the Type II supernova 1990E in NGC 1035. We analyse the evolution of the Hα feature and discuss the late-time luminosity- powering source through the evolution of the Hα flux. Whatever the SN 1990E photometric subclass, the shape of the Hα profile in these spectra (a relatively weak absorption trough) and its appearance in a near-maximum spectrum (very broad emission with secondary narrow emission components superimposed) are reminiscent of the characteristics of some peculiar events reported by Schlegel or even of some supernova events that have been preceded by a mass-loss episode (such as Supernova 1979C), and this Hα profile seems to be different from those displayed by some typical Type II-P supernovae (such as 1969L, 1973R or 19861) at the same phases. The evolution of the Hα flux points to extra late-time luminosity relative to that derived from a radioactive model. According to Chugai's models, this extra energy could be released in the interaction between the supernova ejecta and the pre-supernova wind.