National University of Ireland, Galway
|Title (1st Abstract)||
The previous nebulous incarnations of type Ia supernovae
NAtional University of Ireland, Galway
Dr. Matt Redman, Dr. Panos Boumis
10. SNe and SNRs with circumstellar interactions
There have been extensive efforts employed in identifying the progenitors of supernovae (Wang & Han 2012). Here we explore a layout of a simplified binary evolution track following such a system from planetary nebula and then on through classical, recurrent and/or symbiotic nova systems up to their final explosive event.
By investigating the supernova precursor stages, we can gain insight on the environment in which these energetic events unravel and whether their observed outburst magnitudes may be inclination dependent. Bipolar planetary nebulae, classical & recurrent/symbiotic novae and type Ia supernovae are all linked to binaries that contain at least one white dwarf. Binary evolution is still poorly understood, but it is probable that the evolutionary sequence of a certain mass
In the lead up to a type Ia supernova, a classical nova producing system will outburst on shorter recurrence timescales until its final event. This hints at the shear amount of debris surrounding a supernovae Ia at outburst. The material deposited by the previous phases of evolution has been, in general, subject to shaping mechanisms. Some of the surrounding material from the planetary nebula phase (Vexp < 100 km/s), will be more strongly shaped than material from a faster nova event (Vexp 300 – 3000 km/s), because the orbital motion of the pair is thought to strongly influence the structure of the expanding shell during the common-envelope phase. There are about 35 nova episodes in the galaxy per year and they evolve on human timescales, making these old nova shells excellent probes for many unsolved astrophysical problems including clumping, dust formation, shock interactions with CSM/ISM and shaping.
Through a variety of observational techniques from deep imaging to spectroscopy and polarimetry as well as chemical and morpho-kinematic modelling, an attempt at understanding the true nature of the late-lifetimes of these cosmologically important systems are explored.