I want information on:

Information for:

NAM2012 - All Presentation Details

Record 732 of 756

First | Previous | Next | Last | All  

Morphological changes in the circumstellar environment of V Hya

Author: Foteini Lykou

Jodrell Bank Centre for Astrophysics

Co-Authors: A.A. Zijlstra (Jodrell Bank Centre for Astrophysics); P.G. Tuthill (University of Sydney)

Session: STA2: Binary Stars: Duplicity is Everywhere

Presentation type: Talk      11:00  Friday 30th 10:00-11:15 


The process of stellar mass loss and the shaping of ejecta in AGB stars is a key point in understanding stellar evolution. The transformation of the stellar ejecta during/after the end of the AGB from spherically symmetric shells into asymmetric structures has been attributed to magnetic fields and binarity. These mechanisms can shape the ejecta into asymmetric nebulae, accretion disks, circumbinary disks/torii, dense spirals and jets. Here we present the influence of binarity on the peculiar variable V Hya, a C-rich giant currently transiting from AGB to post-AGB with an unknown companion, a molecular bipolar jet and a torus. We have resolved the circumbinary dusty structure of V Hya in the near-infrared with the means of aperture masking interferometry, a novel technique that transforms a single-dish optical telescope into an interferometer that allows the acquisition of diffraction-limited images. Our findings provide further constraints on the binary's orbit and mass ratio from the morphological changes of the circumstellar environment (possible detection of an orbiting, dusty "clump" associated with the companion) and the variability of the central component over several epochs.

First | Previous | Next | Last | All