Evidence of a Mira-like tail and bow shock about the semi-regular variable V CVn from four decades of polarization measurements.

Creator(s)

Hilding Neilson, East Tennessee State University
Richard Ignace, East Tennessee State UniversityFollow
Beverly Smith, East Tennessee State UniversityFollow
Gary Henson, East Tennessee State UniversityFollow
Alyssa Adams, Arizona State University

Document Type

Article

Publication Date

8-25-2014

Description

Polarization is a powerful tool for understanding stellar atmospheres and circumstellar environments. Mira and semi-regular variable stars have been observed for decades and some are known to be polarimetrically variable, however, the semi-regular variable V Canes Venatici displays an unusually large, unexplained amount of polarization. We present ten years of optical polarization observations obtained with the HPOL instrument, supplemented by published observations spanning a total interval of about forty years for V CVn. We find that V CVn shows large polarization variations ranging from 1 - 6%. We also find that for the past forty years the position angle measured for V CVn has been virtually constant suggesting a long-term, stable, asymmetric structure about the star. We suggest that this asymmetry is caused by the presence of a stellar wind bow shock and tail, consistent with the star's large space velocity.

Copyright Statement

Reproduced with permission from Astronomy & Astrophysics, Copyright © ESO 2014.

Citation Information

Hilding R. Neilson, Richard Ignace, Beverly J. Smith, Gary Henson, and Alyssa M. Adams. "Evidence of a Mira-like tail and bow shock about the semi-regular variable V CVn from four decades of polarization measurements." Astronomy & Astrophysics 568 (2014): A88.
DOI: 10.1051/0004-6361/201424037
Available at: http://works.bepress.com/richard_ignace/9