English

Flat Spectrum Radio Continuum Emission Associated with $\epsilon$ Eridani

Solar and Stellar Astrophysics 2019-01-07 v1

Abstract

We present Very Large Array observations at 33.0 GHz that detect emission coincident with ϵ\epsilon Eridani to within 0."070\rlap.{"}07 (0.2 AU at the distance of this star), with a positional accuracy of 0."050\rlap.{"}05. This result strongly supports the suggestion of previous authors that the quiescent centimeter emission comes from the star and not from a proposed giant exoplanet with a semi-major axis of 1."0\sim1\rlap.{"}0 (3.4 AU). The centimeter emission is remarkably flat and is consistent with optically thin free-free emission. In particular, it can be modeled as a stellar wind with a mass loss rate of the order of 6.6×1011 M yr16.6 \times 10^{-11}~ M_\odot ~yr^{-1}, which is 3,300 times the solar value, exceeding other estimates of this star's wind. However, interpretation of the emission in terms of other thermal mechanisms like coronal free-free and gyroresonance emission cannot be discarded.

Keywords

Cite

@article{arxiv.1901.00903,
  title  = {Flat Spectrum Radio Continuum Emission Associated with $\epsilon$ Eridani},
  author = {Luis F. Rodriguez and Susana Lizano and Laurent Loinard and Miguel Chávez-Dagostino and Timothy S. Bastian and Anthony J. Beasley},
  journal= {arXiv preprint arXiv:1901.00903},
  year   = {2019}
}

Comments

13 pages, 3 figures