English

HD 4915: A Maunder Minimum Candidate

Solar and Stellar Astrophysics 2018-08-22 v1

Abstract

We study the magnetic activity cycle of HD 4915 using the \ion{Ca}{2} H \& K emission line strengths measured by Keck I/HIRES spectrograph. The star has been observed as a part of California Planet Search Program from 2006 to present. We note decreasing amplitude in the magnetic activity cycle, a pattern suggesting the star's entry into a Magnetic Grand Minimum (MGM) state, reminiscent of the Sun's Maunder and Dalton Minima. We recommend further monitoring of the star to confirm the grand minimum nature of the dynamo, which would provide insight into the state of the Sun's chromosphere and the global magnetic field during its grand minima. We also recommend continued observations of H \& K emission lines, and ground or space based photometric observations to estimate the sunspot coverage.

Cite

@article{arxiv.1801.09650,
  title  = {HD 4915: A Maunder Minimum Candidate},
  author = {Shivani P. Shah and Jason T. Wright and Howard Isaacson and Andrew Howard and Jason L. Curtis},
  journal= {arXiv preprint arXiv:1801.09650},
  year   = {2018}
}

Comments

To be submitted to AAS Journals; comments welcome

R2 v1 2026-06-23T00:01:52.597Z