English

Anisotropic Ionizing Illumination from an M-type Pre-main Sequence Star, DM Tau

Solar and Stellar Astrophysics 2023-08-07 v2 Earth and Planetary Astrophysics

Abstract

The powerful, high-energy magnetic activities of young stars play important roles in the magnetohydrodynamics in the innermost parts of the protoplanetary disks. In addition, the associated UV and X-ray emission dictates the photochemistry; moreover, the corona activities can affect the atmosphere of a newborn extra-solar planet. How the UV and X-ray photons are generated, and how they illuminate the disks, are not well understood. Here we report the analyses of the optical and infrared (OIR) photometric monitoring observations and the high angular-resolution centimeter band images of the low-mass (M1 type) pre-main sequence star, DM Tau. We found that the OIR photometric light curves present periodic variations, which is consistent with that the host young star is rotating in the same direction as the natal disk and is hosting at least one giant cold spot. In addition, we resolved that the ionized gas in the DM Tau disk is localized, and its spatial distribution is varying with time. All the present observations can be coherently interpreted, if the giant cold spot is the dominant anisotropic UV and/or X-ray source that illuminates the ambient cone-like region. These results indicate that a detailed theoretical model of the high-energy protostellar emission is essential in the understanding of the space weather around the extra-solar planets and the origin of life.

Keywords

Cite

@article{arxiv.2306.09013,
  title  = {Anisotropic Ionizing Illumination from an M-type Pre-main Sequence Star, DM Tau},
  author = {Yuka Terada and Hauyu Baobab Liu and David Mkrtichian and Jinshi Sai and Mihoko Konishi and Ing-Guey Jiang and Takayuki Muto and Jun Hashimoto and Motohide Tamura},
  journal= {arXiv preprint arXiv:2306.09013},
  year   = {2023}
}

Comments

13 pages, 6 figures

R2 v1 2026-06-28T11:05:47.670Z