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Chromospheric activities of pre-main-sequence stars

Published online by Cambridge University Press:  23 December 2024

Mai Yamashita Open the ORCID record for Mai Yamashita [Opens in a new window] ,
Yoichi Itoh ,
Yuhei Takagi  and
Yumiko Oasa
Mai Yamashita*
Affiliation:
Nishi–Harima Astronomical Observatory, Center for Astronomy, University of Hyogo, 407-2 Nishigaichi, Sayo, Sayo, Hyogo, Japan
Yoichi Itoh
Affiliation:
Nishi–Harima Astronomical Observatory, Center for Astronomy, University of Hyogo, 407-2 Nishigaichi, Sayo, Sayo, Hyogo, Japan
Yuhei Takagi
Affiliation:
Subaru Telescope, National Astoronomical Observatory of Japan, 650 North A’ohoku Place, Hilo, HI 96720, U.S.A.
Yumiko Oasa
Affiliation:
Faculty of Education, Saitama University, 255 Shimo–Okubo, Sakura, Saitama, Saitama, Japan
*
email: yamashita@nhao.jp
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Abstract

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We investigated chromospheric activities of pre-main-sequence (PMS) stars. First, we studied the Ca II infrared triplet emission lines with Subaru/HDS and other spectroscopic instruments. Most PMS stars have narrow Ca II lines whose intensities are as large as the maximum of the zero-age main-sequence (ZAMS) stars. The chromosphere of PMS stars is suggested to be filled by the Ca II emitting region. Second, we found many faint chromospheric emission lines such as Mg I and Fe I for more than half of the ZAMS stars. Third, we searched the periodic light variation caused by a starspot for the 26 PMS stars. Their TESS light variations and Ca II emission line strengths show the positive correlation, and are located on the extensions of the superflare stars. In summary, PMS stars have very active chromosphere driven by strong dynamo process due to the fast rotation and the long convection timescale.

Keywords

stars: pre-main sequencestars: chromospheresstars: activitytechniques: spectroscopictechniques: photometric
Type
Contributed Paper
Information
Proceedings of the International Astronomical Union , Volume 19 , Symposium S365: Dynamics of Solar and Stellar Convection Zones and Atmospheres , December 2023 , pp. 368 - 374
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Copyright
© The Author(s), 2024. Published by Cambridge University Press on behalf of International Astronomical Union

References

Bailer–Jones, C. A. L., Rybizki, J., Fouesneau, M., Mantelet, G., & Andrae, R. 2018, ApJ., 156, 58 CrossRefGoogle Scholar
Feinstein, A. D., Montet, B. T., Foreman–Mackey, D., et al. 2019, PASP, 131 Google Scholar
Folsom et al. 2018, MNRAS, 474, 4956 CrossRefGoogle Scholar
Fleck, B., Deubner, F.-L., Maier, D., & Schmidt, W. 1994, IAU Symp, 154, 65 Google Scholar
Fukugita, M., Ichikawa, T., Gunn, J. E., et al. 1996, AJ, 111, 1748 CrossRefGoogle Scholar
Gallet, F., & Bouvier, J. 2015, A&A, 577, 1 Google Scholar
Hamann, F., & Persson, S. E. 1992a, Astrophys. J. Suppl., 82, 247 CrossRefGoogle Scholar
Jung, Y. K., & Kim, Y.-C. 2007, J. Astron. Space Sci., 24, 1 CrossRefGoogle Scholar
Linsky, J. L. 2017, Annu Rev Astron Astrophys, 55, 159 CrossRefGoogle Scholar
Marsden, S. C., Carter, B. D., & Donati, J.-F. 2009, MNRAS, 399, 888 CrossRefGoogle Scholar
Neuhauser, R., Strerzik, M. F., Schmitt, J. H. M. M., Wichmann, R., & Krautter, J. 1995, Astron. Astrophys., 297, 391 Google Scholar
Notsu, Y., Honda, S., Maehara, H., et al. 2015, PASJ, 67, 1 Google Scholar
Noyes, R. W., Hamann, F. W., Baliunas, S. L., & Vaughan, A. H. 1984, AJ, 279, 763 Google Scholar
Parker, E. N. 1955, ApJ, 122, 293 CrossRefGoogle Scholar
Rebull, L. M., Stauffer, J. R., Bouvier, J., et al. 2016, AJ, 152, 114 CrossRefGoogle Scholar
Scargle, J. D. 1982, AJ, 263, 835 Google Scholar
Skelly, M. B., Donati, J. F., Bouvier, J., et al. 2010, MNRAS, 403, 159 CrossRefGoogle Scholar
Stelzer, B., Fernandez, M., Costa, V. M., et al. 2003, A&A, 411, 517 Google Scholar
Vernazza, J. E., Avrett, E. H., & Loeser, R. 1981, ApJS, 45, 635 CrossRefGoogle Scholar
Wilson, O. C. 1978, ApJ, 226, 379 CrossRefGoogle Scholar
Yamashita, M., Itoh, Y., & Takagi, Y. 2020, PASJ, 72, 80 CrossRefGoogle Scholar
Yamashita, M., & Itoh, Y. 2022a, PASJ, 74, 557 CrossRefGoogle Scholar
Yamashita, M., Itoh, Y. & Oasa, Y., 2022b, PASJ, 74, 1295 CrossRefGoogle Scholar
Zacharias, N., Finch, C. T., Girard, T. M., et al. 2013, Astrophys. J., 145, 1 Google Scholar