Brown, E. L. and Marsden, S. C. 
ORCID: https://orcid.org/0000-0001-5522-8887 and Mengel, M. W. ORCID: https://orcid.org/0000-0002-7830-6822 and Jeffers, S. V. and Millburn, I. and Mittag, M. and Petit, P. and Vidotto, A. A. and Morin, J. and See, V. and Jardine, M. and Gonzalez-Perez, J. N. and BCool Collaboration
(2020)
Magnetic field and chromospheric activity evolution of HD 75332: a rapid magnetic cycle in an F star without a hot Jupiter.
Monthly Notices of the Royal Astronomical Society, 501 (3).
pp. 3981-4003.
ISSN 0035-8711
|
Text (Published Version)
Brown2021_pub.pdf Download (12MB) | Preview |
Abstract
Studying cool star magnetic activity gives an important insight into the stellar dynamo and its relationship with stellar properties, as well as allowing us to place the Sun's magnetism in the context of other stars. Only 61 Cyg A (K5V) and τ Boo (F8V) are currently known to have magnetic cycles like the Sun's, where the large-scale magnetic field polarity reverses in phase with the star's chromospheric activity cycles. τ Boo has a rapid ~240 d magnetic cycle, and it is not yet clear whether this is related to the star's thin convection zone or if the dynamo is accelerated by interactions between τ Boo and its hot Jupiter. To shed light on this, we studied the magnetic activity of HD 75332 (F7V) which has similar physical properties to τ Boo and does not appear to host a hot Jupiter. We characterized its long-term chromospheric activity variability over 53 yr and used Zeeman Doppler Imaging to reconstruct the large-scale surface magnetic field for 12 epochs between 2007 and 2019. Although we observe only one reversal of the large-scale magnetic dipole, our results suggest that HD 75332 has a rapid ~1.06 yr solar-like magnetic cycle where the magnetic field evolves in phase with its chromospheric activity. If a solar-like cycle is present, reversals of the large-scale radial field polarity are expected to occur at around activity cycle maxima. This would be similar to the rapid magnetic cycle observed for τ Boo, suggesting that rapid magnetic cycles may be intrinsic to late-F stars and related to their shallow convection zones.
|
Statistics for this ePrint Item |
| Item Type: | Article (Commonwealth Reporting Category C) |
|---|---|
| Refereed: | Yes |
| Item Status: | Live Archive |
| Additional Information: | File reproduced in accordance with the copyright policy of the publisher/author. |
| Faculty/School / Institute/Centre: | Current - Institute for Advanced Engineering and Space Sciences - Centre for Astrophysics (1 Aug 2018 -) |
| Faculty/School / Institute/Centre: | Current - Institute for Advanced Engineering and Space Sciences - Centre for Astrophysics (1 Aug 2018 -) |
| Date Deposited: | 14 Apr 2022 01:10 |
| Last Modified: | 31 May 2022 03:24 |
| Uncontrolled Keywords: | stars: Activity; stars: Individual (HD 75332); stars: Magnetic field |
| Fields of Research (2020): | 51 PHYSICAL SCIENCES > 5101 Astronomical sciences > 510109 Stellar astronomy and planetary systems |
| Socio-Economic Objectives (2020): | 28 EXPANDING KNOWLEDGE > 2801 Expanding knowledge > 280120 Expanding knowledge in the physical sciences |
| Identification Number or DOI: | https://doi.org/10.1093/mnras/staa3878 |
| URI: | http://eprints.usq.edu.au/id/eprint/46750 |
Actions (login required)
 |
Archive Repository Staff Only |