Zeeman-Doppler imaging of five young solar-type stars

Abstract

The magnetic activity of the Sun changes with the solar cycle. Similar cycles are found in other stars as well, but their details are not known to a similar degree. Characterising stellar magnetic cycles is important for the understanding of the stellar and solar dynamos that are driving the magnetic activity. We present spectropolarimetric observations of five young, solar-type stars, and compare them to previous observations, with the aim to identify and characterise stellar equivalents of the solar cycle. We use Zeeman-Doppler imaging (ZDI) to map the surface magnetic field and brightness of our targets. The magnetic field is decomposed into spherical harmonic expansions, from which we report the strengths of the axisymmetric vs. non-axisymmetric, and poloidal vs. toroidal components, and compare them to the Rossby numbers of the stars. We present five new ZDI-maps of young, solar-type stars from Dec 2017. Of special interest is the case of V1358 Ori, that has gone through a polarity reversal between our observations and earlier ones. A less evident polarity reversal might also have occurred in HD 35296. There is a preference for more axisymmetric field, and possibly more toroidal field, for the more active stars with lower Rossby number, but a larger sample should be studied to draw any strong conclusions from this. For most of the individual stars, the amounts of toroidal and poloidal field have stayed on similar levels as in earlier observations. We find evidence for a magnetic polarity reversal having occurred in V1358 Ori. \c{hi}1 Ori could be an interesting target for future observations, with a possible short magnetic cycle of a few years. The correlation between the brightness maps and the magnetic field is mostly poor, which could indicate the presence of small-scale magnetic features of different polarities, that cancel each other out, and are not resolved in our maps.

References in corpus (38)

• New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey
• The Geneva-Copenhagen Survey of the Solar neighbourhood III. Improved distances, ages, and kinematics
• Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Northern Sample I
• Late-type stars members of young stellar kinematic groups - I. Single stars
• Stellar magnetism: empirical trends with age and rotation
• Least squares deconvolution of the stellar intensity and polarization spectra
• Structure and Evolution of Nearby Stars with Planets II. Physical Properties of ~1000 Cool Stars from the SPOCS Catalog
• The Tucana/Horologium, Columba, AB Doradus, and Argus Associations: New Members and Dusty Debris Disks
• Fundamental parameters and infrared excesses of Hipparcos stars
• Magnetic cycles of the planet-hosting star tauBootis
• Rotation, differential rotation, and gyrochronology of active Kepler stars
• Magnetic cycles of the planet-hosting star Tau Bootis: II. a second magnetic polarity reversal
• Lithium abundances for 185 main-sequence stars - Galactic evolution and stellar depletion of lithium
• Magnetic field topology of the unique chemically peculiar star CU Virginis
• A small survey of the magnetic fields of planet-host stars
• The connection between stellar activity cycles and magnetic field topology
• A solar-like magnetic cycle on the mature K-dwarf 61 Cyg A (HD 201091)
• Hidden magnetic fields of young suns
• Differential rotation in rapidly rotating F-stars
• Activity trends in young solar-type stars
• The Evolving Magnetic Topology of $\tau$ Boötis
• Estimating activity cycles with probabilistic methods II. The Mount Wilson Ca H&K data
• Transition from axi- to nonaxisymmetric dynamo modes in spherical convection models of solar-like stars
• Magnetic fields on young, moderately rotating Sun-like stars - I: HD~35296 and HD~29615
• Magnetic fields of young solar twins
• The relation between stellar magnetic field geometry and chromospheric activity cycles II: The rapid 120 day magnetic cycle of Tau Bootis
• Direct evidence of a full dipole flip during the magnetic cycle of a sun-like star
• Common dynamo scaling in slowly rotating young and evolved stars
• The relation between stellar magnetic field geometry and chromospheric activity cycles I: The highly variable field of Epsilon Eridani at activity minimum
• Zeeman-Doppler imaging of active young solar type stars
• The Evolution of Dusty Debris Disks Around Solar Type Stars
• Starspot activity of HD 199178. Doppler images from 1994--2017
• Topological changes in the magnetic field of LQ Hya during an activity minimum
• Magnetic field and chromospheric activity evolution of HD75332: a rapid magnetic cycle in an F star without a hot Jupiter
• Rotational dependence of turbulent transport coefficients in global convective dynamo simulations of solar-like stars
• Time evolution of magnetic activity cycles in young suns: The curious case of kappa Ceti
• A Knee-Point in the Rotation-Activity Scaling of Late-type Stars with a Connection to Dynamo Transitions
• Magnetic activity of the young solar analogue V1358 Ori

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