First measurement of the magnetic field on FK Com and its relation to the contemporaneous starspot locations
arXiv:0812.0603 · doi:10.1111/j.1365-2966.2008.14263.x
Abstract
In this study we present simultaneous low-resolution longitudinal magnetic field measurements and high-resolution spectroscopic observations of the cool single giant FK Com. The variation of the magnetic field over the rotational period of 2.4 days is compared with the starspot location obtained using Doppler imaging techniques, V-band photometry and V-I colours. The chromospheric activity is studied simultaneously with the photospheric activity using high resolution observations of the Halpha, Hbeta and Hgamma line profiles. Both the maximum (272 +/- 24 G) and minimum (60 +/- 17 G) in the mean longitudinal magnetic field, <Bz>, are detected close to the phases where cool spots appear on the stellar surface. A possible explanation for such a behaviour is that the active regions at the two longitudes separated by 0.2 in phase have opposite polarities.
arXiv comment10 Pages, 11 figures (quality of Figures 7,8 and 10 reduced), accepted for publication in MNRAS
References in corpus (9)
- The large-scale axisymmetric magnetic topology of avery-low-mass fully-convective star
- Measurements of magnetic fields over the pulsation cycle in six roAp stars with FORS1 at the VLT
- Accurate magnetic field measurements of Vega-like stars and Herbig Ae/Be stars
- Preferred sunspot longitudes: Non-axisymmetry and differential rotation
- Surface imaging of HD 199178 (V1794 Cygni)
- Photospheric magnetic field and surface differential rotation of the FK Com star HD 199178
- Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And
- Kinematic frames and "active longitudes": does the Sun have a face?
- Century scale persistence in longitude distribution: in the Sun and in silico
Cited by in corpus (9)
- The Stellar Activity of TRAPPIST-1 and Consequences for the Planetary Atmospheres
- Flip-flops of FK Comae Berenices
- Observing dynamos in cool stars
- Activity on the M star of QS Vir
- Magnetic Structure of Rapidly Rotating FK Comae-Type Coronae
- Study of FK Comae Berenices: VII. Correlating photospheric and chromospheric activity
- Visualization and spectral synthesis of rotationally distorted stars
- Spectropolarimetric follow-up of 8 rapidly rotating, X-ray bright FK Comae candidates
- Surface magnetism of cool giant and supergiant stars