The determination of the rotation period and magnetic field geometry of the strongly magnetic roAp star HD154708

Abstract

We obtained thirteen spectropolarimetric observations of the strongly magnetic rapidly oscillating Ap star HD154708 over three months with the multi-mode instrument FORS1, installed at the 8-m Kueyen telescope of the VLT. These observations have been used for the determination of the rotation period of P=5.3666+-0.0007d. Using stellar fundamental parameters and the longitudinal magnetic field phase curve, we briefly discuss the magnetic field geometry. The star is observed nearly pole-on and the magnetic field geometry can be described by a centred dipole with a surface polar magnetic field strength B_d between 26.1 and 28.8kG and an inclination of the magnetic axis to the rotation axis in the range 22.5deg to 35.5deg.

6 pages, 4 figures, accepted for publication in MNRAS

References in corpus (3)

• Discovery of 17 new sharp-lined Ap stars with magnetically resolved lines
• On mode conversion and wave reflection in magnetic Ap stars
• Heavy Calcium in CP Stars

Cited by in corpus (8)

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• On the consistency of magnetic field measurements of Ap stars: lessons learned from the FORS1 archive
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• On the understanding of pulsations in the atmosphere of roAp stars: phase diversity and false nodes
• Magnetic stars from a FEROS cool Ap star survey
• Line identification in high-resolution, near-infrared CRIRES spectra of chemically peculiar and Herbig Ae stars
• Understanding the angular momentum evolution of T Tauri and Herbig Ae/Be stars
• Magnetic properties of three cool CP stars with strong fields