A short and sudden increase of the magnetic field strength and the accompanying spectral variability in the O9.7 V star HD 54879
作者： S Hubrig , M Küker , S P Järvinen , A F Kholtygin , M Schöller
DOI: 10.1093/MNRAS/STZ198
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摘要: Only eleven O-type stars have been confirmed to possess large-scale organized magnetic fields. The presence of a -600G longitudinal field in the O9.7V star HD54879 with lower limit dipole strength ~2kG, was discovered few years ago framework ESO large program "B-fields OB stars". Our FORS2 spectropolarimetric observations from 2017 October 4 2018 February 21 reveal short and long-term spectral variability gradual decrease about -300G down -90G. Surprisingly, we discover on night 17 sudden, short-term increase measure -833G. inspection spectrum acquired during observed indicates very strong change appearance significantly photospheric temperature radial velocity by several 10km/s. Different scenarios are discussed an attempt interpret our observations. measurements indicate that is member long-period binary.
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