| 1. |
- Henrichs, Huib F., et al.
(författare)
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Search for the magnetic field of the O7.5 III star ξ Persei
- 2009
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Ingår i: Cosmic Magnetic Fields: From Planets, to Stars and Galaxies, Proceedings of the International Astronomical Union. ; 259, s. 383-384, s. 383-384
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Cyclical wind variability is an ubiquitous but as yet unexplained feature among OB stars. The O7.5 III(n)((f)) star ξ Persei is the brightest representative of this class on the Northern hemisphere. As its prominent cyclical wind properties vary on a rotational time scale (2 or 4 days) the star has been already for a long time a serious magnetic candidate. As the cause of this enigmatic behavior non-radial pulsations and/or a surface magnetic field are suggested. We present a preliminary report on our attempts to detect a magnetic field in this star with high-resolution measurements obtained with the spectropolarimeter Narval at TBL, France during 2 observing runs of 5 nights in 2006 and 5 nights in 2007. Only upper limits could be obtained, even with the longest possible exposure times. If the star hosts a magnetic field, its surface strength should be less than about 300 G. This would still be enough to disturb the stellar wind significantly. From our new data it seems that the amplitude of the known non-radial pulsations has changed within less than a year, which needs further investigation.
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| 2. |
- Henrichs, Huib F., et al.
(författare)
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The magnetic field of the B3V star 16 Pegasi
- 2009
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Ingår i: Proceedings of the International Astronomical Union. ; 259, s. 393-394, s. 393-394
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The slowly pulsating B3V star 16 Pegasi was discovered by Hubrig et al. (2006) to be magnetic, based on low-resolution spectropolarimetric observations with FORS1 at the VLT. We have confirmed the presence of a magnetic field with new measurements with the spectropolarimeters Narval at TBL, France and Espadons at CFHT, Hawaii during 2007. The most likely period is about 1.44 d for the modulation of the field, but this could not be firmly established with the available data set. No variability has been found in the UV stellar wind lines. Although the star was reported once to show Hα in emission, there exists at present no confirmation that the star is a Be star.
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| 3. |
- Wahlgren, Glenn, et al.
(författare)
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Emission Lines in Optical Spectra of He-weak Stars
- 2003
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Ingår i: Magnetic Fields in O, B and A Stars: Origin and Connection to Pulsation, Rotation and Mass Loss (ASP Conference Series ; 305). - 1583811540 ; 305, s. 256-260
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Konferensbidrag (refereegranskat)
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