A Simple Mean-Field Diagnostic from Stokes V Spectra. Issue Volume 9:Issue S307(2014) (23rd January 2015)

• Record Type: Journal Article
• Authors: Gayley, K. G.; Owocki, S. P.
• Editors: Meynet, Georges; Georgy, Cyril; Groh, José; Stee, Philippe
• Is Part Of: Proceedings of the International Astronomical Union. Volume 9:Issue S307(2014)
• Page Start: 375
• Page End: 376
• Publication Date: 2015-01-23
• Subjects: line:profiles, -- magnetic fields, -- techniques: polarimetric; Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921314007145
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: It is shown that the diagnostics from an observed circularly polarized line in a rapidly rotating star are directly interpretable, not in terms of the observed Stokes V profiles, but in terms of its antiderivative with respect to wavelength (in velocity units if preferred). This also leads to a new mean-field diagnostic that is just as easily obtained as the standard "center of gravity" approach, and is less susceptible to cancellation if the line-of-sight field changes sign over the face of the star.