000002093 001__ 2093
000002093 005__ 20160701171658.0
000002093 0247_ $$2DOI$$a10.1093/mnrasl/slv130
000002093 037__ $$aASTROimport-250
000002093 100__ $$aNeiner, C.
000002093 245__ $$aFirst discovery of a magnetic field in a main-sequence δ Scuti star: the Kepler star HD 188774
000002093 260__ $$c2015
000002093 520__ $$aThe Kepler space mission provided a wealth of δ Sct-γ Dor hybrid candidates. While some may be genuine hybrids, others might be misclassified due to the presence of a binary companion or to rotational modulation caused by magnetism and related surface inhomogeneities. In particular, the Kepler δ Sct-γ Dor hybrid candidate HD 188774 shows a few low frequencies in its light and radial velocity curves, whose origin is unclear. In this work, we check for the presence of a magnetic field in HD 188774. We obtained two spectropolarimetric measurements with an Echelle SpectroPolarimetric Device for the Observation of Stars (ESPaDOnS) at Canada-France-Hawaii Telescope. The data were analysed with the least-squares deconvolution (LSD) method. We detected a clear magnetic signature in the Stokes V LSD profiles. The origin of the low frequencies detected in HD 188774 is therefore most probably the rotational modulation of surface spots possibly related to the presence of a magnetic field. Consequently, HD 188774 is not a genuine hybrid δ Sct-γ Dor star, but the first known magnetic main-sequence δ Sct star. This makes it a prime target for future asteroseismic and spot modelling. This result casts new light on the interpretation of the Kepler results for other δ Sct-γ Dor hybrid candidates. 
000002093 700__ $$a Lampens, P.
000002093 773__ $$cL86-L90$$i1$$pMonthly Notices of the Royal Astronomical Society$$v454$$y2015
000002093 85642 $$ahttp://esoads.eso.org/abs/2015MNRAS.454L..86N
000002093 905__ $$apublished in
000002093 980__ $$aREFERD