Open AccessHigh levels of surface differential rotation on the young G0 dwarf HD 171488 ★
Author(s) -
Jeffers S. V.,
Donati J.F.
Publication year - 2008
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2008.13695.x
Subject(s) - physics , differential rotation , polar , astrophysics , zeeman effect , brightness , latitude , equator , rotation (mathematics) , starspot , telescope , surface brightness , magnetic field , astronomy , stars , geometry , mathematics , quantum mechanics , galaxy
We present high‐resolution images of the young, rapidly rotating G0 dwarf HD 171488, using both Stokes I and Stokes V data. The observations were secured with the MuSiCoS spectropolarimeter at Telescope Bernard Lyot from 2005 May 31 to June 10. The photospheric surface brightness distributions show a strong and slightly decentred polar cap that dominates over weak high‐ and low‐latitude spot features. The large‐scale magnetic field topology shows a strong ring of anticlockwise azimuthal field with a latitudinal dependence on polarity and large regions of radial field with negative polarity at all latitudes. Using the good phase coverage of our data, we measure the differential rotation on HD 171488. The results indicate that the equator laps the pole every 12 days for brightness data and 13 days for magnetic data, which is the highest measurement of differential rotation obtained using Zeeman–Doppler imaging techniques.