• Publications
  • Influence
A BCool magnetic snapshot survey of solar-type stars
We present the results of a major high-resolution spectropolarimetric BCool project magnetic survey of 170 solar-type stars. Surface magnetic fields were detected on 67 stars, with 21 classified asExpand
The Magnetic Fields at the Surface of Active Single G-K Giants
We investigate the magnetic field at the surface of 48 red giants selected as promising for detection of Stokes V Zeeman signatures in their spectral lines. We use the spectropolarimeters Narval andExpand
The magnetic field of Betelgeuse: a local dynamo from giant convection cells?
Context. Betelgeuse is an M supergiant with a complex and extended atmosphere, which also harbors spots and giant granules at its surface. A possible magnetic field could contribute to the mass lossExpand
Discovery of a weak magnetic field in the photosphere of the single giant Pollux
Aims. We observe the nearby, weakly-active single giant, Pollux, in order to directly study and infer the nature of its magnetic field. Methods. We used the new generation spectropolarimetersExpand
Direct observation of magnetic cycles in Sun-like stars
A sample of 19 solar-type stars, probing masses between 0.6 and 1.4 solar mass and rotation periods between 3.4 and 43 days, was regularly observed using the NARVAL spectropolarimeter at TelescopeExpand
Search for surface magnetic fields in Mira stars. First detection in χ Cygni
Context. So far, surface magnetic fields have never been detected on Mira stars. Only recently have the spectropolarimetric capabilities of measuring it via the Zeeman effect become available to us.Expand
A polarity reversal in the large-scale magnetic field of the rapidly rotating sun HD 190771
Aims. We investigate the long-term evolution of the large-scale photospheric magnetic field geometry of the solar-type star HD 190771. With fundamental parameters very close to those of the SunExpand
EK Eridani: the tip of the iceberg of giants which have evolved from magnetic Ap stars
Aims. We observe the slowly-rotating, active, single giant, EK Eri, to study and infer the nature of its magnetic field directly. Methods. We used the spectropolarimeter NARVAL at the TelescopeExpand
The magnetic strip(s) in the advanced phases of stellar evolution - Theoretical convective turnover timescale and Rossby number for low- and intermediate-mass stars up to the AGB at various
Recent spectropolarimetric observations of otherwise ordinary G, K, and M giants revealed localized magnetic strips in the HRD coincident with the regions where the first dredge-up and coreExpand
Magnetic field and convection in the cool supergiant Betelgeuse
We present the outcome of a highly-sensitive search for magnetic fields on the cool supergiant Betelgeuse. A time-series of six circularly-polarized spectra was obtained using the NARVALExpand