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In the context of the high resolution, high signal-to-noise ratio, high sensitivity, spectropolarimetric survey BritePol, which complements observations by the BRITE constellation of nanosatellites for asteroseismology, we are looking for and measuring the magnetic field of all stars brighter than V=4. In this paper, we present circularly polarised spectra obtained with HarpsPol at ESO in La Silla (Chile) and ESPaDOnS at CFHT (Hawaii) for 3 hot evolved stars: $iota$ Car, HR 3890, and $epsilon$ CMa. We detected a magnetic field in all 3 stars. Each star has been observed several times to confirm the magnetic detections and check for variability. The stellar parameters of the 3 objects were determined and their evolutionary status was ascertained employing evolution models computed with the Geneva code. $epsilon$ CMa was already known and is confirmed to be magnetic, but our modeling indicates that it is located near the end of the main sequence, i.e. it is still in a core hydrogen burning phase. $iota$ Car and HR 3890 are the first discoveries of magnetic hot supergiants located well after the end of the main sequence on the HR diagram. These stars are probably the descendants of main sequence magnetic massive stars. Their current field strength (a few G) is compatible with magnetic flux conservation during stellar evolution. These results provide observational constraints for the development of future evolutionary models of hot stars including a fossil magnetic field.
Magnetic confinement of stellar winds leads to the formation of magnetospheres, which can be sculpted into Centrifugal Magnetospheres (CMs) by rotational support of the corotating plasma. The conditions required for the CMs of magnetic early B-type s
In A- and late B-type stars, strong magnetic fields are always associated with Ap and Bp chemical peculiarities. However, it is not clear at what point in a stars evolution those peculiarities develop. Strong magnetic fields have been observed in pre
We report on the status of our spectropolarimetric observations of massive stars. During the last years, we have discovered magnetic fields in many objects of the upper main sequence, including Be stars, beta Cephei and Slowly Pulsating B stars, and
A significant fraction of massive main-sequence stars show strong, large-scale magnetic fields. The origin of these fields, their lifetimes, and their role in shaping the characteristics and evolution of massive stars are currently not well understoo
It is now well-known that the surface magnetic fields observed in cool, lower-mass stars on the main sequence (MS) are generated by dynamos operating in their convective envelopes. However, higher-mass stars (above 1.5 Msun) pass their MS lives with