The B Fields in OB Stars (BOB) Survey

Abstract

The B fields in OB stars (BOB) survey is an ESO large programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. As of July 2014, a total of 98 objects were observed over 20 nights with FORS2 and HARPSpol. Our preliminary results indicate that the fraction of magnetic OB stars with an organised, detectable field is low. This conclusion, now independently reached by two different surveys, has profound implications for any theoretical model attempting to explain the field formation in these objects. We discuss in this contribution some important issues addressed by our observations (e.g., the lower bound of the field strength) and the discovery of some remarkable objects.

arXiv commentTo appear in proceedings of IAU Symposium 307, New Windows on Massive Stars (Geneva, June 2014)

References in corpus (7)

• Binary interaction dominates the evolution of massive stars
• Magnetic fields of non-degenerate stars
• A fossil origin for the magnetic fields of A-stars and white dwarfs
• Dynamical Simulations of Magnetically Channeled Line-Driven Stellar Winds: III. Angular Momentum Loss and Rotational Spindown
• The Most Magnetic Stars
• On the incidence of magnetic fields in slowly-pulsating B, Beta Cephei and B-type emission line stars
• New magnetic field measurements of beta Cephei stars and Slowly Pulsating B stars

Cited by in corpus (9)

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• Magnetically Confined Wind Shocks in X-rays - a Review
• New observations of NGC 1624-2 reveal a complex magnetospheric structure and underlying surface magnetic geometry
• Ultraviolet Line Profiles of Slowly Rotating Massive Star Winds Using the "Analytic Dynamical Magnetosphere" Formalism
• Confirmation of xi^1 CMa's ultra-slow rotation: magnetic polarity reversal and a dramatic change in magnetospheric UV emission lines
• Distorted surfaces of magnetic helium-peculiar stars: An application to a Cen
• Secular dipole-dipole stability of magnetic binaries
• The evolution of magnetic fields in hot stars