In this PhD thesis I have concentrated on the pulsation and magnetic
properties of three different kinds of early B-type stars: Be,
Cephei and Slowly Pulsating B (SPB)
stars. I present in-depth studies of a few carefully chosen targets,
which are representative for the variety of phenomena associated with
these massive stars. In all studied stars new non-radial pulsation
modes are found. By studying the UV stellar wind variations I could
derive the rotational period of these stars very precisely, which
allowed me to search for the presence of a magnetic field. Magnetic
fields were indeed found in these stars, which I have modeled as
simple dipole fields with a typical strength of a few hundred Gauss,
inclined with the stellar rotation axis. With present-day
instrumentation this is about the weakest field that can be detected
in such stars. With no exception, abundance anomalies are found to be
associated with these magnetic stars, for which I carried out a
quantitative analysis.
Cephei and Slowly Pulsating B (SPB)
stars. I present in-depth studies of a few carefully chosen targets,
which are representative for the variety of phenomena associated with
these massive stars. In all studied stars new non-radial pulsation
modes are found. By studying the UV stellar wind variations I could
derive the rotational period of these stars very precisely, which
allowed me to search for the presence of a magnetic field. Magnetic
fields were indeed found in these stars, which I have modeled as
simple dipole fields with a typical strength of a few hundred Gauss,
inclined with the stellar rotation axis. With present-day
instrumentation this is about the weakest field that can be detected
in such stars. With no exception, abundance anomalies are found to be
associated with these magnetic stars, for which I carried out a
quantitative analysis.