Eva Verdugo

ESA ISO, Akari and Herschel

I am an ultraviolet (and optical) scientist. I joined 
the IUE Observatory on 1992 to start my PhD thesis with Antonio
Talavera and lately also with Ana Ines Gomez de Castro, on the
atmospheres and winds of A-type Supergiants. At that time, very
few works were devoted to these stars; mainly because of the
difficulty to model their atmospheres. These objects are at the 
boundary between hot and cool stars. They are located in a region
of the HR diagram where the evolution is very rapid and they are
very few in number. Even their evolutionary stage is poorly known;
they can be evolved directly from the main sequence or be placed
at the unknown region of "blue loops". These stars are supposed to
have radiation-driven winds but the predictions of radiative wind
models do not fit their UV and optical spectra. We showed that an
alternative force could be in competition with the radiation field;
this is a weak surface magnetic field. A magnetic field of just
25-50 G could produce dramatic changes in the line profiles
resembling the observations. I have been searching for such a
magnetic field for almost 10 years now, using the most advanced
spectropolarimetric techniques without a big success.

In the mean time we have found weak magnetic fields (~ 100 G) in
some other massive stars which have become another research topic
for me in collaboration with some colleagues from the University of
Amsterdam.

My last research interest is also related to magnetic fields but in
completely different objects: T-Tauri stars for which I collaborate
with Ana Ines Gomez de Castro in the study of accretion disks and
jets from UV spectroscopy.