In: Contributions of the Astronomical Observatory Skalnaté Pleso, vol. 38, no. 2
J. Silvester - G.a. Wade - O. Kochukhov - J.d. Landstreet - S. Bagnulo
Detaily:
Rok, strany: 2008, 341 - 346
Kľúčové slová:
stars: chemically peculiar, techniques: polarimetric
URL originálneho zdroja: http://www.astro.sk/caosp/Eedition/Abstracts/2008/Vol_38/No_2/pp341-346_abstract.html
O článku:
Historically, the magnetic field geometries of the chemically peculiar Ap
stars were modelled in the context of a simple dipole field. However, with
the acquisition of increasingly sophisticated diagnostic data, it has become
clear that the large-scale field topologies exhibit important departures from
this simple model. Recently, new high-resolution circular and linear
polarisation spectroscopy has even hinted at the presence of strong,
small-scale field structures, which were completely unexpected based on
earlier modelling. This project investigates the detailed structure of these
strong fossil magnetic fields, in particular the large-scale field geometry,
as well as small scale magnetic structures, by mapping the magnetic and
chemical surface structure of a selected sample of Ap stars. These maps will
be used to investigate the relationship between the local field vector and
local surface chemistry, looking for the influence the field may have on the
various chemical transport mechanisms (i.e., diffusion, convection and mass
loss). This will lead to better constraints on the origin and evolution, as
well as refining the magnetic field model for Ap stars.
Mapping will be performed using high resolution and signal-to-noise ratio
time-series of spectra in both circular and linear polarisation obtained
using the new-generation ESPaDOnS (CFHT, Mauna Kea, Hawaii) and NARVAL
spectropolarimeters (Pic du Midi Observatory). With these data we will perform tomographic
inversion of Doppler-broadened Stokes IQUV Zeeman profiles of a
large variety
of spectral lines using the INVERS10 magnetic Doppler imaging code,
simultaneously recovering the detailed surface maps of the vector magnetic
field and chemical abundances.
Ako citovať:
ISO 690:
Silvester, J., Wade, G., Kochukhov, O., Landstreet, J., Bagnulo, S. 2008. Magnetic Doppler imaging of Ap stars. In Contributions of the Astronomical Observatory Skalnaté Pleso, vol. 38, no.2, pp. 341-346. 1335-1842.
APA:
Silvester, J., Wade, G., Kochukhov, O., Landstreet, J., Bagnulo, S. (2008). Magnetic Doppler imaging of Ap stars. Contributions of the Astronomical Observatory Skalnaté Pleso, 38(2), 341-346. 1335-1842.