ICATE   21876
INSTITUTO DE CIENCIAS ASTRONOMICAS, DE LA TIERRA Y DEL ESPACIO
Unidad Ejecutora - UE
artículos
Título:
Early Results from the Galactic O-Star Spectroscopic Survey: C III Emission Lines in Of Spectra
Autor/es:
WALBORN, N.R.; SOTA, A.; MAÍZ APELLÁNIZ, J.; ALFARO, E.J.; MORRELL, N.I.; BARBÁ, R. H.; ARIAS, J.I.; GAMEN, R.C.
Revista:
ASTROPHYSICAL JOURNAL
Editorial:
IOP PUBLISHING LTD
Referencias:
Año: 2010 vol. 711 p. 143 - 147
ISSN:
0004-637X
Resumen:
On the basis of an extensive new spectroscopic survey of Galactic O
stars, we introduce the Ofc category, which consists of normal spectra
with C III λλ4647-4650-4652 emission lines of comparable
intensity to those of the Of defining lines N III
λλ4634-4640-4642. The former feature is strongly peaked to
spectral type O5, at all luminosity classes, but preferentially in some
associations or clusters and not others. The relationships of this
phenomenon to the selective C III λ5696 emission throughout the
normal Of domain, and to the peculiar, variable Of?p category, for which
strong C III λλ4647-4650-4652 emission is a defining
characteristic, are discussed. Magnetic fields have recently been
detected on two members of the latter category. We also present two new
extreme Of?p stars, NGC 1624-2 and CPD -28° 2561, bringing the
number known in the Galaxy to five. Modeling of the behavior of these
spectral features can be expected to better define the physical
parameters of both normal and peculiar objects, as well as the atomic
physics involved.