The galactic unclassified B[e] star HD 50138. II. Interferometric constraints on the close circumstellar environment

Дата и время публикации : 2011-01-25T22:06:36Z

Авторы публикации и институты :
Marcelo Borges Fernandes (Observatorio Nacional, Brazil, Fizeau, France)
Anthony Meilland (MPIFR, Germany)
Philippe Bendjoya (Fizeau, France)
Armando Domiciano de Souza (Fizeau, France)
Gilles Niccolini (Fizeau, France)
Olivier Chesneau (Fizeau, France)
Florentin Millour (MPIFR, Germany)
Alain Spang (Fizeau, France)
Philippe Stee (Fizeau, France)
Michaela Kraus (Astronomicky ustav Ondrejov, Czech Republic)

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: Paper accepted for publication in Astronomy and Astrophysics (9 pages, 5 figures, 2011 in press)
Первичная категория: astro-ph.SR

Все категории : astro-ph.SR

Краткий обзор статьи: HD 50138 is a southern star that presents the B[e] phenomenon, but its evolutionary stage is still not well known. This object presents spectral variability, which can be explained by outbursts or shell phases and spectropolarimetric observations have shown the presence of a non-spherically symmetric circumstellar environment that is responsible for the B[e] phenomenon. Based on recent optical long baseline interferometric observations from the VLTI/MIDI and VLTI/AMBER, and also from the Keck segment-tilting experiment, we study the structure of the circumstellar environment of HD 50138, through a geometrical analytical modeling, also using the recent LITpro software and considering a large space of parameters. We resolve and describe its circumstellar geometry for the first time in detail. The presence of a dusty circumstellar disk with an orientation onto the sky-plane of 71+-7 degrees, which is perpendicular to the polarimetric measurements from the literature, was derived. We also derived that HD 50138 is seen under an intermediate angle related to the line of sight, 56+-4 degrees. In addition, the structure of the disk and the flux contributions of the gas and dust components is discussed.

Category: Physics