Naslov
Magellanic Clouds' Binaries as Distance Indicators

Autori
Dominis, Dijana ; Butler, Keith ; Simon, Klaus ; Clausen, Jens Viggo ; Pritchard, John

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Astronomische Gesellschaft Abstract Series Vol. 18 / - : American Geophysical Union (AGU), 2001

Skup
Annual Scientific Meeting of the Astronomische Gesellschaft at the Joint European and National Meeting JENAM 2001

Mjesto i datum
München, Njemačka, 10.09.2001. - 15.09.2001

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Eclipsing binary systems; B-type stars; spectroscopy

Sažetak
Detached eclipsing binary systems of B-type stars in the Large and Small Magellanic Clouds have been observed in order to determine distances to these galaxies. We obtained high resolution spectra using the UVES spectrograph at the VLT, ESO. Analysis of the spectra with strongly overlapping spectral lines, which are heavily broadened by the Stark effect and rotation, is only possible by means of the Disentangling Method. This allows us to not only determine accurate spectroscopic orbit parameters, but also the individual component spectra. In combination with high accuracy photometry we determine precise absolute dimensions of the components. Subsequent fine analyses of the component spectra by means of line blanketed model atmospheres and non-LTE line formation calculations yield independent photospheric parameters: effective temperature, gravity, and element abundances. While the element abundances will provide further constraints on the metallicity of the Magellanic Clouds, the spectroscopic effective temperature in combination with the binary parameters enables us to determine distances with unprecedented accuracy.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA