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19982004
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astro-ph2004

BS Indi: An enigmatic object

E. W. Guenther, E. Covino, J. M Alcala +2

BS Ind is a young K0V star in the Tucana association. Photometric observations with the Hipparcos satellite show an eclipse-like light-curve with primary and secondary eclipse. The…

astro-ph2004

Late-type field stars in the RASS at high galactic latitude

F. -J. Zickgraf, J. Krautter, S. Frink +4

We present results of an investigation on a high-galactic latitude sample of late-type field stars selected from the ROSAT All-Sky Survey (RASS). The sample comprises about 200 G,…

astro-ph2000

Timescales of disk evolution and planet formation

W. Brandner, H. Zinnecker, J. M. Alcala +7

We present high-spatial resolution HST and adaptive optics observations, and high-sensitivity ISO (ISOCAM & ISOPHOT) observations of a sample of X-ray selected weak-line (WTTS) and…

astro-ph2000

The distance to the nearest star-forming clouds: MBM12 and MBM20

T. Hearty, M. Fernandez, J. M. Alcala +2

We present high-resolution spectra (R ~ 49,000) of stars that have parallax measurements from the Hipparcos satellite and are projected along the line of sight to the two nearest k…

astro-ph1999

The late-type stellar component in the ROSAT All-Sky Survey at high galactic latitude

F. -J. Zickgraf, J. M. Alcala, E. Covino +4

We investigated the properties of the late-type stellar component in the RASS at high-galactic latitude |b| based on an optically identified sample of ROSAT All-Sky Survey (RASS) X…

astro-ph1999

ROSAT PSPC observations of T Tauri stars in MBM12

T. Hearty, R. Neuhauser, B. Stelzer +4

We present the ROSAT PSPC pointed and ROSAT All-Sky Survey (RASS) observations and the results of our low and high spectral resolution optical follow-up observations of the T Tauri…