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astro-ph2000
Is the [CO] index an age indicator for star forming galaxies?
L. Origlia, E. Oliva
The classical [CO] index, i.e. the strength of the CO first overtone absorption bands starting at 2.29 micron, is sometimes used to constrain the maximum age of star formation even…
astro-ph1999
Coronal activity among open cluster stars
S. Randich
Focusing on ROSAT results for clusters in the Myr range, I first summarize our current understanding of the X-ray activity - rotation - age relationship. Then, the pr…
astro-ph1997
X-ray detections of weak Seyfert2's with BeppoSAX
M. Salvati, L. Bassani, R. Della Ceca +3
We report the detection in the X rays of two weak Seyfert2's (NGC3393 and NGC4941) with the Italian-Dutch satellite BeppoSAX. These are among the first sources observed in a sample…