Search Publications

UV radiation as biologic limit in the origin and development of life in extrasolar planets

Buccino, A. P.; Mauas, P. J. D.; Lemarchand, G. A.

In this work, we displayed a new biological criterion that restricts the traditional habitable zone. We set the internal boundary of this new UV habitable zone from the maximum radiation that tolerates the DNA and its external boundary from the levels of UV radiation needed in the biogenesis processes. We also analyzed the evolution of the habitab…

Long-term variations of the Be star 88 Her

Granada, A.; Cidale, S. L.

Since its discovery as a variable star, 88 Her has undergone three photometric long-term variation cycles with transitions between Be-Shell and normal B phases. From the spectroscopic analysis of fifteen high resolution spectra obtained by the IUE satellite, we found that the radial velocities of Fe II lines follow the orbital cycle of the binary …

Young and Explosive BAL QSOs (at low and high redshifts)

Zheng, W.; Terlevich, R.; Mediavilla, E. +7 more

study of outflow (OF) and BAL systems in QSOs is presented. This study is based mainly on 1D and 3D spectroscopy (obtained at La Palma/WHT, HST, IUE, ESO/NTT, KPNO, APO and CASLEO observatories) plus HST images. In particular, for the nearest BAL QSO Mrk 231, we found clear evidence that the extreme nuclear OF process has at least 3 main and compo…