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…
New Gamma Ray sources discovered by INTEGRAL
Combi, J. A.
One of the strategic objective of the INTEGRAL mission is a regular survey of the galactic plane complemented by a deep exposure of the Galactic Centre. This study is carrying out by the imaging capability of IBIS, which allows the detection of sources at the mCrab level with an angular resolution of 12 arcmin and a point souce location accuracy o…
Absolute magnitudes of galactic R Coronae Borealis Stars
Milone, L. A.; Merlo, D. C.
For a long time it was generally accepted that galactic R Coronae Borealis (RCrB) stars are rather bright objects: absolute visual magnitudes ranging from -4 up to -5. On the contrary, an analysis of a sample of 15 stars of this type belonging to the Large Magellanic Cloud recently showed, that some of them are considerably fainter: absolute magni…