Search Publications

Spectral Energy Distribution in the symbiotic system BI Cru

Cidale, L. S.; Brandi, E.; Muratore, M. F. +1 more

BI Crucis is a symbiotic star classed as a D-type (dusty). It comprises a Mira variable; a hot compact object and a large bipolar nebula. We model the continuum spectral energy distribution of this star in a wide range of wavelengths. We derive its fundamental parameters using a theoretical model developed by zorec-1998 (Proceedings of the Paris w…

Distribuciones Espectrales de Energía de las compañeras visibles en sistemas binarios que albergan agujeros negros de masas estelares

Cúneo, V. A.; Gómez, M. N.

Stellar mass black holes are mainly detected in binary systems; where the compact object accretes material from its visible compa-nion. With the objective of characterizing visible companions; we analyse the Spectral Energy Distributions (SEDs) of a sample of these objects; selected from a galactic stellar black holes catalogue built by the author…

Detección de la estrella simbiótica Hen 2-87 en rayos X con XMM-Newton

Luna, G. J. M.; Nuñnez, N. E.

Symbiotic stars are interacting binary systems, where accretion, most of the times, occurs onto a white dwarf. Until recently only a couple of dozens of symbiotics were known to be X-ray emitters, with most of the emission having energies of less than about 2.00 keV. In the last decade, with the launch of modern X-ray satellites such as XMM-Newton…

Is there a Central Compact Object within G290.1--0.8?

Bocchino, F.; Combi, J. A.; García, F. +3 more

We study the central region of the supernova remnant (SNR) G290.1--0.8 in order to search for a possible compact stellar remnant associated to it. Our analysis of XMM-Newton and Chandra archival observations reveals three point-like sources. Two of them are hard X-ray sources, possibly Active Galactic Nuclei. The third one, located very close to t…

The cosmic history of black hole growth

Treister, E.

Significant progress has been made in the last few years in our understand- ing of how and when supermassive black holes form and grow. Here, I review our current knowledge of the cosmic evolution of the population of Active Galactic Nuclei (AGN), which hosts most of the supermassive black hole growth. Thanks to deep multiwavelength surveys it has…

Estrellas Be: diagnóstico del medio circunestelar mediante líneas de H del IR cercano

Granada, A.; Arias, M. L.; Cidale, L. S. +1 more

We describe the behavior of the IR emission lines that appear in the K and L band spectra of Be stars and discuss the physical properties of the circum- stellar envelopes based on the classification scheme proposed by Mennick- ent et al. (2009). We found that for stars of Group I, Pfund and Humphreys lines form in an optical thick region, while fo…

Multi-cycle chromospheric activity in II Peg and V711 Tau

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

In this work, we studied the Mount Wilson indexes we obtained indirectly from both IUE high and low-resolution spectra of the RS CVn-type systems II Peg (K2IV) and V711 Tau (K1IV+G5V). For both systems, we found a long-term chromospheric activity cycle related to the mean level of activity of the primary star and a shorter cycle associated to the …

Possible origin of the Saturn satellite, Phoebe

Brunini, A.; Di Sisto, R. P.

The orbit of the outermost Saturn's irregular moon, Phoebe, suggests that it was captured by Saturn rather than formed in situ. The Cassini-Huygens mission results allowed to find that Phoebe's composition is similar to that derived for the outer solar system bodies and very different from the composition of the Saturn regular satellites. In this …

Habitability around M stars: the action of flares

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

We analyzed the UV habitable zones (UV-HZ), defined in Buccino et al. (2006), around planetary dM stars observed by IUE: HIP 74995, HIP 109388, HIP 113020 and around two dMe stars: Ad Leo and EV Lac. We found that moderate flares could be an energy source in the biogenesis processes.

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Positional correlation between NVSS and XMM-Newton sources

Combi, J. A.; Romero, G. E.; Martí, J. +5 more

We present the preliminary results of a cross-identification between radio, infrared and X-ray data, in order to study X-ray populations at low and high galactic latitudes. For this purpose, we developed an improved search strategy based on very restrictive selection criteria being applied to the sources, using the NVSS, 2MASS and XMM catalogs. Us…