Jets and outflows in Radio Galaxies: implications for AGN feedback

One of the main debated astrophysical problems is the role of the AGN feedback in galaxy formation. It is known that massive black holes have a profound effect on the formation and evolution of galaxies, but how black holes and galaxies communicate is still an unsolved problem. For Radio Galaxies, feedback studies have mainly focused on jet/cavity systems in the most massive and X-ray luminous galaxy clusters. The recent high-resolution detection of warm absorbers in some Broad Line Radio Galaxies allow us to investigate the interplay between the nuclear engine and the surrounding medium from a different perspective. We report on the detection of warm absorbers in two Broad Line Radio Galaxies, 3C 382 and 3C 390.3, and discuss the physical and energetic properties of the absorbing gas. Finally, we attempt a comparison between radio-loud and radio-quiet outflows.Comment: To be published in the proceedings of High Energy Phenomena in Relativistic Outflows III (HEPRO III, IJMPCS). 4 pages, 2 figure

3C 33: another case of photoionized soft X-ray emission in radio galaxies

All the observations available in the Chandra and XMM-Newton archives have been used to investigate the X-ray spectral properties of 3C 33. In this paper is presented a complete X-ray analysis of the nuclear emission of this narrow line radio galaxy. The broad band spectrum of 3C 33 is complex. The hard part resembles that of Seyfert 2 galaxies, with a heavily obscured nuclear continuum (N_H~10^23 cm^-2) and a prominent Fe Kalpha line. This represents the nuclear radiation directly observed in transmission through a cold circumnuclear gas. On the other hand an unabsorbed continuum plus emission lines seem to fit well the soft part of the spectrum (0.5-2 keV) suggesting that the jet does not significantly contribute to the X-ray emission. We discuss the possible collisional or photoionized origin of the gas that emits the soft X-ray lines. Our results, strengthened by optical spectroscopy favor the photoionization scenario.Comment: 7 pages, 5 figures, accepted for publication in A&

Simbol-X Background Minimization: Mirror Spacecraft Passive Shielding Trade-Off Study

The present work shows a quantitative trade-off analysis of the Simbol-X Mirror Spacecraft (MSC) passive shielding, in the phase space of the various parameters: mass budget, dimension, geometry, and composition. A simplified physical (and geometrical) model of the sky screen, implemented by means of a GEANT4 simulation, has been developed to perform a performance-driven mass optimization and evaluate the residual background level on Simbol-X focal plane.Comment: 3 pages, 6 figures, to appear in the proceedings of the second Simbol-X International Symposium "Simbol-X - Focusing on the Hard X-ray Universe", AIP Conf. Proc. Series, P. Ferrando and J. Rodriguez ed

Towards an optical potential for rare-earths through coupled channels

The coupled-channel theory is a natural way of treating nonelastic channels, in particular those arising from collective excitations, defined by nuclear deformations. Proper treatment of such excitations is often essential to the accurate description of reaction experimental data. Previous works have applied different models to specific nuclei with the purpose of determining angular-integrated cross sections. In this work, we present an extensive study of the effects of collective couplings and nuclear deformations on integrated cross sections as well as on angular distributions in a consistent manner for neutron-induced reactions on nuclei in the rare-earth region. This specific subset of the nuclide chart was chosen precisely because of a clear static deformation pattern. We analyze the convergence of the coupled-channel calculations regarding the number of states being explicitly coupled. Inspired by the work done by Dietrich \emph{et al.}, a model for deforming the spherical Koning-Delaroche optical potential as function of quadrupole and hexadecupole deformations is also proposed. We demonstrate that the obtained results of calculations for total, elastic and inelastic cross sections, as well as elastic and inelastic angular distributions correspond to a remarkably good agreement with experimental data for scattering energies above around a few MeV.Comment: 7 pages, 6 figures. Submitted to the proceedings of the XXXVI Reuni\~ao de Trabalho de F\'{\i}sica Nuclear no Brasil (XXXVI Brazilian Workshop on Nuclear Physics), held in Maresias, S\~ao Paulo, Brazil in September 2013, which should be published on AIP Conference Proceeding Series. arXiv admin note: substantial text overlap with arXiv:1311.1115, arXiv:1311.042

Molecular Lines in Bok Globules and Around Herbig Ae/be Stars

This paper is intended as part of a more extensive molecular line survey in star forming regions along the evolutionary track of a collapsing cloud toward a young stellar object. We have studied a sample of seven small dark clouds (Bok globules) and eight Herbig Ae/Be stars in the J=1->0 transition of HCO$^{+}$, H$^{13}$CO$^{+}$, HCN and H$^{13}$CN. The choice of these molecules is determined by the simple chemistry and the predicted high abundance of the reactants leading to their formation. The isotopically substituted species (isotopomers), H$^{13}$CO$^{+}$ and H$^{13}$CN, were observed in order to determine, whenever possible, the optical thickness of the main species. The most abundant isotopomers were found in almost all the sources (detection rate 70-90\%). Those sources which exhibited the strongest signals were also searched for the $^{13}$C isotopomers. H$^{13}$CO$^{+}$ was found in one dark cloud and around three Herbig Ae/Be stars, while H$^{13}$CN around only one star. The column densities for each species and the physical conditions of the objects were derived whenever the observational data allowed it.Comment: 16 pages plus 6 figures available in hardcopy from [email protected] LaTEX ver. 2.09, BAP 11-1993-036-DD

XMM-Newton observations of ULIRGs I: A Compton-thick AGN in IRAS19254-7245

We present the XMM-Newton observation of the merging system IRAS 19254-7245, also known as The Superantennae, whose southern nucleus is classified as a Seyfert 2 galaxy. The XMM-Newton data have allowed us to perform a detailed X-ray imaging and spectral analysis of this system. We clearly detect, for the first time in this system, a strong EW ~ 1.4 keV Fe emission line at 6.49+/-0.1 keV (rest-frame). The X-ray spectrum requires a soft thermal component (kT~0.9 keV; L(0.5-2) ~ 4E41 cgs), likely associated with the starburst, and a hard power-law continuum above 2 keV (observed L(2-10) ~ 4E42 cgs). We confirm the flatness of this latter component, already noted in previous ASCA data. This flatness, together with the detection of the strong Fe-Kalpha line and other broad band indicators, suggest the presence of a Compton-thick AGN with intrinsic luminosity > 1E44 cgs. We show that a Compton-thick model can perfectly reproduce the X-ray spectral properties of this object.Comment: 6 pages, 4 figures, Latex manuscript, Accepted for publication in Astronomy and Astrophysic