http://biblioteca.universia.net/html_bura/vernivel/params/nivel/21.html Mostrando recursos 1 - 20 de 391 es es http://biblioteca.universia.net/img/logotipo.jpg http://biblioteca.universia.net/ http://biblioteca.universia.net/html_bura/ficha/params/title/white-dwarf-mergers-and-the-origin-of-r-coronae-borealis/id/56682103.html We present a nucleosynthesis study of the merger of a 0.4 M⊙ helium white dwarf with a 0.8 M⊙ carbon-oxygen white dwarf, coupling the thermodynamic history of Smoothed Particle Hydrodynamics particles with a post-processing code. The resulting chemical abundance pattern, particularly for oxygen and fluorine, is in qualitative agreement with the observed abundances in R Coronae Borealis stars. http://biblioteca.universia.net/html_bura/ficha/params/title/white-dwarf-mergers-and-the-origin-of-r-coronae-borealis/id/56682103.html Lorén Aguilar, Pablo; Longland, Richard Leigh; José Pont, Jordi; García-Berro Montilla, Enrique; Althaus, Leandro G.; Isern-Fontanet, J. http://biblioteca.universia.net/html_bura/ficha/params/title/interaction-of-supernovae-remnants-from-the-circumstellar-medium-to-the/id/56682101.html The evolution of supernova remnants (SNRs) represents a useful and natural laboratory for gasdynamics studies. In this paper the results of several hydrodynamical simulations of the propagation and early phases of interaction of two SNRs embedded in a homogeneous interstellar environment are shown. In particular, the hydrodynamic evolution and collision of twin SNRs during their self-similar stage has been simulated using a two-dimensional Lagrangian hydrocode. In addition, the results of a d... http://biblioteca.universia.net/html_bura/ficha/params/title/interaction-of-supernovae-remnants-from-the-circumstellar-medium-to-the/id/56682101.html Velarde, P; García Senz, Domingo; Bravo Guil, Eduardo; Ogando, F; Relaño, A; Oliva, E http://biblioteca.universia.net/html_bura/ficha/params/title/production-of-intermediate-mass-and-heavy-nuclei/id/56682100.html Nucleosynthesis is the science related to all astrophysical processes which are responsible for the abundances of the elements and their isotopes in the universe. The astrophysical sites are the big bang and stellar objects. The working of nucleosynthesis processes is presented in a survey of events which act as abundance sources. For intermediate-mass and heavy elements, these are stellar evolution, type Ia and core collapse supernovae as well as hypernovae. We discuss successes and failures... http://biblioteca.universia.net/html_bura/ficha/params/title/production-of-intermediate-mass-and-heavy-nuclei/id/56682100.html Thielemann, F. K.; Frölich, Carla; Hirschi, R.; Liebendörfer, M.; Dillmann, I.; Mocelj, D.; Rauscher, t.; Martínez Pinedo, Gabriel; Langanke, K; Farouqi, K; Kratz, K.L.; Pfeiffer, B.; Panov, I.; Nadyozhin, D.K.; Blinnikov, S.; Bravo Guil, Eduardo; Hix, W.R.; Höflich, P.; Zinner, Ernst http://biblioteca.universia.net/html_bura/ficha/params/title/consequences-of-the-collision-between-the-gas-ejected-in-the/id/56679711.html http://biblioteca.universia.net/html_bura/ficha/params/title/consequences-of-the-collision-between-the-gas-ejected-in-the/id/56679711.html Serichol Augué, Núria; García Senz, Domingo; Bravo Guil, Eduardo http://biblioteca.universia.net/html_bura/ficha/params/title/unified-one-dimensional-simulations-of-gamma-ray-line-emission-from/id/56679705.html The light curves of Type Ia supernovae (SNe Ia) are powered by gamma rays emitted by the decay of radioactive elements such as 56Ni and its decay products. These gamma rays are downscattered, absorbed, and eventually reprocessed into the optical emission that makes up the bulk of all SN observations. Detection of the gamma rays that escape the expanding star provide the only direct means to study this power source for SN Ia light curves. Unfortunately, disagreements between calculations for t... http://biblioteca.universia.net/html_bura/ficha/params/title/unified-one-dimensional-simulations-of-gamma-ray-line-emission-from/id/56679705.html Milne, P A; Hungerford, A L; Fryer, C L; Evans, T M; Urbatsch, T J; Boggs, S E; Isern Vilaboy, Jordi; Bravo Guil, Eduardo; Hirschmann, A; Kumagai, S; Pinto, P A; The, L S http://biblioteca.universia.net/html_bura/ficha/params/title/bounds-on-the-possible-evolution-of-the-gravitational-constant-from/id/56679700.html Recent high-redshift type-Ia supernovae results can be used to set new bounds on a possible variation of the gravitational constant G. If the local value of G at the space-time location of distant supernovae is different, it would change both the kinetic energy release and the amount of 56Ni synthesized in the supernova outburst. Both effects are related to a change in the Chandrasekhar mass MCh∝G-3/2. In addition, the integrated variation of G with time would also affect the cosmic evolution... http://biblioteca.universia.net/html_bura/ficha/params/title/bounds-on-the-possible-evolution-of-the-gravitational-constant-from/id/56679700.html Gaztañaga, E; García-Berro Montilla, Enrique; Isern Vilaboy, Jordi; Bravo Guil, Eduardo; Domínguez, I http://biblioteca.universia.net/html_bura/ficha/params/title/sixe-payload-for-minisat-02/id/56679694.html A description of the X-ray instrument SIXE proposed for the MINISAT-02 mission is presented. The description includes the scientific goals and instrument performances. http://biblioteca.universia.net/html_bura/ficha/params/title/sixe-payload-for-minisat-02/id/56679694.html Gómez, J; Isern Vilaboy, Jordi; Bravo Guil, Eduardo; Giovannelli, F; Padula, C L http://biblioteca.universia.net/html_bura/ficha/params/title/particle-code-for-deflagrations-in-white-dwarfs-i-numerical-techniques/id/56677825.html In this paper we report some specific features of the numerical technique used to study the dynamic evolution of massive white dwarfs following the explosive ignition of nuclear fuel under degenerate conditions. We focus on three important points: (1) how to construct a stable initial model for white dwarfs with a central density ρc > 109 g cm-3 in the context of smoothed particle hydrodynamics (SPH); (2) the procedure devised in the numerical handling of combustion fronts and thermal discont... http://biblioteca.universia.net/html_bura/ficha/params/title/particle-code-for-deflagrations-in-white-dwarfs-i-numerical-techniques/id/56677825.html García Senz, Domingo; Bravo Guil, Eduardo; Serichol Augué, Núria http://biblioteca.universia.net/html_bura/ficha/params/title/constraining-deflagration-models-of-type-ia-supernovae-through-intermediate-mass/id/56677824.html The physical structure of a nuclear flame is a basic ingredient of the theory of Type Ia supernovae (SNe Ia). Assuming an exponential density reduction with several characteristic times, we have followed the evolution of a planar nuclear flame in an expanding background from an initial density of 6.6 × 107 g cm-3 down to 2 × 106 g cm-3. The total amount of synthesized intermediate-mass elements (IMEs), from silicon to calcium, was monitored during the calculation. We have used the computed ma... http://biblioteca.universia.net/html_bura/ficha/params/title/constraining-deflagration-models-of-type-ia-supernovae-through-intermediate-mass/id/56677824.html García Senz, Domingo; Bravo Guil, Eduardo; Cabezón Gómez, Rubén Martín; Woosley, S E http://biblioteca.universia.net/html_bura/ficha/params/title/neutrino-induced-nucleosynthesis-of-64-nuclei-the-vp-process/id/56677823.html We present a new nucleosynthesis process that we denote as the νp process, which occurs in supernovae (and possibly gamma-ray bursts) when strong neutrino fluxes create proton-rich ejecta. In this process, antineutrino absorptions in the proton-rich environment produce neutrons that are immediately captured by neutron-deficient nuclei. This allows for the nucleosynthesis of nuclei with mass numbers A>64, making this process a possible candidate to explain the origin of the solar abundances of... http://biblioteca.universia.net/html_bura/ficha/params/title/neutrino-induced-nucleosynthesis-of-64-nuclei-the-vp-process/id/56677823.html Fröhlich, C; Martínez, G; Liebendörfer, M; Thielemann, F -K; Bravo Guil, Eduardo; Hix, W R; Langanke, K; Zinner, N T http://biblioteca.universia.net/html_bura/ficha/params/title/composition-of-the-innermost-core-collapse-supernova-ejecta/id/56677822.html With currently known input physics and computer simulations in one dimension, a self-consistent treatment of core-collapse supernovae does not yet lead to successful explosions, while two-dimensional models show some promise. Thus, there are strong indications that the delayed neutrino mechanism works combined with a multidimensional convection treatment for unstable layers (possibly with the aid of rotation, magnetic fields and/or still existent uncertainties in neutrino opacities). On the o... http://biblioteca.universia.net/html_bura/ficha/params/title/composition-of-the-innermost-core-collapse-supernova-ejecta/id/56677822.html Fröhlich, C; Hauser, P; Liebendörfer, M; Martínez, G; Thielemann, F -K; Bravo Guil, Eduardo; Zinner, N T; Hix, W R; Langanke, K; Mezzacappa, A; Nomoto, K http://biblioteca.universia.net/html_bura/ficha/params/title/collision-of-detonation-waves-and-its-implications-in-the-nucleosynthesis/id/56677818.html http://biblioteca.universia.net/html_bura/ficha/params/title/collision-of-detonation-waves-and-its-implications-in-the-nucleosynthesis/id/56677818.html García Senz, Domingo; Bravo Guil, Eduardo http://biblioteca.universia.net/html_bura/ficha/params/title/exploring-the-physics-of-type-ia-supernovae-through-the-x/id/56675043.html We present the results of an ongoing project to use the X-ray observations of Type Ia Supernova Remnants to constrain the physical processes involved in Type Ia Supernova explosions. We use the Tycho Supernova Remnant (SN 1572) as a benchmark case, comparing its observed spectrum with models for the X-ray emission from the shocked ejecta generated from di erent kinds of Type Ia explosions. Both the integrated spectrum of Tycho and the spatial distribution of the Fe and Si emission in the remn... http://biblioteca.universia.net/html_bura/ficha/params/title/exploring-the-physics-of-type-ia-supernovae-through-the-x/id/56675043.html Badenes, C; Borkowski, K; Bravo Guil, Eduardo; Hughes, J P; Hwang, U http://biblioteca.universia.net/html_bura/ficha/params/title/sph-simulations-of-deflagrations-in-supernovae/id/56675042.html Some results of a set of tridimensional calculations concerning the explosion of a white dwarf by means of a smooth particle hydrodynamics (SPH) code are presented. The burning front advance is solved along with the hydrodynamics of the whole star, and a characterization of the front surface in terms of fractal concepts is done. Our main result indicates that the surface of the deflagration front sought at the largest scales of the Rayleigh-Taylor instability can be characterized as a fractal... http://biblioteca.universia.net/html_bura/ficha/params/title/sph-simulations-of-deflagrations-in-supernovae/id/56675042.html Bravo Guil, Eduardo; García Senz, Domingo http://biblioteca.universia.net/html_bura/ficha/params/title/pulsating-reverse-detonation-models-of-type-ia-supernovae-i-detonation/id/56675041.html http://biblioteca.universia.net/html_bura/ficha/params/title/pulsating-reverse-detonation-models-of-type-ia-supernovae-i-detonation/id/56675041.html Bravo Guil, Eduardo; García Senz, Domingo http://biblioteca.universia.net/html_bura/ficha/params/title/beyond-the-bubble-catastrophe-of-type-ia-supernovae-pulsating-reverse/id/56675040.html http://biblioteca.universia.net/html_bura/ficha/params/title/beyond-the-bubble-catastrophe-of-type-ia-supernovae-pulsating-reverse/id/56675040.html Bravo Guil, Eduardo; García Senz, Domingo http://biblioteca.universia.net/html_bura/ficha/params/title/sixe-an-x-ray-experiment-for-the-minisat-platform/id/56675039.html http://biblioteca.universia.net/html_bura/ficha/params/title/sixe-an-x-ray-experiment-for-the-minisat-platform/id/56675039.html Bravo Guil, Eduardo; García-Berro Montilla, Enrique; Gutierrez Cabello, Jorge Luis; José Pont, Jordi; García Senz, Domingo; Cabestany Moncusí, Joan; Madrenas Boadas, Jordi http://biblioteca.universia.net/html_bura/ficha/params/title/pulsating-reverse-detonation-models-of-type-ia-supernovae-ii-explosion/id/56675038.html http://biblioteca.universia.net/html_bura/ficha/params/title/pulsating-reverse-detonation-models-of-type-ia-supernovae-ii-explosion/id/56675038.html Bravo Guil, Eduardo; García Senz, Domingo; Cabezón Gómez, Rubén Martín; Domínguez, I http://biblioteca.universia.net/html_bura/ficha/params/title/on-the-internal-composition-of-white-dwarfs/id/56645089.html http://biblioteca.universia.net/html_bura/ficha/params/title/on-the-internal-composition-of-white-dwarfs/id/56645089.html Isern Vilaboy, Jordi; Bravo Guil, Eduardo; García-Berro Montilla, Enrique; Domínguez, I; Salaris, M http://biblioteca.universia.net/html_bura/ficha/params/title/nucleosynthesis-as-result-of-multiple-delayed-detonations-in-type-ia/id/56645088.html The explosion of a white dwarf of mass 1.36 M⊙ has been simulated in three dimensions with the aid of a SPH code. The explosion follows the delayed detonation paradigm. In this case the deflagration-detonation transition is induced by the large corrugation of the flame front resulting from Rayleigh-Taylor instability and turbulence. The nucleosynthetic yields have been calculated, showing that some neutronized isotopes such as 54Fe or 58Ni are not overproduced with respect to the solar system... http://biblioteca.universia.net/html_bura/ficha/params/title/nucleosynthesis-as-result-of-multiple-delayed-detonations-in-type-ia/id/56645088.html García Senz, Domingo; Bravo Guil, Eduardo