MG15 - Talk detail

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The Gross-Pitaevskii-Poisson (GPP) system of equations is appropriate to model the dynamics of Bose Condensate dark matter made of ultralight bosons in the non-linear regime of structure evolution. In this scenario the trap of the condensate is the gravitational potential generated by the mass density of the condensate itself. The GPP system of equations has stationary, spherically symmetric solutions called equilibrium configurations. Using numerical simulations we show these solutions are not only stable, but also late-time attractors. This means that despite the initial profile of a condensate dark matter structure -either spherically symmetric or not- after the turn-around of a cosmic fluctuation, the system relaxes through the gravitational cooling process and approaches a virialized state within a time scale , whereas the density profile tends toward one of the equilibrium configurations of the GPP system. Within the Bose condensate dark matter model, the clumpy density distributions of the condensate, in particular equilibrium configurations, are therefore assumed to be dark matter galactic halos. Then we construct the rotation curves of these equilibrium solutions and use them to fit observations using only the central density as a free parameter. We enrich the variety of rotation curves by numerically adding angular momentum to these solutions and show that the central density of the configuration together with its angular momentum suffice to parametrize a rotation curve. With this result we imply there is no need to use the self-interaction of bosons and the boson mass as free parameters to fit rotation curves as current analyses suggest. Going further in the analysis of the dynamics, we present the collision between two condensate halos and show there are solitonic and merger regimes. By carrying out sufficiently long simulations, we track the density of the long-term configuration resulting from a merger and construct a universal core-tail halo profile that can be contrasted with halo mass functions extracted from structure formation simulations.

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We present numerical simulations of jets modeled with Relativistic Radiation Hydrodynamics (RRH) triggered from inside a progenitor. We consider opacities consistent with interaction between the fluid and radiation of type free-free, bound-free, bound-bound and electron scattering. We explore various initial conditions, with different radiation energy densities of the beam in hydrodynamical and radiation pressure dominated scenarios, considering only highly-relativistic jets. In order to investigate the effect of the thermal radiation field on the evolution of these jets, we compare our results with purely hydrodynamical ones. Comparing among jets driven by RRH, we find that radiation pressure dominated jets propagate slightly faster than gas pressure dominated ones. We track the temperature of the fluid and radiation, showing they differ up to four orders of magnitude, indicating the two components are not in thermal equilibrium during the evolution of the jet. We construct the luminosity Light Curves (LCs) associated with the jets using the fluxes of the radiation field itself, which is fully coupled to the hydrodynamics equations during the evolution. We construct jets breaking out from the progenitor star with LCs of magnitude within the range of low-luminosity GRBs $10^{46}-10^{49}$ erg/s. Our results indicate that thermal radiation from jets emerging from a progenitor is a good candidates to explain the Long-Low Luminosity GRB events.

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