5 research outputs found

    Relativistic spine jets from Schwarzschild black holes: "Application to AGN radioloud sources"

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    The two types of Fanaroff-Riley radio loud galaxies, FRI and FRII, exhibit strong jets but with different properties. These differences may be associated to the central engine and/or the external medium. Aims: The AGN classification FRI and FRII can be linked to the rate of electromagnetic Poynting flux extraction from the inner corona of the central engine by the jet. The collimation results from the distribution of the total electromagnetic energy across the jet, as compared to the corresponding distribution of the thermal and gravitational energies. We use exact solutions of the fully relativistic magnetohydrodynamical (GRMHD) equations obtained by a nonlinear separation of the variables to study outflows from a Schwarzschild black hole corona. A strong correlation is found between the jet features and the energetic distribution of the plasma of the inner corona which may be related to the efficiency of the magnetic rotator. It is shown that observations of FRI and FRII jets may be partially constrained by our model for spine jets. The deceleration observed in FRI jets may be associated with a low magnetic efficiency of the central magnetic rotator and an important thermal confinement by the hot surrounding medium. Conversely, the strongly collimated and accelerated FRII outflows may be self collimated by their own magnetic field because of the high efficiency of the central magnetic rotator.Comment: Accepted for publication in the A&

    Dynamic Boundaries of Action Based Learning: the Longitudinal Impact (Invited Paper)

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    How do communities and group-based efforts create, learn and evolve? This paper argues that communities are dynamic, continuously creating connections through cyclical learning processes, regardless of how tight or loosely formulated group based efforts are (Hall et al. 2012).<br><br> Learning cycles or epicycles processes are relevant for action-based investigation within organizational and social structures. The question of behaviors across boundaries or groups maybe influenced by their positioning within a larger adaptive system, including the type of focus, determined goals and the type of connections that have been developed over time (longitudinally).<br><br> These types of community or group efforts can be described as autopoietic systems, which operate within larger adaptive societal webs (Nousala 2014). The learning methodologies involved in investigating these types of dynamic phenomena need themselves to be dynamic. These methods can be viewed through longitudinal cycles, (which are essentially feedback loops that include extensive reflective time lines, integration before repetition) exposing these epicycles at work. The continuous recording of various processes through epicycles (which are the basis for learning cycles) provide a means to "qualitatively measuring" change, which would normally go unseen (Hall et. al 2012; Hall et al. 2005; Nousala and Hall 2008; Wenger and Synder 2000; Garduno et al. 2015)
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