Search results for "MHD simulation"
showing 3 items of 3 documents
First M87 Event Horizon Telescope Results. I. the Shadow of the Supermassive Black Hole
2019
When surrounded by a transparent emission region, black holes are expected to reveal a dark shadow caused by gravitational light bending and photon capture at the event horizon. To image and study this phenomenon, we have assembled the Event Horizon Telescope, a global very long baseline interferometry array observing at a wavelength of 1.3 mm. This allows us to reconstruct event-horizon-scale images of the supermassive black hole candidate in the center of the giant elliptical galaxy M87. We have resolved the central compact radio source as an asymmetric bright emission ring with a diameter of 42 ± 3 μas, which is circular and encompasses a central depression in brightness with a flux rati…
UV And X-Ray Emission from Impacts of Fragmented Accretion Streams on Classical T Tauri Stars
2016
According to the magnetoshperic accretion scenario, during their evo- lution, Classical T Tauri stars accrete material from their circumstellar disk. The accretion process is regulated by the stellar magnetic eld and produces hot and dense post-shocks on the stellar surface as a result of impacts of the downfalling material. The impact regions are expected to strongly radiate in UV and X-rays. Several lines of evidence support the magnetospheric accretion scenario, especially in optical and infrared bands. However several points still remain unclear as, for instance,where the complex-pro le UV lines originate, or whether and how UV and X-ray emission is produced in the same shock region. Th…
Magnetic fields of relativistic jets in active galactic nuclei
2011
The motivation of my work is to understand the role played by the magnetic field in the dynamics and emission of relativistic jets. In order to achieve this objective I have been carrying it out in two parallel ways. In the first of them I have performed numerical magnetohydrodynamic and emission (eRMHD) simulations of relativistic jets. The simulations have been performed in collaboration with the Relativistic Astrophysics Group in the University of Valencia, using a numerical code that solves the RMHD equations in conservative form and cylindrical coordinates with axial symmetry (see Leismann et al., 2005, for more details). I have focused the study on the role played by the magnetic fiel…