Projects:

1. Relativistic jets in GRBs:
   This are some gifs of my current work in relativistic simulations of GRBs in collaboration with Ewald Muller, Jose M. Marti and J.M. Ibanez. Initial models where calculated by Andrew MacFadyen and Stan E. Woosley (see astro-ph/9810274) using a two-dimensional (newtonian) hydrodynamics code (PROMETHEUS).
   1. Progenitors of Long GRBs (collapsar models)
   2. Progenitors of Short GRBs (collapsar models)
   3. Newest results: Movie showing a volume rendering of a ultrarelativistic jet generated after the merger of a pair of compact objects.
2. Relativistic Jets from AGNs and Microquasars: This are some gif files of my research in: "High-resolution 3D simulations of relativistic jets". The work is being done in collaboration with: J.M. Marti, J.M.Ibanez, J.L. Gomez and E. Mueller.

Relativistic Jets from AGNs and Microquasars

Abstract:

This are some gif files of my research in: "High-resolution 3D simulations of relativistic jets". The work is being done in collaboration with: J.M. Marti, J.M.Ibanez, J.L. Gomez and E. Mueller.

In this directory you can find some snapshots of the last states of evolution of several models which are perturbed using helical modes of a given frequency and amplitude. The common parameters of the simulations are:

• EOS: Gamma law: p = (gamma - 1)*rho*epsilon (gamma = 5/3)
• Mach Number: M = 6.0
• Beam to ambient density ratio: eta = 0.01
• Beam to ambient pressure ration: K = 1.0
• Unperturbed beam velocity: v = 0.99 (in units of the speed of light, c).

• vx = v * p * sin( 2 * pi * n * t / T )
• vy = v * p * cos( 2 * pi * n * t / T )
• vz = v * sqrt( 1 - p**2 )

Syntax of the names: naapbb_ccc_k.gif

• naa stands for the frequency (aa) of the perturbation.
• pbb is the strength of the perturbation (in units per cent).
• ccc is the snapshot time in units of Rb/c (Rb is the beam radius).
• k is 'a' or 'b'. For 'a' the plot shows 4 panels with the logarithms of the rest-mass density, pressure, and specific internal energy, and the Lorentz Factor. For 'b' the plot shows the Mach number and the backflow velocity (i.e., the value of v at those points for which vz < 0).

These are some video files of my research in: High-resolution 3D simulations of relativistic jets. The work is being done in collaboration with:J.Mª. Martí, J.Mª. Ibáñez, J.L. Gómez and E. Müller..
In this directory you can find some animations of the hole evolution of several models which are perturbed using helical modes of a given frequency and amplitude. The common parameters of the simulations are:

• EOS: Gamma law: P = (gamma - 1)*rho*epsilon (gamma = 5/3)
• Mach Number: M = 6.0
• Beam to ambient density ratio: eta = 0.01
• Beam to ambient pressure ration: K = 1.0
• Unperturbed beam velocity: v = 0.99 (in units of the speed of light, c) .

• vx = v * p * sin ( 2 * pi * n * t / T )
• vy = v * p * cos( 2 * pi * n * t / T )
• vz = v * sqrt( 1 - p**2 )

1. Three variables of the model n50p01 (gif-format) (63 Mb)
2. Pressure evolution: high quality, mpeg-format, 17 Mb. Low quality, mpeg-format, 2.1 Mb.
3. Density evolution: high quality, mpeg-format, 14 Mb. Low quality, mpeg-format, 1.8 Mb.
4. Lorentz factor evolution: high quality, mpeg-format, 13 Mb. Low quality, mpeg-format, 2.0 Mb.

1. Pressure evolution (high quality, mpeg-format) (3.4 Mb)
2. Lorentz factor evolution (high quality, mpeg-format) (2.8 Mb)

1. n50p01_153_a.gif
2. n50p01_153_b.gif
3. n15p05_170_a.gif
4. n15p05_170_b.gif

• Public Outreach
• Serious fun

Here you can find several movies and high-quality, colour coded versions of the figures of the paper entitled:
Does the plasma composition affect the long term evolution of relativistic jets?
Authors: L. Scheck (1), M. A. Aloy (1), J. M. Martí, (2), J. L. Gómez(3) and E. Müller(1).
(1) Max-Planck-Institut für Astrophysik.
(2) Departamento de Astronomía y Astrofísica -Universidad de Valencia-.
(3) Instituto de Astrofísica de Andalucía.

Abstract
We study the influence of the matter content of extragalactic jets on their morphology, dynamics and emission properties. For this purpose we consider jets of extremely different compositions including pure leptonic and baryonic plasmas. Our work is based on two-dimensional relativistic hydrodynamic simulations of the long-term evolution of powerful extragalactic jets propagating into a homogeneous environment. The equation of state used in the simulations accounts for an arbitrary mixture of electrons, protons and electron-positron pairs. Using the hydrodynamic models we have also computed synthetic radio maps and the thermal Bremsstrahlung X-ray emission from their cavities.
Although there is a difference of about three orders of magnitude in the temperatures of the cavities inflated by the simulated jets, we find that both the morphology and the dynamic behaviour are almost independent on the assumed composition of the jets. Their evolution proceeds in two distinct epochs. During the first one multidimensional effects are unimportant and the jets propagate ballistically. The second epoch starts when the first larger vortices are produced near the jet head causing the beam cross section to increase and the jet to decelerate. The evolution of the cocoon and cavity is in agreement with a simple theoretical model. The beam velocities are relativistic ($\Gamma \simeq 4$) at kiloparsec scales supporting the idea that the X-ray emission of several extragalactic jets may be due to relativistically boosted CMB photons. The radio emission of all models is dominated by the contribution of the hot spots. All models exhibit a depression in the X-rays surface brightness of the cavity interior in agreement with recent observations.

High quality figures
figure 2, figure 3 , figure 4, figure 10 , figure 11.

Movies
The dynamical evolution of the logarithm of the rest-mass density of the three models studied in the paper can be seen in the following mpeg files: Model BC, Model LC, Model LH.