Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=6.8cm,clip]{pics/0546fig1.eps} \end{figure}$ Figure 1: The geometry visualized for two systems of reference, the jet frame and the laboratory (host galaxy) frame, for which all quantities are indexed with an asterisk. We consider a single cloud of thermal proton-electron plasma with density $n_{\rm p}$ , that is relativistically moving through the interstellar medium of the host galaxy with density $n_{\rm i}^\ast$ . An observer would see radiation from the plasma cloud that is emitted at an angle $\theta$ with respect to its direction of motion.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{pics/0546fig2.eps} \end{figure}$ Figure 2: The absorption coefficients $\alpha$ for the free-free process and the synchrotron process for the jet model of Pohl & Schlickeiser (2000) with standard parameters (see Table 1). We display the situation after one hour in the observer's frame, at which time the plasma temperature is $T\approx 3\times 10^4~$ K. Apparently the system is dominated by free-free absorption.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{pics/0546fig3.eps} \end{figure}$ Figure 3: The emission coefficients j for the free-free process and the synchrotron process after one hour observed time for standard parameters, as in Fig. 2. The free-free emission is only visible because of the Razin effect. For $n_{\rm p} = 5\times 10^8\ {\rm cm}^{-3}$ the plasma frequency corresponds to $E_\nu \approx 8 \times 10^{-7}~ {\rm eV}$ , so we cover the entire valid energy spectrum.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{pics/0546fig4.eps} \end{figure}$ Figure 4: Emitted photon spectra after one hour of observed time in the jet system for the standard parameters ( $\theta ^{\rm obs}\approx 0.1^\circ$ , see Table 1) and $T\approx 3\times 10^4~$ K. The thermal Bremsstrahlung dominates at low energies only because of the Razin-effect, which suppresses the synchrotron spectrum here.
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In the text

$\begin{figure} \par\includegraphics[width=17.4cm,clip]{pics/0546fig5.eps} \end{figure}$ Figure 5: Emitted photon spectra in the jet frame after one hour of observed time for different emission angles, based on an exact treatment of the geometry. For high $\theta ^{\rm obs}$ , the slow evolution of the synchrotron part of the spectrum has been reproduced.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{pics/0546fig6.eps} \end{figure}$ Figure 6: The approximated cooling function according to Eq. (43).
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{pics/0546fig7.eps} \end{figure}$ Figure 7: The temperature as a function of time for the standard parameters as well as $n_{\rm i}^\ast=0.8\;\hbox{cm}^{-3}$ , for which the temperature becomes larger than 10⁹ K, where our model is invalid.
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{pics/0546fig8.eps} \end{figure}$ Figure 8: The three qualitatively different temperature regions as a function of the particle densities and the standard parameters ( $T_0 = 10^4~{\rm K}$ ). The dotted lines are for $\Gamma _0 = 600$ .
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In the text

$\begin{figure} \par\includegraphics[width=8.4cm,clip]{pics/0546fig9.eps} \end{figure}$ Figure 9: Light curves for three different energies in the observer frame. Here we have adopted the periodic peak injection introduced in Eq. (59) with the parameters a/b=50, a period of $\tau = 1000~{\rm s}$ observed time and $c=100~{\rm s}$ , i.e. 10% of the period time. Significant variations occur exclusively in the optical thick regime; the redshift of the source has been set to z=0.5.
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In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{pics/0546fi10.eps} \end{figure}$ Figure A.1: Definitons used in the text to calculate the integral over the emitting surface. Top view.

In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{pics/0546fi11.eps} \end{figure}$ Figure A.2: Possible configurations of the integral over x as a function of the other parameters.

In the text

$\begin{figure} \par\includegraphics[width=8.1cm,clip]{pics/0546fi12.eps} \end{figure}$ Figure A.3: Detailed view of the geometry in the x-direction for small "impact parameters'' a.

In the text

$\begin{figure} \par\includegraphics[width=8.1cm,clip]{pics/0546fi13.eps}\end{figure}$ Figure A.4: Detailed view of the geometry in the x-direction for large "impact parameters'' a.

In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{pics/0546fig2.eps} \end{figure}$	Figure 2: The absorption coefficients $\alpha$ for the free-free process and the synchrotron process for the jet model of Pohl & Schlickeiser (2000) with standard parameters (see Table 1). We display the situation after one hour in the observer's frame, at which time the plasma temperature is $T\approx 3\times 10^4~$ K. Apparently the system is dominated by free-free absorption.
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$\begin{figure} \par\includegraphics[width=8cm,clip]{pics/0546fig4.eps} \end{figure}$	Figure 4: Emitted photon spectra after one hour of observed time in the jet system for the standard parameters ( $\theta ^{\rm obs}\approx 0.1^\circ$ , see Table 1) and $T\approx 3\times 10^4~$ K. The thermal Bremsstrahlung dominates at low energies only because of the Razin-effect, which suppresses the synchrotron spectrum here.
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$\begin{figure} \par\includegraphics[width=17.4cm,clip]{pics/0546fig5.eps} \end{figure}$	Figure 5: Emitted photon spectra in the jet frame after one hour of observed time for different emission angles, based on an exact treatment of the geometry. For high $\theta ^{\rm obs}$ , the slow evolution of the synchrotron part of the spectrum has been reproduced.
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$\begin{figure} \par\includegraphics[width=8.5cm,clip]{pics/0546fig6.eps} \end{figure}$	Figure 6: The approximated cooling function according to Eq. (43).
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$\begin{figure} \par\includegraphics[width=8.2cm,clip]{pics/0546fig7.eps} \end{figure}$	Figure 7: The temperature as a function of time for the standard parameters as well as $n_{\rm i}^\ast=0.8\;\hbox{cm}^{-3}$ , for which the temperature becomes larger than 10⁹ K, where our model is invalid.
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$\begin{figure} \par\includegraphics[width=8.2cm,clip]{pics/0546fig8.eps} \end{figure}$	Figure 8: The three qualitatively different temperature regions as a function of the particle densities and the standard parameters ( $T_0 = 10^4~{\rm K}$ ). The dotted lines are for $\Gamma _0 = 600$ .
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$\begin{figure} \par\includegraphics[width=8.4cm,clip]{pics/0546fig9.eps} \end{figure}$	Figure 9: Light curves for three different energies in the observer frame. Here we have adopted the periodic peak injection introduced in Eq. (59) with the parameters a/b=50, a period of $\tau = 1000~{\rm s}$ observed time and $c=100~{\rm s}$ , i.e. 10% of the period time. Significant variations occur exclusively in the optical thick regime; the redshift of the source has been set to z=0.5.
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