Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=7cm,clip]{1434fig1.eps} \end{figure}$ Figure 1: Energy level diagram of O V. Only the n=2 levels are shown. The energy differences within the ³P triplets have been exaggerated for clarity. Solid lines: transitions with transition probabilities larger than 1 s^-1; the line thickness is proportional to the logarithm of the transition probability. Dashed lines: transitions with transition probabilities less than 1 s^-1.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig2.eps} \end{figure}$ Figure 2: Population of the 2s 2p ³P triplet with respect to the ground state in O V as a function of density and kT (in eV) as labeled. All three sublevels (J=0, J=1 and J=2) have been added.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig3.eps} \end{figure}$ Figure 3: Spectral energy distribution (thick line) used for our photoionisation calculations. The thin line shows the same spectrum absorbed by a Galactic foreground of cold gas with a hydrogen column density of $1.64\times 10^{24}$ m^-2 and $\sigma _v = 10$ km s^-1.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig4.eps} \end{figure}$ Figure 4: Temperature ( upper panel) and O V fraction ( lower panel) as a function of ionisation parameter $\xi$ . The maximum O V concentration of 40% occurs for $\log \xi = -0.05$ , at a temperature kT=1.9 eV (to be compared with 47% at kT=21.0 eV under CIE conditions).
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig5.eps} \end{figure}$ Figure 5: Population of the 2s 2p ³P triplet with respect to the ground state in O V as a function of density and kT (in eV) as labeled for a photoionised plasma. All three sublevels (J=0, J=1 and J=2) have been added.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig6.eps} \end{figure}$ Figure 6: Population of the 2s 2p ³P triplet with respect to the ground state in O V as a function of density and kT (in eV) in a photoionised plasma. Solid curves are for kT=2 eV, dash-dotted curves for kT=4 eV. Labels indicate $\log N$ with N the column density of O V in m^-2. All three sublevels (J=0, J=1 and J=2) have been added.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig7.eps} \end{figure}$ Figure 7: Chandra LETGS spectrum of Mrk 279 near the oxygen absorption lines. The observed spectrum has been divided by the best fit simple continuum model described in the text (dashed line). The additional broad emission feature is indicated by the curved line. The wavelength scale is for the restframe of Mrk 279 (at z=0.0306). In the line identifications, we have taken into account a small outflow (blueshift) of 300 km s^-1 with respect to this restframe; this outflow has been measured using simultaneous high-resolution UV spectra. A few Galactic absorption lines are labeled with "Gal''.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig8.eps} \end{figure}$ Figure 8: Curve of growth for the most important K-shell absorption lines of O V, for a Gaussian velocity broadening $\sigma _v$ of 50 km s^-1.
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In the text

$\begin{figure} \par\includegraphics[width=7cm,clip]{1434fig1.eps} \end{figure}$	Figure 1: Energy level diagram of O V. Only the n=2 levels are shown. The energy differences within the ³P triplets have been exaggerated for clarity. Solid lines: transitions with transition probabilities larger than 1 s^-1; the line thickness is proportional to the logarithm of the transition probability. Dashed lines: transitions with transition probabilities less than 1 s^-1.
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$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig2.eps} \end{figure}$	Figure 2: Population of the 2s 2p ³P triplet with respect to the ground state in O V as a function of density and kT (in eV) as labeled. All three sublevels (J=0, J=1 and J=2) have been added.
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$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig3.eps} \end{figure}$	Figure 3: Spectral energy distribution (thick line) used for our photoionisation calculations. The thin line shows the same spectrum absorbed by a Galactic foreground of cold gas with a hydrogen column density of $1.64\times 10^{24}$ m^-2 and $\sigma _v = 10$ km s^-1.
Open with DEXTER

$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig4.eps} \end{figure}$	Figure 4: Temperature ( upper panel) and O V fraction ( lower panel) as a function of ionisation parameter $\xi$ . The maximum O V concentration of 40% occurs for $\log \xi = -0.05$ , at a temperature kT=1.9 eV (to be compared with 47% at kT=21.0 eV under CIE conditions).
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$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig5.eps} \end{figure}$	Figure 5: Population of the 2s 2p ³P triplet with respect to the ground state in O V as a function of density and kT (in eV) as labeled for a photoionised plasma. All three sublevels (J=0, J=1 and J=2) have been added.
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$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig6.eps} \end{figure}$	Figure 6: Population of the 2s 2p ³P triplet with respect to the ground state in O V as a function of density and kT (in eV) in a photoionised plasma. Solid curves are for kT=2 eV, dash-dotted curves for kT=4 eV. Labels indicate $\log N$ with N the column density of O V in m^-2. All three sublevels (J=0, J=1 and J=2) have been added.
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$\begin{figure} \par\includegraphics[angle=-90,width=8.8cm,clip]{1434fig8.eps} \end{figure}$	Figure 8: Curve of growth for the most important K-shell absorption lines of O V, for a Gaussian velocity broadening $\sigma _v$ of 50 km s^-1.
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