Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=11.5cm,clip]{2648fig1.eps} \end{figure}$ Figure 1: Profiles of selected H₂ lines in the absorption system toward Q 0347-383. The letter "B'' marks lines which have a good profile but do not satisfy the selection criteria (see Sect. 4, and Fig. 3). The zero point of the radial velocity corresponds to the redshift $z_{\rm abs}=3.0249$ .
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In the text

$\begin{figure} \par\includegraphics[width=11cm,clip]{2648fig2.eps} \end{figure}$ Figure 2: Profiles of selected H₂ lines in the absorption system toward Q 0405-443. The letter "B'' marks lines which have a good profile but do not satisfy the selection criteria (see Sect. 4, and Fig. 3). The zero point of the radial velocity corresponds to the redshift $z_{\rm abs}=2.5947$ .
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In the text

$\begin{figure} \par\includegraphics[width=11.5cm,clip]{2648fig3.eps} \end{figure}$ Figure 3: Curves of growth for the observed absorption lines (bottom panels; $~ \lambda$ [Å], N[cm^-2]). The three top panels illustrate the procedure we use to fix the local continuum (solid bold line). The equivalent widths for the W4P3 and W1R1 lines ( first and second top panels) lie above the corresponding curves of growth. It means that the lines are probably blended. The equivalent widths for L7P3 line ( third top panel) lies under the curve of growth. It means that the real continuum (dash line) probably lies above the local one. In the analysis, we do not use these lines as well as other lines that are not on the curve of growth. (The error bars on the bottom panels show typical errors for the plotted points).
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In the text

$\begin{figure} \par\includegraphics[width=7.6cm,clip]{2648fig4.eps} \end{figure}$ Figure 4: The relative positions, $\zeta_{\rm i}=(z_{\rm i}-\bar{z})/(1+\bar{z})$ , of lines observed in the spectra of both quasars Q 0405-443 (filled circles) and Q 0347-383 (open circles) are plotted versus the sensitivity coefficient $K_{\rm i}$ . Here, $\bar{z}$ is the median redshift of all H₂ lines observed in the one corresponding spectrum. The lines are L3R3, L3R2, L5R2, L6R3, L6P2, W0Q2, L8P3, and L12R3 and $\lambda _{\rm lab}^{\rm a}$ are used. The 1 $\sigma$ error bars shown are observational (without laboratory errors). They are of the order of 3 mÅ (in the observer's frame). It can be seen that both sets of measurements are mutually consistent within observational errors. The fact that the two independent observational measurements agree well indicates that our data calibration and measurement procedure are reliable at the level required for the study.
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In the text

$\begin{figure} \par\includegraphics[width=13cm,clip]{2648fig5.eps} \end{figure}$ Figure 5: Regression analysis using rest wavelengths from energy levels (Sample A; left column) and from laser experiments (Sample P; right column) for both quasars ( top and middle rows) and the whole sample ( bottom row).
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In the text

$\begin{figure} \par\includegraphics[width=12cm,clip]{2648fig6.eps} \end{figure}$ Figure 6: Possible systematic effects. The left top panel illustrates the kinematic effect that could arise if absorption lines from different rotational levels J had different velocity positions in the spectrum (Jenkins & Peimbert 1997). It may mimic $\mu$ -variation if ranges of $K_{\rm i}$ for different J levels do not overlap. The observed situation is shown in the right top panel. The $K_{\rm i}$ ranges for J=1 and J=3 overlap enough and slopes are similar for each J levels within the statistical uncertainties. The second type of systematic error could be a consequence of any effect that could produce a shift increasing monotonously with wavelength: H₂ laboratory wavelengths, and/or Th-Ar calibration, air-vacuum wavelength conversion, atmospheric dispersion effects, instrumental profile variation with $\lambda$ etc. (Murphy et al. 2001). In that case, the regression lines for Lyman and Werner bands should be shifted from one to the other ( bottom left panel). It is apparent from the observation ( bottom right panel) that such an effect cannot be the dominant source of the correlation.
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In the text

$\begin{figure} \par\includegraphics[width=11.5cm,clip]{2648fig1.eps} \end{figure}$	Figure 1: Profiles of selected H₂ lines in the absorption system toward Q 0347-383. The letter "B'' marks lines which have a good profile but do not satisfy the selection criteria (see Sect. 4, and Fig. 3). The zero point of the radial velocity corresponds to the redshift $z_{\rm abs}=3.0249$ .
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$\begin{figure} \par\includegraphics[width=11cm,clip]{2648fig2.eps} \end{figure}$	Figure 2: Profiles of selected H₂ lines in the absorption system toward Q 0405-443. The letter "B'' marks lines which have a good profile but do not satisfy the selection criteria (see Sect. 4, and Fig. 3). The zero point of the radial velocity corresponds to the redshift $z_{\rm abs}=2.5947$ .
Open with DEXTER

$\begin{figure} \par\includegraphics[width=13cm,clip]{2648fig5.eps} \end{figure}$	Figure 5: Regression analysis using rest wavelengths from energy levels (Sample A; left column) and from laser experiments (Sample P; right column) for both quasars ( top and middle rows) and the whole sample ( bottom row).
Open with DEXTER