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5 The spectroscopic database

The plots of Fig. 6 show the kinematic and line index profiles of the 35 Coma galaxies. The line of sight mean velocity v(r), line of sight velocity dispersion $\sigma (r)$, third (H3(r)) and fourth (H4(r)) order coefficient of the Gauss-Hermite decomposition of the line of sight velocity distributions are given, as well as the profiles of the line indices Mgb, $\langle {\rm Fe}\rangle$, [MgFe] and H$\beta $ as a function of the radial distance r. All profiles are folded with respect to the galaxy center (v and H3are folded antisymetrically). The radial profiles of the Mg2 index are only shown for data from run 3 and 6 (CA). No reasonable Mg2 profiles could be derived from the McDonald (run 2 and 5) and MDM (run 1 and 4) data since these spectra were strongly distorted by the varying focus of the spectrograph and no satisfactory correction could be applied. For the 11 galaxies observed at MDM the additionally derived NaD line index profiles are also show in Fig. 6. The shown H$\beta $ indices are not corrected for emission as suggested by G93 (see Sect. 4). The numerical values of these radial profiles are also listed in Tables 13 to 82 in Appendix B.

Different radial binnings for kinematic parameters and line indices occur for two reasons: On the one hand we used different wavelength range for the kinematic and the absorption index analysis. Hence a variation in the radial dependent S/N and consequently a different radial binning could occur. Additionally, for some galaxies the radial profile was focus corrected before deriving line indices. This also influences the radial S/N and hence the radial binning for the line index profiles.

For all 27 galaxies of the inner sample Jørgensen (1999, J99) lists aperture corrected, central $\sigma $ and Mg2[*] values from her own observations and the literature inside a standard aperture of diameter of $2 r_{\rm A} = 3.4''$. For 26 of this galaxies she also gives equivalent central H$\beta $ indices as well as equivalent central Mgb and <Fe> indices for 20 of them. Following Jørgensen et al. (1995b, JFK95b), we converted the aperture radius $r_{\rm A}$ in the "slit-equivalent'' radius $r_{\rm L}$ using the formula $r_{\rm L}=(\frac{r_{\rm A}}{1.025})^2\frac{\pi}{2b}$, where b is the slit width. With the given slit width in Table 3 $r_{\rm L}$is 1.2'', 1.7'' and 2.5'' for the CA, McD and MDM setup, respectively. Overplotted in Fig. 6 we show these aperture corrected mean values from J99 at the "slit-equivalent'' radii $r_{\rm L}$. No central values are available for the 8 galaxies of the outer sample. In Sect. 6 we will discuss the comparison of our data with those available in literature in details.

Comments on the radial profiles of some galaxies are given in the following. Examples of the used classes of the H$\beta $ emission strength are given in Fig. 5.


  \begin{figure}
\begin{tabular}{cc}
\psfig{figure=1702_f13.eps,width=7.2cm} &
\ps...
...,width=7.2cm} &
\psfig{figure=1702_f16.eps,width=7.2cm}\end{tabular}\end{figure} Figure 6: a) Radial profiles of the kinematical parameters along the major axis (folded). From bottom to top: line of sight mean velocity v(r), line of sight velocity dispersion $\sigma (r)$, third (H3(r)) and fourth (H4(r)) order coefficient of the Gauss-Hermite decomposition of the line of sight velocity distributions. b) Radial profiles of the line indices (from bottom to top) H$\beta $, [MgFe], $\langle$Fe$\rangle$ and Mgb. For a few galaxies either the Mg2 or the NaD index profile is also shown. The symbol $\dag $indicates the index profiles where a focus correction has been applied. Because of this correction the profiles appear smoother and the error bars are sometimes larger than the internal scatter of the data. Filled circles and crosses refer to the two sides of the galaxy. Open triangles (when present) show aperture corrected values from J99 inside the standard circular aperture having a diameter of 3.4''. Following JFK95b, we converted this aperture radius $r_{\rm A}$ in the "slit-equivalent'' radius $r_{\rm L}$ (see text), which is 1.2'', 1.7'' and 2.5'' for the CA, McD, and MDM setups, respectively. The vertical dashed line (when present) shows the position of $a_{\rm e} = r_{\rm e}/\sqrt {1-\epsilon _{\rm re}}$ indicating the half light radius projected to the observed major axis. The long-dashed horizontal line shows r=0. Name, type, $r_{\rm e}$and position angle of the galaxy are given at the top (left). The galaxy number indicated in Tables 1 and 3 are also shown at the top (right)


  \begin{figure}\begin{tabular}{cc}
\psfig{figure=1702_f17.eps,width=7.2cm} &
\psf...
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\psfig{figure=1702_f22.eps,width=7.2cm}\end{tabular}\end{figure} Figure 6: continued


  \begin{figure}\begin{tabular}{cc}
\psfig{figure=1702_f23.eps,width=7.2cm} &
\psf...
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\psfig{figure=1702_f28.eps,width=7.2cm}\end{tabular}\end{figure} Figure 6: continued


  \begin{figure}\begin{tabular}{cc}
\psfig{figure=1702_f29.eps,width=7.2cm} &
\psf...
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\psfig{figure=1702_f34.eps,width=7.2cm}\end{tabular}\end{figure} Figure 6: continued


  \begin{figure}\begin{tabular}{cc}
\psfig{figure=1702_f35.eps,width=7.2cm} &
\psf...
...,width=7.2cm} &
\psfig{figure=1702_f40.eps,width=7.2cm}\end{tabular}\end{figure} Figure 6: continued


  \begin{figure}\begin{tabular}{cc}
\psfig{figure=1702_f41.eps,width=7.2cm} &
\psf...
...,width=7.2cm} &
\psfig{figure=1702_f46.eps,width=7.2cm}\end{tabular}\end{figure} Figure 6: continued



  \begin{figure}\psfig{figure=1702_f47.eps,width=7.2cm}\end{figure} Figure 6: continued

Comments on single galaxies:

(1) cD Galaxy GMP 3329 (NGC 4874): Weak, asymmetric NI emission contaminates the Mgb index at r $\approx$ 5'' - 8''. Weak H$\beta $ emission contaminates the H$\beta $ absorption index at r $\approx$ 8'' - 12''. The mean H$\beta $ index from J99 is significantly lower compared to our profile.
(2) D Galaxy GMP 2921 (NGC 4889) Weak H$\beta $ emission contaminates the H$\beta $ absorption index in the center and at r $\approx$8''. The Mgb peak at r $\approx$ 4'' is real as well as the differences of the $\langle$Fe$\rangle$ index at different sides of the galaxy. There is no evidence for further emission or systematic errors in the continuum shape.
(3) cD Galaxy GMP 4928 (NGC 4839) (SW): A foreground object existing between +16''and +22'' has been excluded from the analysis. Weak H$\beta $ emission contaminates the H$\beta $ absorption index at radii > 25''.
(4) GMP 4822: Weak H$\beta $ emission contaminates the H$\beta $ absorption index at radii > 6''.
(6) GMP 2390: This galaxy hosts a kinematically decoupled, co-rotating core (see MSBW98). Weak, asymmetric NI emission contaminates the Mgb index inside 3''. Slight H$\beta $ emission contaminates the H$\beta $ absorption index at radii > 10''.
(7) GMP 2795: Weak H$\beta $ emission contaminates the H$\beta $ absorption index at 2'' - 4''. The mean $\sigma $ from J99 is significantly lower compared to our profile.
(8) GMP 3792: The inner "bump'' of the $\langle$Fe$\rangle$ index is caused by the varying focus of the spectrograph and could not be corrected sufficiently.
(9) GMP 2629: The mean H$\beta $ index from J99 is significantly higher compared to our profile, while $\sigma $ is significantly lower.
(11) GMP 2000: Weak H$\beta $ emission contaminates the H$\beta $ absorption index at 3'' - 6''.
(12) GMP 2413: Weak, asymmetric NI emission contaminates the Mgb index at 1''. The inner "bump'' of the $\langle$Fe$\rangle$ index is caused by the varying focus of the spectrograph and could not be corrected sufficiently.
(15) GMP 2417: The mean H$\beta $ index from J99 is significantly higher compared to our profile.
(18) GMP 4315: This galaxy shows strong and asymmetric H$\beta $ emission, which is demonstrated in Fig. 5a. Since no OIII emission is detected at all, these data clearly demonstrate that it is not possible to correct for H$\beta $ emission via OIII by applying the method suggested by G93.
(19) GMP 3073: The mean H$\beta $ and $\langle$Fe$\rangle$ indices from J99 are significantly higher compared to our profiles.
(20) GMP 1853: The mean $\sigma $ and $\langle$Fe$\rangle$ indices from J99 are significantly higher compared to our profiles.
(21) GMP 3201: Weak H$\beta $ emission contaminates the H$\beta $ absorption index at radii > 3.5''.
(22) GMP 3661: The $\langle$Fe$\rangle$ index profiles could not be corrected perfectly for the focus variation of the spectrograph.
(23) GMP 4679: The asymmetry in the $\langle$Fe$\rangle$ index is real. There is no evidence for emission or systematic errors in the continuum shape.
(24) GMP 3352: The Mgb and $\langle$Fe$\rangle$ index profiles could not perfectly be corrected for the focus variation of the spectrograph.The mean H$\beta $ index from J99 is significantly lower compared to our profile.
(25) GMP 2535: Weak H$\beta $ emission contaminates the H$\beta $ absorption index at radii > 4''.
(26) GMP 3958: The mean H$\beta $ index from J99 is significantly higher compared to our profiles.
(27) GMP 2776: The mean $\langle$Fe$\rangle$ index from J99 is significantly higher compared to our profiles.
(34) GMP 5568: This galaxy hosts a kinematically decoupled, counter-rotating core (see MSBW98).


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