All Figures

$\begin{figure} \includegraphics[width=12cm,clip]{5463fig1.ps}\end{figure}$ Figure 1: Regions around the three classical lines of neutral Technetium covered by the UVES spectra. The three upper panels show the stars with definite Tc detection and high signal-to-noise ratio, the fourth panel shows a star without Tc. The theoretical positions of the Tc lines are marked by the dotted vertical line. The synthetic spectra with and without Tc in the lower panel are based on a hydrostatic MARCS atmospheric model with $T_{\rm eff} = 3400$ K, [Fe/H] = -0.5, ${\rm log} (g) = 0.0$ , one solar mass, solar C/O ratio, and a microturbulent velocity of $\xi =2.5$ km s^-1. The spectrum with Tc was calculated with a Tc abundance of ${\rm log}({\rm A(Tc)}/{\rm A(H)}) + 12.0 = 0.0$ . The residual line at the position of the 4297 Å Tc line in the spectrum calculated without Tc is due to chromium. All spectra are normalised so that the mean over the respective plotted region is 1.0.
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In the text

$\begin{figure} \par\includegraphics[width=7.6cm,clip]{5463fig2.ps}\end{figure}$ Figure 2: Continuum-to-line flux ratios for the Tc lines at 4238 Å and 4262 Å. For the former, the flux between 4239.4-4239.7 Å (continuum) was ratio-ed to the flux in the range 4238.0-4238.3 Å (line), while for the latter the wavelength ranges were 4261.3-4261.5 Å and 4262.1-4262.3 Å, respectively (see also Fig. 1). Six to ten pixels are typically covered by these ranges. We include the field stars R Hor and ER Vir (analysed in Paper I) for this plot. Also the star M1147 separates quite clearly from the compact group of stars without Tc. This star was not suspected to have Tc from the visual inspection of its spectrum (due to the low SNR). The filled diamond symbols represent the flux ratios derived from the synthetic spectra plotted in Fig. 1.
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In the text

$\begin{figure} \par\includegraphics[width=7.5cm,clip]{5463fig3.ps}\end{figure}$ Figure 3: Period-K magnitude diagram for our sample of long-period variables in the galactic bulge. Squares and triangles represent Mira and semiregular variables, respectively. The filled symbols are stars with a positive Tc detection. The solid line is the period-K relation from Glass & Schultheis (2003).
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In the text

$\begin{figure} \par\includegraphics[width=8.3cm,clip]{5463fig4.ps}\end{figure}$ Figure 4: Colour-luminosity diagram of the sample stars, with symbols the same as in Fig. 3. In the upper panel, the luminosities are plotted as directly derived from the near infrared photometry, whereas in the lower panel the luminosity is corrected for the depth-induced scatter using Fig. 3. The dotted horizontal line marks the minimum luminosity at the stage where 3DUP sets in. Isochrones from Girardi et al. (2000) are also represented in solid and dashed lines (see legend). For both isochrones, the tip of the AGB is well below the observed AGB tip. The thick line in the lower panel is a 1.5 $M_{\odot }$ evolutionary model track from Straniero.
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In the text

$\begin{figure} \par\includegraphics[width=7.7cm,clip]{5463fig5.ps}\end{figure}$ Figure 5: Bolometric magnitude versus period of the sample stars. Again, the symbols are the same as in the previous figures. The dotted horizontal line marks the minimum bolometric magnitude at the stage where 3DUP sets in. The solid lines are relations for a 1 $M_{\odot }$ (lower line) and a 1.5 $M_{\odot }$ (upper line) model star pulsating in fundamental mode (Wood & Sebo 1996).
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In the text

$\begin{figure} \par\includegraphics[width=7.5cm,clip]{5463fig3.ps}\end{figure}$	Figure 3: Period-K magnitude diagram for our sample of long-period variables in the galactic bulge. Squares and triangles represent Mira and semiregular variables, respectively. The filled symbols are stars with a positive Tc detection. The solid line is the period-K relation from Glass & Schultheis (2003).
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$\begin{figure} \par\includegraphics[width=7.7cm,clip]{5463fig5.ps}\end{figure}$	Figure 5: Bolometric magnitude versus period of the sample stars. Again, the symbols are the same as in the previous figures. The dotted horizontal line marks the minimum bolometric magnitude at the stage where 3DUP sets in. The solid lines are relations for a 1 $M_{\odot }$ (lower line) and a 1.5 $M_{\odot }$ (upper line) model star pulsating in fundamental mode (Wood & Sebo 1996).
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