All Figures

$\begin{figure} \par\includegraphics[width=6.7cm,clip]{1205fig1.eps} \end{figure}$ Figure 1: 270 s I-band image of FS373, a dE2,N in the NGC 3258 group. North is up, east is left.
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In the text

$\begin{figure} \par\includegraphics[width=6.7cm,clip]{1205fig2.eps} \end{figure}$ Figure 2: 300 s I-band image of FS76, a dE0,N in the NGC 5044 group. North is up, east is left.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{1205fig3.eps} \end{figure}$ Figure 3: Position of FS373 (asterisk) inside the NGC 3258 group. Small dots indicate the positions of the 375 group members listed in NED. Large dots indicate the positions of galaxies brighter than M_B = -20.
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In the text

$\begin{figure} \par\includegraphics[width=7.6cm,clip]{1205fig4.eps} \end{figure}$ Figure 4: Position of FS76 (asterisk) inside the NGC 5044 group. Small dots indicate the positions of the 160 group members listed in NED. Large dots indicate the positions of galaxies brighter than M_B = -20.
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In the text

$\begin{figure} \par\includegraphics[width=15.3cm,clip]{1205fig5.eps} \end{figure}$ Figure 5: Major-axis kinematics of FS373. a) velocity dispersion, b) mean velocity. The bottom panels zoom in on the central region around the KDC to show the velocity dispersion c) and mean velocity d) in more detail. The linear distance scale in kiloparsecs is indicated above the top panels (assuming H₀=70 km s^-1 Mpc^-1). The slit position on the sky is indicated in panel a). FS373 shows a pronounced bump in the mean velocity profile around $\sim$ 1'' and falls to zero at $\sim$ 2'' before rising again; this is characteristic of a KDC. The dispersion has a central depression, within the inner arcsecond, of $\sim$ 7 km s^-1, which could hint at the presence of a cold stellar disk.
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In the text

$\begin{figure} \par\includegraphics[width=15cm,clip]{1205fig6.eps} \end{figure}$ Figure 6: Major-axis kinematics of FS76. Same layout as in Fig. 5. The giant elliptical NGC 5044 is at a projected distance of 50 kpc towards the east (i.e. positive radii are closest to NGC 5044). FS76 shows a pronounced bump in the mean velocity profile around $\sim$ 0.8''. The velocity dispersion remains approximately flat at $\sim$ 50 km s^-1 within the inner 2'' and rises rather sharply outside this radius, indicative of a cold stellar disk.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm]{1205fig7.eps}\hspace*{3mm} \includegraphics[width=7.9cm]{1205fig8.eps} \end{figure}$ Figure 7: Photometry of FS373 ( left column), photometry of FS76 ( right column). From the bottom up: R-band surface brightness, $\mu _R$ , overplotted with the best fitting seeing-convolved Sérsic profile $\mu _R^S$ in grey; the residual from the Sérsic fit, $\Delta \mu _R =\mu _R - \mu _R^S$ ; ellipticity, $\epsilon = 1-b/a$ ; position angle, PA; and C₄, measuring the deviations of the isophotes from a pure elliptical shape (these photometric quantities have all been derived from the R-band image). Vertical dotted lines indicate the seeing FWHM. The central nucleus, which sits in the center of the outer isophotes, has been used as zero-point for the distance scale (we use the geometric mean of the semi-major and semi-minor axes of each isophotal ellipse, $\sqrt {ab}$ , as radius). The positivity of the C₄ parameter indicates that FS373 has disky isophotes. Top panels: R-I, V-R, and V-I color profiles as a function of major-axis distance a. For each color index, the image with the best seeing was convolved with a Gaussian to match the seeing of the other image (vertical dotted lines indicate where the seeing correction becomes important, with the V-R and V-I colors having a worse seeing (grey line) than the R-I color (black line) in the case of FS373). In the case of FS373, the V-band image suffers from variable extinction by thin cirrus, affecting the V-band surface brightness level but not the shape of the surface-brightness profile nor that of the color profiles. The uncorrected color profiles are drawn in full lines. The seeing correction is quite substantial, especially in the profiles involving the V-band image (0.2-0.3 mag). For FS76, the seeing corrections are small; 0.05 at most.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm]{1205fig9.eps} \end{figure}$ Figure 8: Simulated ellipticity profile of FS373. A flat disk with $\epsilon =1-b/a=0.9$ was added to a host galaxy with a flattening varying smoothly between $\epsilon =0$ in the very center and $\epsilon =0.23$ at 6'' and beyond. This model was then convolved with a Gaussian to simulate FWHM = 1.2'' seeing conditions and sampled with $0.2''\times 0.2''$ pixels in order to reproduce the FORS2 CCD sampling. Both the position angle and the surface brightness profile match the R-band characteristics of FS373. Without attempting to reconstruct the appearance of FS373 in detail, this toy model (grey full line) is able to reproduce the central rise of the observed ellipticity profile (black dots).
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In the text

$\begin{figure} \par\includegraphics[width=6.2cm,clip]{1205fig10.eps} %\end{figure}$ Figure 9: The strength of the Ca II triplet lines, corrected for contamination by the Pa lines, as measured by the CaT^* index along the major axis of FS373.
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In the text

$\begin{figure} \par\includegraphics[width=6cm,clip]{1205fig11.eps} %\end{figure}$ Figure 10: The strength of the Ca II triplet lines, corrected for contamination by the Pa lines, as measured by the CaT^* index along the major axis of FS76.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{1205fig12.eps} \end{figure}$ Figure 11: Major axis velocity dispersion and mean velocity of FS373 (panels a) and c), respectively) and of FS76 (panels b) and d)), folded around the center of the galaxy. The corresponding profiles of the best fit models are plotted with a full line. The models for FS373 were fitted to these kinematics. On the other hand, the models for FS76 were fitted directly to the spectra and are independent from the kinematics determined by a Gauss-Hermite fit to the LOSVDs. Still, the model agrees excellently with the kinematics, as it should of course.
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In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{1205fig13.eps} \end{figure}$ Figure 12: The distribution function of FS373 in the equatorial plane in turning-point space. The pericenter distance, $R_{\rm peri}$ , has the same sign as the z-component of the angular momentum, L_z. Circular orbits have $R_{\rm apo} = \pm R_{\rm peri}$ (dashed lines); radial orbits are characterized by $R_{\rm peri}=0$ (dotted line). The KDC is visible in phase-space as an excess of stars on near-circular orbits, indicated by an arrow.
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In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{1205fig14.eps} \end{figure}$ Figure 13: The distribution function of FS76 in the equatorial plane in turning-point space. The KDC is visible in phase-space as an excess of stars on near-circular orbits. Its locus is indicated by an arrow.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=8.5cm,clip]{1205fig15.eps} \end{figure}$ Figure 14: The estimated maximum change in the rotation velocity of a dwarf galaxy after an encounter with a giant elliptical of mass $M_2 = 5 \times 10^{11} M_\odot$ as a function of impact parameter b and axis ratio q. Full lines: FS373 (top to bottom: q=0.3, 0.5, 0.7), dotted lines: FS76 (top to bottom: q=0.5, 0.7, 0.9). We used $V_{\rm rel}=300$ km s^-1 in the case of FS76 and $V_{\rm rel} =400$ km s^-1 for FS373. Clearly, interactions with impact parameters smaller than $b \sim 20$ kpc can signifanctly change the streaming velocity of these slowly rotating systems.
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In the text

$\begin{figure} \par\includegraphics[width=6.7cm,clip]{1205fig1.eps} \end{figure}$	Figure 1: 270 s I-band image of FS373, a dE2,N in the NGC 3258 group. North is up, east is left.
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$\begin{figure} \par\includegraphics[width=6.7cm,clip]{1205fig2.eps} \end{figure}$	Figure 2: 300 s I-band image of FS76, a dE0,N in the NGC 5044 group. North is up, east is left.
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$\begin{figure} \par\includegraphics[width=8cm,clip]{1205fig3.eps} \end{figure}$	Figure 3: Position of FS373 (asterisk) inside the NGC 3258 group. Small dots indicate the positions of the 375 group members listed in NED. Large dots indicate the positions of galaxies brighter than M_B = -20.
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$\begin{figure} \par\includegraphics[width=7.6cm,clip]{1205fig4.eps} \end{figure}$	Figure 4: Position of FS76 (asterisk) inside the NGC 5044 group. Small dots indicate the positions of the 160 group members listed in NED. Large dots indicate the positions of galaxies brighter than M_B = -20.
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$\begin{figure} \par\includegraphics[width=6.2cm,clip]{1205fig10.eps} %\end{figure}$	Figure 9: The strength of the Ca II triplet lines, corrected for contamination by the Pa lines, as measured by the CaT^* index along the major axis of FS373.
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$\begin{figure} \par\includegraphics[width=6cm,clip]{1205fig11.eps} %\end{figure}$	Figure 10: The strength of the Ca II triplet lines, corrected for contamination by the Pa lines, as measured by the CaT^* index along the major axis of FS76.
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$\begin{figure} \par\includegraphics[width=8.6cm,clip]{1205fig14.eps} \end{figure}$	Figure 13: The distribution function of FS76 in the equatorial plane in turning-point space. The KDC is visible in phase-space as an excess of stars on near-circular orbits. Its locus is indicated by an arrow.
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