All Figures

$\begin{figure} \par\includegraphics[width=17.3cm,clip]{6265fg01.eps} \end{figure}$ Figure 1: Left: L'-band image of the central part of the Milky Way ( $\sim$ 18 $\times$ 18 arcsec²). The image contains a large number of dust embedded stellar sources, mini-spiral emission and several previously unknown thin filaments. The image has a pixel scale of 27 mas/pixel and resolution $\sim$ 100 mas. Right: high-pass filtered (smooth-subtracted) version of the image shown on the left. Here all compact features are enhanced. Cross in both images marks the position of SgrA*.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{6265fg02.eps} \end{figure}$ Figure 2: Identification of the thin features observed in the the L'-band. SgrA* is located at the center of the image. We have marked the line of nodes for disk (i) at a position angle of 28 $^\circ$ on the sky (N to E) that contains the Northern Arm in the model by Vollmer & Duschl (2000).
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{6265fg03.eps} \end{figure}$ Figure 3: High-pass filtered image with the narrow features labeled.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=16cm,clip]{6265fg04.eps} \end{figure}$ Figure 4: Left: L'-band ( up) and $K_{\rm S}$ -band ( down) image of the small area southwest from SgrA* (axes show the offset from SgrA*). Arrows mark the X7 feature in the L'-band and a star at the same position in the $K_{\rm S}$ -band frame. Right: L'-band image containing X3, X7 and SgrA*.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=15.5cm,clip]{6265fg05.eps} \end{figure}$ Figure 5: L'-band image of the Galactic Center. Boxes mark thin filaments with measurable proper motions. Note that boxes in this image are different from those used for measurements (stated in Table 1). The arrows show proper motions of the thin filaments obtained in our study: light blue arrows stand for the features with measurable proper motion in both directions, while black arrows show only the proper motion component perpendicular to the feature (see the text for the explanation). The insignificant motion of the Northern Arm filament NE1 is marked with a circle rather than an arrow. The cross marks the position of SgrA*.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{6265fg06.eps} \end{figure}$ Figure 6: Proper motions of thin filaments. The error bars show the 1 $\sigma$ uncertainty of each measurement. The x and y components mentioned in graphs refer to RA and Dec, respectively.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{6265fg07.eps} \end{figure}$ Figure 7: The Pa $\alpha$ map with the Keplerian orbits overplotted (Paumard et al. 2004). We additionally sketch some of the L'-band narrow filaments, showing that none of the orbits is aligned with the Northern Arm filaments.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{6265fg08.eps} \end{figure}$ Figure 8: Results of our preliminary 3D dynamical model calculation. Three particles (marked +, $\times$ and *) have been placed within the mini-spiral with locations and velocities consistent with our current knowledge. See text for further explanation. The dashed lines connect particles launched at equal times. The time beetween the sets of symbols is $\sim$ 250 yr. The solid lines represent the observed narrow features (i.e. shock fronts or contact surfaces) and how they evolve while travelling along the Northern Arm/Bar region. A filament formed at some position in the Northern Arm or Bar is slightly changing the shape while drifting with the rest of the material, but preserves its filamentary appearance.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{6265fg09.eps} \end{figure}$ Figure A.1: L'- and $K_{\rm S}$ -band stellar proper motion difference vs. L' magnitude. The y-axis labels are calculated via $\vert$ $\vec{v_K}$ - $\vec{v_L}$ $\vert$ / $\sigma$ ( $\vert$ $\vec{v_K}$ - $\vec{v_L}$ $\vert$ ), where $\vec{v_K}$ and $\vec{v_L}$ represent the proper motion of a star as measured from $K_{\rm S}$ - and L'-band frames, respectively, and $\sigma$ ( $\vert$ $\vec{v_K}$ - $\vec{v_L}$ $\vert$ ) represents the standard deviation of the difference between two measurements. We find that 97 $\%$ of all the sources lie below the 3 $\sigma$ line.

In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{6265fg10.eps} \end{figure}$ Figure A.2: $K_{\rm S}$ - and L'-band proper motion difference projected in RA and Dec.

In the text

$\begin{figure} \par\includegraphics[width=8.1cm,clip]{6265fg11.eps} \end{figure}$ Figure B.1: Upper panel: difference image of the area around the filament NE4, between the epochs 2006.408 and 2003.356. White pixels correspond to the later epoch, thus indicating the south-westward motion of the filament. Lower panel: grayscale image of the same area (2003.356) with the contours corresponding to the 2006.408 (black) and 2003.356 epoch (white) overlayed. Contour levels correspond to the 50, 60, 70 and 80% of the maximum intensity of the image (both images were previously scaled to have the same maximum intensity).

In the text

$\begin{figure} \par\includegraphics[width=7.7cm,clip]{6265fg12.eps} \end{figure}$ Figure C.1: Sketch of the outflow model. Collimated outflow originating from the mass-losing stars cluster and possibly the black hole at the position of SgrA* could, in the interaction with the material of the mini-spiral, explain the geometry and motions of the thin filaments. This model suggests that northern and southern lobes of the CND are associated with the outflow.

In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{6265fg13.eps} \end{figure}$ Figure C.2: Positions of main features at the Galactic Center as seen by an observer at the center of the Galaxy. Two crosses indicate the normal to the clockwise stellar disk plane: disk A as found by Levin & Beloborodov (2003) and disk B by Paumard et al. (2006). The large light-gray-shaded area south of the galactic plane represents the results from NIR polarization measurements as presented by Eckart et al. (2006) and Meyer et al. (2006b,a). Here we only show the direction towards the Northern Arm. The dark-gray-shaded area close to the center of the plot outlines the approximate direction of a possible collimated outflow that could explain out new observations plus the H₂ results by Burton & Allen (1992); Gatley et al. (1986,1984) and Yusef-Zadeh et al. (2001). Such an outflow would also be in agreement with mass-loss from the the stellar disks and the recent polarization data (see references above).

In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{6265fg02.eps} \end{figure}$	Figure 2: Identification of the thin features observed in the the L'-band. SgrA* is located at the center of the image. We have marked the line of nodes for disk (i) at a position angle of 28 $^\circ$ on the sky (N to E) that contains the Northern Arm in the model by Vollmer & Duschl (2000).
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{6265fg03.eps} \end{figure}$	Figure 3: High-pass filtered image with the narrow features labeled.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=16cm,clip]{6265fg04.eps} \end{figure}$	Figure 4: Left: L'-band ( up) and $K_{\rm S}$ -band ( down) image of the small area southwest from SgrA* (axes show the offset from SgrA). Arrows mark the X7 feature in the L'-band and a star at the same position in the $K_{\rm S}$ -band frame. Right: L'-band image containing X3, X7 and SgrA.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{6265fg06.eps} \end{figure}$	Figure 6: Proper motions of thin filaments. The error bars show the 1 $\sigma$ uncertainty of each measurement. The x and y components mentioned in graphs refer to RA and Dec, respectively.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{6265fg07.eps} \end{figure}$	Figure 7: The Pa $\alpha$ map with the Keplerian orbits overplotted (Paumard et al. 2004). We additionally sketch some of the L'-band narrow filaments, showing that none of the orbits is aligned with the Northern Arm filaments.
Open with DEXTER