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 gcAA99.tex Accepted by A and A
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\begin{document}

\title{ The Sgr~A$^*$ Stellar Cluster:
\\
 New NIR Imaging and Spectroscopy }

\author{Andreas Eckart
\and Thomas Ott
\and Reinhard Genzel}

\institute{Max-Planck-Institut f\"ur extraterrestrische Physik, Giessenbachstr.,
D-85740 Garching}

\begin{abstract}
We report preliminary results based on new near-infrared
 observations of the central stellar cluster of 
our Galaxy conducted with the infrared spectrometer ISAAC at the 
ESO VLT  UT1 and the MPE speckle camera SHARP at the ESO  NTT.
We obtained $\lambda$/$\Delta \lambda$$\ge$ 
3000 K-band spectroscopy of the 2.058 $\mu$m He~I, 
2.165$\mu$m Br$\gamma$ emission lines,
and 2.29 $\mu$m CO bandhead absorption line.
These data demonstrate clearly that there is no strong CO bandhead absorption 
originating in the northern part (S1/S2 area) of the central stellar cluster
at the position of Sgr~A$^*$. This makes it likely that these K$\sim$14.5 stars
are
O9 - B0.5 stars with masses of 15 to 20 M$_{\odot}$.
Weaker CO bandhead absorption in the southern part of the cluster (S10/S11 area) could be due to contributions from 
neighbouring stars.
We also report the detection of Br$\gamma$ line emission at the position of the 
central stellar cluster which could be associated with the 'mini-spiral'
rather than with the Sgr~A$^*$ cluster itself.
At the NTT we obtained another epoch epoch of proper motion measurments.
The changes of source positions are consistent with the proper motion
velocities derived from earlier epochs.

\keywords{galaxy:center -- galaxies:nuclei -- infrared:galaxies -- infrared:stars}
\end{abstract}


\end{document}