ATLAS B-Physics Results with First Data

First data of ATLAS will allow several B-physics related analyses. Already with 10 $mathrm{pb}^{-1}$, the cross section of heavy quarkonia like $J/psi$ and $Upsilon$ will be measured in a $p_T$ range from 10-50 GeV/c. The $J/psi$ and $Upsilon$ polarization is expected to be measured with a precision of 0.02 to 0.06 and 0.2 for $Upsilon$, respectively. Another measurement with first data will be the estimation of the cross section of the exclusive decay $B^+ ightarrow J/psi K^+$, which will be used as a reference channel for e.g. rare B-decay searches as well as for detector performance studies. For the later the decay processes $B^0_s ightarrow J/psi Phi$ and $B^0_d ightarrow J/psi K^{0*}$ will be important. The measurement of the invariant masses of the B-mesons and lifetimes using these decays will allow detector performance checks and to study the potential of flavor tagging algorithms, which are crucial for other B-physics related analyses.