CMS track reconstruction and performance during $\mathit{pp}$ collisions at $\sqrt{s} = 7$ TeV

The trajectories of charged particles produced in LHC collisions are reconstructed in CMS and their momenta are measured in a 3.8 T solenoidal magnetic field. Reconstructed tracks in the inner Tracker are used to determine the position of the primary interaction vertex in the event and to monitor the position of the colliding beams. Furthermore the correct alignment of Tracker modules is vital for ensuring the reliability of the performance of the reconstruction. The alignment procedure was performed using several million reconstructed tracks recorded during the commissioning of the CMS experiment, both with cosmic rays and with the first proton-proton collisions at $\sqrt{s} = 7$ TeV. Tracks from collisions have also been used to reconstruct the hadronic decays of several mesons, including $K^{0}_{s}$, $\Lambda$, and $\Phi$. The performance of track reconstruction has been measured in the data and compared to the expectation from MonteCarlo simulation.