  The Compact Muon Solenoid (CMS) detector is one of two general-purpose
detectors that reconstruct the products of high energy particle interactions at
the Large Hadron Collider (LHC) at CERN. The silicon pixel detector is the
innermost component of the CMS tracking system. It determines the trajectories
of charged particles originating from the interaction region in three points
with high resolution enabling precise momentum and impact parameter
measurements in the tracker. The pixel detector is exposed to intense ionizing
radiation generated by particle collisions in the LHC. This irradiation could
result in temporary or permanent malfunctions of the sensors and could decrease
the efficiency of the detector. We have developed procedures in order to
correct for these effects. In this paper, we present the types of malfunctions
and the offline calibration procedures. We will also show the efficiency and
the resolution of the detector in 2012.
