The ATLAS Tile Hadronic Calorimeter performance at the LHC

The Tile Calorimeter (TileCal), the central section of the hadronic calorimeter of the ATLAS experiment, plays a key role in detection of hadrons, jets and taus and for measurement the missing transverse energy. Due to the very good signal to noise ratio it assists the muon spectrometer in the identification and reconstruction of muons. TileCal is built of steel and scintillating tiles coupled to optical fibers and read out by photomultipliers. The calorimeter is equipped with systems that allow the monitoring and calibration of each stage of the read-out system using different signal sources: laser light, charge injection and a radioactive source. The performance of the calorimeter has been measured and monitored using calibration data, random triggered data, cosmic muons, splash events and more importantly LHC collision events. The results presented assess the absolute energy scale calibration precision, the energy and timing uniformity and the synchronization precision. The results demonstrate a very good understanding of the performance of the Tile Calorimeter that is well within the design expectations.