Characterization and commissioning of the ATLAS micromegas quadruplet prototype

Micromegas (Micro Mesh Gaseous Structure) chambers have been chosen for the New Small Wheel (NSW) project, the upgrade of the forward muon spectrometer of the ATLAS experiment both to provide precision tracking and contribute to the trigger. A quadruplet (1m $\times$ 0.5m) has been built at the CERN laboratories, it will serve as prototype for the future ATLAS chambers. This detector is realized using resistive-strip technology and decoupling the amplification mesh from the readout structure. The four readout planes host overall 4096 strips with a pitch of 415 $\mu m$. A complete detector characterization carried out with cosmic rays, X-Ray source and dedicated test beam is discussed. Characterization is done using analog front-end chip (APV25). The efforts that lead to the chamber construction and the preparation for the installation in the ATLAS experimental cavern are presented. Finally, an overview of the readout system developed for this prototype, and integration into the ATLAS Data Acquisition System is provided