The tracking system for the Mu2e experiment

Mu2e will search for coherent, neutrino-less conversion of muons into electrons in the field of a nucleus to a few parts in 10−17, a sensitivity improvement of a factor of 104 over existing limits. To reach the goal the Mu2e tracker has to efficiently identify and measure electrons with momentum of 105 MeV/c, with a resolution of the order of ≲150 keV/c, reject a large amount of backgrounds (average hit rate of ∼15 kHz/cm2) and live in a high radiation environment (peak hit rate of ∼3 MHz/cm2). Moreover it must have the ability to work in a vacuum environment (at 10−4 Torr) and in a uniform magnetic field of 1 Tesla. We present the low mass straw based tracking device that is under development at Fermilab laboratory