The calorimeter-seeded track reconstruction for the Mu2e experiment at Fermilab

The Mu2e experiment at Fermilab will search for the coherent μ→ e conversion on Al. The expected Mu2e single event sensitivity is 2.5 · 10
¹⁷
, an improvement of a factor 10 over the present limit. Mn2e takes advantage of a high intensity muon beam with more than 10
¹⁰
muons stopping in the target every second. The detector system is composed of a low-mass straw tracker and an crystal calorimeter. Efficient tracking and accurate reconstruction of the electron momentum are key components of the experiment We present a calorimeter-seeded pattern recognition strategy, which improves the tracking efficiency and makes the track finding more robust at high occupancy. We also describe a technique that reduces the non-Gaussian tails of the resolution by a factor close to three.