The MEG detector is designed to test Lepton Flavor Violation in the
μ+→e+γ decay down to a Branching Ratio of a few
10−13. The decay topology consists in the coincident emission of a
monochromatic photon in direction opposite to a monochromatic positron. A
precise measurement of the relative time te+γ​ is crucial to suppress
the background. The Timing Counter (TC) is designed to precisely measure the
time of arrival of the e+ and to provide information to the trigger system.
It consists of two sectors up and down stream the decay target, each consisting
of two layers. The outer one made of scintillating bars and the inner one of
scintillating fibers. Their design criteria and performances are described.Comment: Presented at the 12th Topical Seminar on Innovative Particle and
Radiation Detectors (IPRD10) 7 - 10 June 2010, Siena. Accepted by Nuclear
Physics B (Proceedings Supplements) (2011)tal