The PHENIX Muon Arms detect vector mesons decaying into muon pairs, to
allow the study of the Drell-Yan process, and to provide muon detection
in 
, in the relativistic heavy ion and spin physics
programs of PHENIX. Each muon arm must track and identify muons, as well
as provide good rejection of pions and kaons; therefore, both a Muon Tracker
(
Tr) and
a Muon Identifier (ID) are needed. Each arm of the Muon Tracker comprises three stations
of tracking chambers, with three cathode strip chambers each, mounted inside
the end-cap muon magnets. The chamber design uses a special mounting structure
to minimize the impact of the motion of the magnet on the chambers and to
reduce acceptance losses. A survey system for monitoring chamber positions
in real time is an integral part of the tracking system. Two different construction
techniques are being used for the Tr chambers: the first and last stations are constructed
as honeycomb panels with cathode strips on the inside surfaces and the central
stations are constructed as stacks of wires and etched metallized foils
attached to aluminum frames.