Na36 Time Projection Chamber: an interim report on a TPC designed for a relativistic heavy ion experiment

Since its conception in the early 1970s, the TPC has found application in several areas of particle physics ranging from e+e- collider experiments to rare decay studies of lepton nonconservation. A new and promising area of application for the TPC is the study of relativistic heavy ion collisions (RHIC). Presented here is an interim report on the first TPC for this field of physics, the NA36 TPC, being developed by Berkeley (LBL) for RHIC at the CERN SPS. Emphasis is placed on the operational and design considerations implemented to optimize the performance of the NA36 TPC in the study of central rapidity strange baryons produced in RHIC. The NA36 TPC volume is rectangular with an endcap area 0.5 m x 1.0 m and a maximum drift distance of 0.5 m. The drift volume is filled with Ar-CH4 (9%) at one atmosphere. A total of 6400 channels of time digitizing electronics instrument 66% of the endcap in a wedge shaped area matched to fixed target kinematics. 6 references, 5 figures