The Cluster



The basic element of ARGO-YBJ are RPCs of dimensions 126 X 285 cm2. The detector is organized in modules of 12 chambers whose dimensions are 764 X 572 cm2.This group of RCPs represent a logic subdivision (CLUSTER) of the apparatus
 

The detector consists of 130 CLUSTERs (1560 RPC) in the central part and 24 CLUSTERs (288 RPC) in the guard ring for a total of 1848 RPCs. The proposed lay-out allows to achieve an active area of about 95 % the total.

The trigger and DAQ systems are organized in two levels, a Local Station that collect and manage the information of one CLUSTER (12 chambers), and a Central Station that collects the information from the local stations and provides the trigger and manages the data collection.

The Local Station is dedicated to the acquisition of information generated by four groups of three chambers each (in total 120 pads, 8 strips each). This local stations, placed on the geometrical center of 6 by 2 chambers, consists of four Signal Processing Cards plus one Control and Communication Card.