Calorimeter construction

@ the Naples INFN & Physics Department assembling hall

The calorimetric bar is logically divided in 3 calorimetric cells ( $\sim 5 \times 4.4$ cm

cross section). The estimated cell thickness is 0.14 $\lambda_{I}$ and $1.14~ X_{0}$ . Every cell hosts 33 scintillating fibers ( 2 mm diameter Pol.Hi.Tech POLIFI 0244-3-200), each protected by a 1 mm thick plastic sheath. A Hamamatsu R4125 PMT (3/4 inch) working at a nominal gain G= $10^{7}$ is used to read-out the cell. For each bar a green LED, suitably coupled to 3 optical fibers, allows to send light pulses to the 3 PMTs, thus providing a tool for calibration and monitoring.

Thanks to the staff of the Mechanical Workshop