Y. Hayashide

CDF end plug electromagnetic calorimeter using conductive plastic proportional tubes

Abstract A 2.8 m diameter and 50 cm deep round disc-shaped calorimeter has been built for each of the forward and the backward opening of the central detector structure of the Collider Detector at Fermilab (CDF) using conductive plastic proportional tube arrays sandwiched with lead absorber panels. A thorough use of cathode readout based on pads and strips etched on the printed circuit boards on the chambers enabled us to construct a finely segmented projective tower geometry defined by a polar coordinate system with the origin at the center of the detector with minimum dead region. These modules were tested for various properties with high energy electron beams and completely mapped with 100 GeV electron beams. The response map was then used as the input for a χ 2 -minimization procedure and an improved uniformity of 1.3% rms was obtained. A factor of 500 to 1000 rejection of pions was obtained using a correlation matrix without relying on a momentum measurement.

A gas sampling calorimeter using conductive plastic tubes (II)

Abstract A prototype module for the electromagnetic shower calorimeter has been constructed and its characteristics have been measured. It consists of 38 layers of planar proportional chambers interleaved with 3 mm thick lead plates. The proportional chamber is made of conductive plastic tubes as a dc cathode and pickup electrodes as an rf cathode. The pickup electrodes are copper-clad G-10 panels etched with finely segmented patterns which, when assembled, form complete conical towers. The module was tested using high energy electron and hadron beams of energy range from 25 GeV to 150 GeV. Energy resolution is 24% E( GeV ) , and the position resolution is 1.5 mm or better at and above 50 GeV. The lateral and longitudinal distributions of the energy deposit are studied and they are applied to π e discrimination.

π/e separation with prototype CDF end plug gas calorimeters

Hadron rejection against electron signal of a combined system of electromagnetic and hadron calorimeter has been studied. Data was taken at M4 beam line of Fermilab at energies from 25 GeV to 150 GeV. Hadron rejection of electromagnetic calorimeter is greatly improved by the use of hadron calorimeter information. The details of the results are discussed.