DELPHI experiment

[1][2] The specific focus of DELPHI was on particle identification, three-dimensional information, high granularity (detail), and precise vertex determination.

In operation, electrons and positrons from the accelerator went through a pipe going through the center of the cylinder, and collided in the middle of the detector.

[7] The VD is an advanced silicon detector closest to the collision point, and has the purpose of providing precise tracking.

[10] The two parts of the detector are the JET drift chamber and the trigger layers (TL), producing points per track and polar angle coverage.

[7] The gas used in the JET chamber is mostly CO2, with a small amount of isobutane, which allows signals caused by incoming particle tracks to arrive at the same time.

[6] DELPHI is able to use the Ring Imaging Cherenkov technique to differentiate secondary charged particles produced by collisions.

The high-density projection chamber (HPC) was a barrel electromagnetic calorimeter mounted on the inside of the solenoid outside the OD.

To measure the luminosity, the number of events of a known process must be counted, which in the DELPHI experiment was chosen to be Bhabha scattering at small angles.

[21] Furthermore during the LEP1 data taking runs in 1989-1995, hadronic and leptonic decays of the Z boson at 91 GeV were investigated and the widths of different branches were obtained.