Definition of Total Transverse Energy


The CDF definition of the total transverse energy (Total-Et) exploits the cell structure of the CDF calorimeters. To obtain more information on the CDF detector click here. In the following the transverse energy (Et) is defined: Et = E sin(theta), where E is the jet (or calorimeter cell) energy and theta is the angle between the beam direction and the direction of the jet (or vector pointing from the interaction vertex to the calorimeter cell). In the 1988/9 data sample the Total-Et was defined as a sum over calorimeter cell Et, and the definition was therefore independent of the "jettiness" of an event. In the 1992/3 data taking period the luminosity of the Tevatron collider was sufficiently large that the contribution from multiple interactions became significant if the 1988/9 definition of Total-Et was used. To overcome this difficulty, the 1992/3 definition of Total-Et is based on a sum over the Et of jets.

1992/3 Definition of Total Transverse Energy

Total-Et is defined as the scalar sum of the transverse-energies (Et) of all jets with Et > 20 GeV reconstructed in the CDF calorimeters. Jets are reconstructed using the CDF jet reconstruction algorithm with a cone radius of 0.7 in (pseudorapidity, azimuthal-angle)-space.

1988/9 Definition of Total Transverse Energy

Total-Et is defined as the scalar sum of the transverse-energies (Et) recorded in all the calorimeter cells of the CDF detector in which Et exceeds 500 MeV.