Today's Progress 17. May. 2007

Proton ID function on PB/NT arm : E570

Here, we define the proton ID function on PA-PB-NT system for E570 cycle data.

Formalization

In terms of the PAPB-measured 1/&beta, the PB+NT-measured total energy, T.E.(PB/NT), is represented as

T.E.(PB/NT) = f(1/&beta(PAPB)) .

for proton events. The function f(x) is phenomenologically obtained by fitting the correlation, and it is determined by the functional relationship between total energy VS 1/&beta, Birk saturation, PMT nonlinearlity, and so on. The proton ID function, PID, is then defined as

PID= T.E.(PB/NT) - f(1/&beta(PAPB)) (MeVee).

In E570, the function is defined arm-by-arm and cycle-by-cycle.

Cycle-by-cycle arm-by-arm correlation between 1/&beta and total energy for proton events.

The stability of the ID function has been checked run-by-run arm-by-arm.