Trapping Fraction Barrel DIRC

For the fast simulation as well as for the PID Tag the trapping fraction has been determined as a lookup table (root TH2F). Shown is the fraction of the initially produced Cherenkov radiation as a function of the incindent particles momentum and polar angle.

To illustrate the influence of the particles mass and the magnetic field, animated gifs have been produced, which show the fractions change due to these quantities.

Influence of particles mass

• DIRC barrel trapping fraction dependent of mass:
  

Influence of the magnetic field H (example for kaons)

• DIRC barrel trapping fraction dependent of magn. field:
  

-- KlausGoetzen - 21 Apr 2008