Speaker
Giulio Saracino
(Univ. Degli Studi di Napplo Federico)
Description
The P326 experiment at CERN aims to a very rare decay, K + → π +νν,
immersed in a overwhelming K + → μ +ν, K+ → π +π0 (and other decays)
background. This calls for an impressive rejection capability (10 12) in order
to keep a significant signal/background ratio while keeping a good overall
efficiency. One of the key components of the detector is the photon veto
system which should have a global π 0 inefficiency of 10−8 or better and
should almost hermetically cover the decay volume down to zero degrees.
The detectable energies range from about 100 MeV to almost 70 GeV. The
photon veto system will be composed by a large angle veto system, in the
form of 12 rings installed along the decay region and covering angles larger
than 50 mr, by the NA48 Liquid Krypton Calorimeter for intermediate angles
and by Intermediate Ring Calorimeters and a Small Angle calorimeter to
close the acceptance at small angles. An intense R&D program for these
detectors is progressing. Prototypes of the large angle vetoes and of the
Small Angle Calorimeter have been built. A run with a tagged photon beam
at CERN has been performed to measure the LKr calorimeter inefficiency to
photons down to about 4 GeV. The talk will review the various components
of the system and present the latest results on the tests of the prototypes.
Primary authors
Giulio Saracino
(Univ. Degli Studi di Napplo Federico)
Riccardo Fantechi
(INFN Pisa)
