1. Kaons in the SPL Superbeam Antoine Cazes Laboratoire de L’accélérateur Linéaire

2. ECFA/Bene meeting - 19th of november 2003 Antoine Cazes Energy increase? Nominal energy of the SPL : 2.2GeV/c Maybe increase up to 4-5GeV/c (?) Better focusing Higher pions production This implies the study of many issues What is the flux of kaons What changes in the signal/noise Which is the best energy? Simulation of proton-target interaction The simulation chain for the energy optimization

3. ECFA/Bene meeting - 19th of november 2003 Antoine Cazes The simulation FLUKA 2002.4 500 000 pot kinetic energy T = 2.2 – 5 GeV (uniformaly distributed) target: Liguid Mercury (A=200.59, Z=80,  =13.546, X 0 =0.2756)  = 1.5cm L = 30cm (2 ) Particles are recorded when they exit the target

4. ECFA/Bene meeting - 19th of november 2003 Antoine Cazes kaon production at the exit of the target Two production processes (origin?) Anyway below 4 GeV, K + production < 300 times the  + production. neutrino production associated to K + seams to be negligeable. Number for 500 000 pot

5. ECFA/Bene meeting - 19th of november 2003 Antoine Cazes kaons angular distribution 2.2 GeV < Ep < 2.65GeV2.65 GeV < Ep < 3.1GeV3.1 GeV < Ep < 3.55GeV 3.55 GeV < Ep < 4GeV4 GeV < Ep < 4.45GeV 4.45 GeV < Ep < 5 GeV cos 

6. ECFA/Bene meeting - 19th of november 2003 Antoine Cazes The simulation chain p Fluka Geant 3 1) Proton interaction on target 2) Secondary particles tracking into the horn geometry? 3) decay tunnel   13 limit 5) Analysis  Available We need informations to complete the chain 4) Flux at Fréjus analysis input? Nufact-Note 134

7. ECFA/Bene meeting - 19th of november 2003 Antoine Cazes Conclusion Kaons may not be a problem: MARS? To optimize  13 sensitivity: we could change the SPL energy we need therfore retune the horn design but… Pieces are missing in the simulation the decay tunnel part A short note is available for whom is interested