Preliminary results for the TB 08 VLE runs

Preliminary results for the TB '08 VLE runs with electrons Panos Katsas University of Athens CASTOR weekly meeting June 16 th 2008

Overview VLE runs with electron beam #48243 (E=2 Ge. V), #48319 (E=3 Ge. V), #48263, #48301 (E=5 Ge. V), #48266 (E=7 Ge. V), #48268 (E=9 Ge. V) 50 K events runs were selected Saleve side sector Muon contamination & beam profiles Particle ID with CK 2 Energy response linearity resolution comparison with high energy runs

H 2 VLE beam line CASTOR Cherenkov counters CK 3 filled with "Freon", P=1 Atm CK 2 filled with C 02, P=0. 4 atm CK 1 filled with Nitrogen (placed before the VLE beam line) Particle ID for VLE runs Muons: Muon Veto Back (MVB) Electrons: CK 2 (E<9 Ge. V), CK 3 (E<3 Ge. V) Protons, Kaons: CK 3 and TOF (E=1 -9 Ge. V)

Muon contamination Large μ- contamination >25% for E=2, 3, 5 Ge. V

Muon contamination (cont. ) E=3 Ge. V Run #48319 μ- peak e- peak cut applied in Muon Veto (back) counter

Beam profiles #48268 (9 Ge. V) #48301 (5 Ge. V) Beam not well focused wide spread over the Saleve sector #48266 (7 Ge. V) #48243 (2 Ge. V) beam profiles from WC-E

Signal in CK 2 9 Ge. V 7 Ge. V P=0. 4 atm P=0. 5 atm 5 Ge. V P=0. 2 atm 3 Ge. V 2 Ge. V P=0. 5 atm P=0. 3 atm P=0. 5 atm

Pressure scan with CK 2 e- beam runs (E=9 Ge. V): #48012 (P=0. 6) #48013 (P=0. 2) #48150 (P=0. 5) #48268 (P=0. 6)

PID with CK 2 E=5 Ge. V reminder: λmax = 0. 9 + 0. 36 ln. E (=1. 48 @ 5 Ge. V) CK 2 cut muons rejected P=0. 2 atm P=0. 5 atm (EM 1+EM 3+HAD 1) correlation between calo response & CK 2 signal for P=0. 5 atm

Calo response E=9 Ge. V E=2 Ge. V E=7 Ge. V E=3 Ge. V cut applied in CK 2 & Muon Veto Back counters

Calo response (cont. ) E=9 Ge. V E=7 Ge. V E=5 Ge. V E=3 Ge. V

Linearity & Resolution

Connection with high energy runs data points for E>9 Ge. V provided by Loukas ~48 counts/Ge. V VLE ~39 counts/Ge. V VLE lower mean signal by ~20% compared to the high energy runs

Summary VLE runs with electron beams were analysed Cuts applied only for the Muon Veto and CK 2 counters, to reject muons and pions respectively Significant muon contamination is observed & wide beam profiles low statistics for applying further cuts. . . Response is linear but the mean signal was found 20% lower compared to the high energy runs (E>9 Ge. V) To do: analyse VLE runs with pions