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Reconstruction of neutrino interactions in PEANUT in general scanning (unbiased) mode. Giovanni De Lellis on behalf of Andrea Russo Naples University. PEANUT detector. Neutrino beam and Cosmic ray exposure. BL033. All 57 plates have been general scanned:. Scanning areas. 38 plates
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Reconstruction of neutrino interactions in PEANUT in general scanning (unbiased) mode Giovanni De Lellis on behalf of Andrea Russo Naples University
PEANUT detector Neutrino beam and Cosmic ray exposure BL033
All 57 plates have been general scanned: Scanning areas 38 plates have been general scanned: 5.55 x 4.30 cm^2 = 23.9cm^2 11.1 x 4.30 cm^2 = 47.8 cm^2 General scanning mode Measured density of aligned base-tracks: 4 base-track / mm2 (transportation order) 0.7 base-track / mm2 (assembly order)
PEANUT emulsions Transportation order Beam exposure
s ~ 5 mrad s ~ 8 mm s=13 mrad Micro-track angular resolution Track reconstruction Position and angular resolution in the plate to plate alignment Consecutive base-track accuracy
s = 0.7mm s = 3mrad Base-track resolution: spatial and angular difference between a base-track and the corresponding volume track
Track reconstruction in transportation order Density of aligned base-tracks~4/ mm2
Characterization of the tracks in transportation order High ionizing power (at least 10 segments in the following plots) High tracking efficiency Due to low momentum protons (~100MeV)
Beam tracksat least 4 segments in the plots shown Density of aligned base-tracks~0.7 / mm2 NuMI beam peak (x, y) ~ (-50,0) mrad Tracking efficiency MIP particles: <Grain number> ~ 24
x y tx ty Emulsion-SFT matching • sx = 1190 mm • sy = 1240 mm • stx = 5 mrad • sty = 8 mrad Angular misalignment
Brick rotation Top View beam = 24 mrad 2.4 mm brick z depending on the position z SFT planes
sx = 605 mm • sy = 443 mm • stx = 6 mrad • sty = 5 mrad Emulsion-SFT matching after z correction
IP z ~ 60% up to 10 µm Impact parameterand z distributiontrack to vertex longitudinal distance
Neutrino event identification 62278 volume tracks reconstructed Single track events Multiple track events • 11765 made of more than 4 base-tracks • 171 confirmed by SFT • 17 with UP > 3 • 2995 vertices reconstructed • 658 with all forward tracks • 17 confirmed by SFT (154 “z versus IP” ) • 7 pass the “z versus IP” cut MC Multiplicity Identification of 24 neutrino interactions in the fiducial volume
“High” multiplicity events not matching the SFT Preliminary Multiplicity 9!
Expected number of events in the brick Neutrino interaction rate in an iron target exposed to NuMI in the near hall (2 * 105) / (year * ton) This value (increased by 8%) accounts for the lead target 43 ± 7 neutrino interactions expected in the analyzed volume Nmes/etotal = 44 ± 9 neutrino interactions estimated from the 24 observed events after efficiency correction
Conclusions • A volume of 413 cm3 (58% of the brick volume) was general scanned in one PEANUT brick • Detailed single brick Monte Carlo simulation of PEANUT used to define a procedure to identify neutrino interactions • 24 neutrino interactions with SFT matching have been identified in the volume • After the efficiency correction, we estimate (44 ± 9) neutrino interactions happening in the volume • Good agreement with the number of expected events (43 ± 7) computed from the flux • 8 events with larger multiplicity found without any match with the SFT (6 with 3 tracks, 1 with 4 and 1 with 9 tracks)