Note to SciFi-Jan-Official.ppt. Last Update: Sat Feb 7 15:10:25 JST 2004 ------------------------------------- Basic Distributions (NEUT45/Neut43) ------------------------------------- * Page 3. P_mu, Theta_mu, and Q^2 distributions in 1-track sample. * Page 4. P_mu, Theta_mu, and Q^2 distributions in 2-track quasi-elastic (QE)-enhanced sample. * Page 5. P_mu, Theta_mu, and Q^2 distributions in 2-track Inelastic (nQE)-enhanced sample. MC=NEUT45 is shown in histogram. Histos in Green stand for MC prediction for quasi-elastic events. Note: - Quasi-elastic scattering: M_A=1.1 (GeV/c)^2. - Single pion production (Rein-Sehgal) M_A=1.1 (GeV/c)^2. - Cohrent-pion production is based on Rein-Sehgal (NPB223(1983)29¡¤but it is re-scaled by about 0.7, based on Marteau. NIMA451(2000)76. - DIS/multi-pion production rescaled by Bodek-Yang, NP B(Proc.Suppl.)112(2002)70. * Page 6. P_mu, Theta_mu, and Q^2 distributions in 1-track sample. * Page 7. P_mu, Theta_mu, and Q^2 distributions in 2-track quasi-elastic (QE)-enhanced sample. * Page 8. P_mu, Theta_mu, and Q^2 distributions in 2-track Inelastic (nQE)-enhanced sample. MC=NEUT43 (Official)=Ahn et al. PRL90(2003)041801. Note: - Quasi-elastic scattering: M_A=1.1 (GeV/c)^2. - Single pion production (Rein-Sehgal) M_A=1.2 (GeV/c)^2. - Cohrent-pion production is based on Rein-Sehgal (NPB223(1983)29¡¤but it is re-scaled by about 0.7, based on Marteau. NIMA451(2000) - DIS/multi-pion production rescaled by Bodek-Yang, NP B(Proc.Suppl.)112(2002)70. ---------------------- Tracking Performance ---------------------- * Page 10. Track length of 2nd track (Range) is reconstructed well for Nlayer>1. * Page 11. Track length of 2nd track is reconstructed well in both QE and nQE samples for Nlayer>1. * Page 12. Anglar distribution for 2nd track. DATA and MC(neut43) agree well for Nlayer=3 or more. * Page 13. Anglar distribution for 2nd track. DATA and MC(neut43) agree well for Nlayer=2. (Up to now, we have not used events with Nlayer=2 for physics analysis.) ----------------- PID performance ----------------- PID uses a cluster size (Npix) described fully in Suzuki etal.(K2K), NIMA453(2000)165. B.J.Kim etal. (K2K-SciFi), NIMA497(2003)450. has been measured to be proportional to the energy-loss of the charged particle. * Page 15. Cluster size (Npix) distributions for muon track and 2nd track (1st-4th Layers). Data and MC agree well for muons (MIP) and the 2nd traks (pions and protons) stopping in the SciFi detector. Npix increases as a particle stops (1st-4th layers ). * Page 16. Denifinion of the likelihood using cluster size distributions for pions and protons stopping in the detector. L_pi is the relative pion-like likelihood, normalized to 1. We apply this likelihood (L_pi) to separate pions and protons which stop in the SciFi detector. * Page 17. Efficiency of pions and protons as functions of L_pi. L_pi distributions are shown in Pages 18-20. * Page 18. L_pi distribution is shown for all 2nd tracks stopping in SciFi detector. - Data and MC (histogram) agree well. - MC predictions for protons, pions (+muons) and other particles (kaons,electrons etc) are shown in histogram of purple, blue and yellow color. - Tracks (Mis-reconstructed tracks) marked in red are either due to pions and protons which are not reconstructed well since they experience multiple-scattering and hadron interactions, or those where x and y- views which are required to make a good 3-dimensional track are mistakenly combined. - A MC track is recognized as "reconstructed" when at least two mc-to-reconstruct hit match exist in X fragment AND at least two hit match in Y fragment. "mis-reconstructed track" in the figure does not satisfy the condition. * Page 19. L_pi distribution is shown for 2nd tracks in 2-track QE enhanced sample. - Agreement is good. Notations are the same as before. * Page 20. L_pi distribution is shown for 2nd tracks in 2-track nQE enhanced sample. - Agreement is good. Notations are the same as before --------------------------- Study of Q2 distributions --------------------------- Q2 distributions for QE and nQE enhanced samples. They use only track information. * Page 22. Q2 distribution for 2track QE enhanced sample. - Quasi-elastic contribution is constrained in this sample. * Page 23. Q2 distributions for nQE enhanced sample. * Page 25. Q2 distribution for 2track nQE sample with proton-like requirement (L_pi < 0.1). - CC1pi contribution is constrained in this sample. * Page 26. Q2 distribution for 2track nQE sample with pion-like requirement (L_pi > 0.1). Coherent pion contribution is enhanced. - "Obserbed Q2 distributions are consistent with Neut43 in all of the plots (Pages 22-23,25-26)." Note (can be answered when asked at a workshop): We need coherent pion, ie Null cross section is unlikely. But, unless we understand the uncertainty of multi-pion/DIS, it is hard for us to separate 50% or 100% of Rein-Sehgal Coherent-Pion cross section. (fin)