1. P0D reconstruction/analysis update
LE PHUOC TRUNG

2. Software activities A new stable release of nd280 for TPC test beam
MDC0 status: waiting to access the MC datasets
P0D software:
Continued reconstruction work: improve 0 purity, working on improving 0 reconstruction.
Electron neutrino reconstruction: wait for kinematics files from H. Tanaka.
Testing the midas (electronics output format) to root converter.
Prepare software for cosmic data processing: reconstruction, calibration constant calculation.

3. Muon decay tagging update
58 ns
Beam
After spill
100 ns
MUON DECAY TAGGING
CC  interaction, - not reconstructed
P0D
xz or yz
Clustering seed
Later bunches
After spill
Expand clustering seed into later hits, hits added to the cluster are decay hits
Make sure decay hits are distance connected 9cm, time connected 20ns
Event with 2 or more decay hits is considered CC interaction.
Tagging efficiency 50%, including muon capture, next slide
Before 37%, bug

4. Muon capture Muon capture also produces delayed hits
4000 decays
4000 captures
Composition of delayed hits
Muon generated at 0.0 ns, plot from ns
Neutron spectrum
From nucleus de-excitation,
GEANT4 ‘not ideal’
Delayed hits from muon capture
MeV

5. Delayed hits from NC single 0 production
16,000 single NC 0
not understood
NC single 0 can be mistaken as muon decay

6. Short track detection Detect the longer side using Hough transform
Make that the longer side is muon-like by counting the number of hits in each layers.
Find the short side by angular scanning at both ends of the longer side. The short side appear as a peak in the angular histogram.
Make sure that the open angle > 15 degrees, and no more than 2 hits within the open angle.
Make sure that there are fewer than 5 remaining hits not associated with the V.
First found by the Hough transform
Angular histogram around these points

7. 0 purity update MC: single NEUT /spill, 100,000 spills
Include the new muon decay tagging
Include the short track detection
Efficiency: 18%
Purity: ~ 47%
21%
before 35%
32%
47%
Reconstructed Energy (MeV)

8. Efficiency loss by different cuts
Charged-current - rejection efficiency 99.8%
===========================================
Particle  -
All
Muon-like cut
Unmatched
Muon decay cut
Low hits cut
Shower cut
Invariant cut
Fiducial cut
counts %  0 loss by cuts
CUTS
15%
Room for efficiency improvement

9. 0 reconstruction challenge

10. 0 reconstruction summary
Current implementation was originally written by K.Kobayashi, partly rewritten by Clark/Trung.
Work need to be done:
Improve vertex finder
Energy reconstruction/calibration
Energy leaking study
Deviation from true vertex
 ~ 3cm
 ~ 4cm
 ~ 0.1
Energy resolution, 350 MeV, fully contained 0

11. SUMMARY Improve muon decay tagging
Neutrons in NC interactions cause 0 mistaken as muon decay.
Short track detection
What needs to be improved: 0 reconstruction