1. N. Saoulidou (niki@fnal.gov). Fermilab 1 Update on track reconstruction in the Near Detector N. Saoulidou, Fermilab 1-29-04

2. N. Saoulidou (niki@fnal.gov). Fermilab 2 Outline Goal and strategy. Comparison between my new version of the code and the existing one using : My simple code Truth Helper Summary – On going work

3. N. Saoulidou (niki@fnal.gov). Fermilab 3 Goal & Strategy Goal : –Reconstruct the muon track from the “vertex” to the spectrometer region. Strategy : –a) Assume that event slicing is already done (process only single events were things are much more clear). –b) Correctly include all 4 different strip solutions with equal weights for the spectrometer region (CandStripSR) and then proceed with the tracking tuning various parameters to account for the specific characteristics if the Near Detector. After very useful discussions with Jim I managed to create a correct list of Candidate Strips for the spectrometer region (as well), that contain list of digits (my previous code was not handling this issue in a proper way).

4. N. Saoulidou (niki@fnal.gov). Fermilab 4 Examples of reconstructed muon tracks cont.

5. N. Saoulidou (niki@fnal.gov). Fermilab 5 Quantitative results of the track reconstruction (using my simple code for calculating the track quality and track reconstruction efficiency ). Percentage(%) of the reconstructed muon track strips that belong to the true muon track (for 5000 NEW Near Det. MC events and DetSim ), after considering –a) numu CC events with the neutrino vertex up to ~ 20 plates upstream the spectrometer region (just to make sure that the event is far enough from the spectrometer region) and –b) the muon track to have more than 5 planes The mean value of this distribution is ~ 85% for my code and ~ 82% for the current code. The percentage of numu CC events satisfying the previous criteria were no track was reconstructed is ~ 20 % with my code and 30% with the current code.(80 % of the mu CC events are reconstructed with my code and 70 % with the current code) My code Current code (Jims code)

6. N. Saoulidou (niki@fnal.gov). Fermilab 6 Quantitative results of the track reconstruction (using my simple code for calculating the track quality and track reconstruction efficiency ). The difference of the reconstructed momentum (using the SR fitter) and the actual muon momentum shows for both cases a shift which is slightly more pronounce using my code (statistics?). My code Current code SAME Fitter

7. N. Saoulidou (niki@fnal.gov). Fermilab 7 Quantitative results of the track reconstruction (using Truth Helper). The track purity is the same between the two versions. My code Current code

8. N. Saoulidou (niki@fnal.gov). Fermilab 8 Quantitative results of the track reconstruction (using Truth Helper) cont’d. The track completeness is much better with the current code BUT. This is contradicting (?) the results obtained with my simple code for calculating the track quality : –What I calculate is : –I would assume that this would correspond to the track completeness as calculated by the Truth Helper but apparently it is not ( need to investigate that…) My code Current code

9. N. Saoulidou (niki@fnal.gov). Fermilab 9 Quantitative results of the track reconstruction (using Truth Helper) cont’d. The track completeness (slc) is again better with the current code and in both cases it improves very little in comparison with the previous track completeness. My codeCurrent code

10. N. Saoulidou (niki@fnal.gov). Fermilab 10 Summary & On going work The track reconstruction efficiency (number of reconstructed tracks) of my version of the code is higher, as shown by both the Truth Helper and my simple code for calculating track reconstruction characteristics. The track purity of both version of track reconstruction appears to be the same using both Truth Helper and my simple code (for calculating track reconstruction characteristics.) However the track “completeness” (which is proportional to what I am calculating ) : –A) Is very different between the Truth Helper and my simple code and this needs to be investigate –B) Appears to be much better with the current version of the track reconstruction In order to come to a conclusion (related with which track reconstruction code is more efficient) I need to understand better the Truth Helper variable “ track completeness”.