Intra-String Muon Timing Dmitry Chirkin, LBNL

Method of verification For a given string choose a DOM X Reconstruct data using hits on the chosen string excluding hits in DOM X Find a maximum in the distribution of time residuals of the leading hits in DOM X from the reconstructed tracks For tracks passing sufficiently close to the DOM X this maximum should be close to zero DOMs not functioning properly will have suspicious residual distributions

Dataset 14 days (last week of February and first week of March) of PnF data was used. E.g. ~14/50=6.7 hours of data Although tcal file were available for some runs, no time recalibration was performed for consistency events with multiplicity 8 were extracted from the .hit files and compressed into new_ .hit files to minimize network file access to the data when running on multiple nodes Calculation was performed on 60 npx 1 GHz nodes, took about 42 hours per node, 2520 cpu-hours alltogether

Quality cuts Data was analyzed with and without quality cuts, e.g. for early data Feb 1: http://icecube.wisc.edu/internal/IceVer/Meetings/1Feb06/muon Final results are based on the analysis with quality cuts:  distance d1,2 from reconstructed track to DOM: 10 meters  zenith angle 170<th1,2<180  zenith angle quality: -3<th2-th1<3  reduced llh: rllh1,2<6.5 All given for track reconstructions:  1 (simple track) and  2 (joint positional-energy track).

Residual distribution fits

String 21 60 DOMs working no significal outliers rms=1.90

String 29 58 DOMs working insufficient statistics for DOM 58 DOMs 59 and 60 are missing rms=1.82

A DOM with insufficient statistics

String 30 59 DOMs working (DOM 23 missing) DOMs 45, 46, 47, 48, 49, 50, 51, 52 have insufficient statistics rms=3.11: somewhat high due to many failing fits

String 38 58 DOMs working no significal outliers insufficient statistics for DOM 58 DOMs 59, 60 missing rms=2.22

String 39 56 DOMs working DOMs 1, 21, 22, 23, 24, 60 have insuffivient statistics rms=2.21

String 40 56 DOMs working DOMs 45, 46, 47, 48, 53, 54, 55, 56, 57, 58, 59, 60 have insufficient statistics rms=3.46: somewhat higher due to many failing fits

String 49 60 DOMs working DOMs 17, 18, 19, 20, 29, 32, 33, 34, 35, 36, 59, 60 have insufficient statistics rms=2.72

String 50 51 DOMs working no significal outliers rms=2.33

String 59 58 DOMs working DOMs 57, 58 have insufficient statistics rms=1.90

Summary string 21: 60 DOMs present in data 60 confirmed alltogether 516 DOMs present in data; 472(491) confirmed

Muon verification web page