Event ID comparison




Introduction

Before disscussing the inconsistency of the shift obtained from the 2nd cycle data, it must be checked the data sets are correctly selected. In order to confirm the vertex cut events are included in the no vertex cut events, their event IDs in all runs are verified.


Comparison of event IDs in two ntuples

There are two types of ntuples, with vertex cuts and without vertex cuts. The event ID corresponding to an event in a run is filled in the ntuples. If an event is filled in two ntuples at the same time, the ntuples must have same ID for the event.

Results : It is confirmed that all signal events filled in the ntuple with vertex cuts are included in that of without vertex cuts. But several tens of event IDs are out of synchronization. This means several tens of IDs assigned by the analysis program pass each other, but the events are filled in the other ntuple as different IDs. This reason isn't known yet. (05/July/2006)