Delta Phi Correlations

Mixed Event &Delta&phi Correlations

The &Delta&phi correlation plots below have been generated with a rotating stack of 10 events grouped by zVertex bin (12 bins from -30 to 30 cm), 24M events have been run over.

The &phi from a seed in the current event is taken and compared to &phi values from associated tracks of 10 other events kept in an array.

**&Delta&phi Correlations - 48 bins - with errors**
The repetitive peak structure is consistent with the effect of endcap sector boundaries. The peak at zero most likely indicates some double counting in the algorithm.

**&Delta&phi Charged Separated Correlations - 48 bins - with errors**
As a systematic check on the correlations, they are sorted by charge:
TOP LEFT -> ++, TOP RIGHT -> --, BOTTOM LEFT -> +-

**&Delta&phi Correlations - 126 bins - with errors**
Finer binning is used to study the peak further. The excess seems to fall exactly at zero.

**&Delta&phi Charged Separated Correlations - 126 bins - with errors**
As a systematic check on the correlations, they are sorted by charge:
TOP LEFT -> ++, TOP RIGHT -> --, BOTTOM LEFT -> +-

The peak at zero seems to disappear in the +- correlations.