Simple PMT Waveform Analysis

This page describes how to access simple TTrees which contain raw PMT information.

Two trees are stored, one saving waveforms and information for each PMT, the other saving a sum of the waveform from all 32 PMTs.

Waveform-by-wavefoorm TTree:

root [5] wf_1_tree->Show(0)
======> EVENT:0
 run             = 19123
 subrun          = 0
 event           = 1
 ettime          = 1.53789e+09
 ch              = 0
 t_wrt_trigger   = 0.40625
 ped_median      = 2051
 ped_mean        = 2050.27
 ped_rms         = -5
 max_adc         = 2052
 min_adc         = 2049
 wf              = (vector<short>*)0x3f98010

Average waveform TTree:

root [6] wfsum_1_tree->Show(0)
======> EVENT:0
 run             = 7498
 subrun          = 171
 event           = 8551
 ettime          = 1.47292e+09
 wf_sum          = (vector<int>*)0x20a32f0
 wf_max          = (vector<int>*)0x20c4b50

The wf_sum vector is a 1,500 sample waveform, as shown below, of EXT-BNB triggered events. These events are required to have some light activity in the time-tick range between 194 and 306 time-ticks. The wf_max vector contains 32 entries, one per PMT, and stored the maximum ADC for a given PMT in the event.