Difference between revisions of "CTOF Delta T"

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(Created page with "== Delta T of CTOF hits== In this section we look at the time difference of hits in the same paddle between the top and the bottom PMT. Two sources of timing information are...")
 
(Delta T of CTOF hits)
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== Delta T of CTOF hits==
 
== Delta T of CTOF hits==
  
In this section we look at the time difference of hits in the same paddle between the top and the bottom PMT. Two sources of timing information are used, the time from the ADC itself and the time from the TDC. The DANA objects used here are DCTOFHit objects that have the following structure:
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In this section we look at the time difference of hits in the same paddle between the top and the bottom PMT. Two sources of timing information are used, the time from the ADC itself and the time from the TDC. The DANA objects used here are DCTOFHit objects with the container class having the following structure:
  
 
  int bar; ///< bar number
 
  int bar; ///< bar number
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  double t; ///< time in ns
 
  double t; ///< time in ns
 
  double t_adc;///< time in ns from FADC
 
  double t_adc;///< time in ns from FADC
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Note that the factory that fills this structure already applies timing corrections like offsets to the timing data t and t_adc. We select data that have a CTOF trigger only meaning no other trigger bits are set. To provide an understanding as to how often it happens that in addition to the CTOF trigger another trigger bit is set either on the front pannel (LED trigger, random) or in the GTP (physics trigger, PS trigger) the following plot can be studied:
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[[File:ctof_triggers.gif| 200px]]

Revision as of 09:29, 7 December 2022

Delta T of CTOF hits

In this section we look at the time difference of hits in the same paddle between the top and the bottom PMT. Two sources of timing information are used, the time from the ADC itself and the time from the TDC. The DANA objects used here are DCTOFHit objects with the container class having the following structure:

int bar; ///< bar number
int end; ///< top=0,bottom=1;
float dE; ///< attenuated energy deposition in GeV
double t; ///< time in ns
double t_adc;///< time in ns from FADC

Note that the factory that fills this structure already applies timing corrections like offsets to the timing data t and t_adc. We select data that have a CTOF trigger only meaning no other trigger bits are set. To provide an understanding as to how often it happens that in addition to the CTOF trigger another trigger bit is set either on the front pannel (LED trigger, random) or in the GTP (physics trigger, PS trigger) the following plot can be studied:

Ctof triggers.gif