November 2011 ntuple structure

• For each run, there are 2 ntuples: pedestal_runXXXX.root (containing pedestal data) and datafile_runXXXX.root (containting physics data)
• the latest ntuples can be found on pcdream.cern.ch in the folder: /mnt/wd/working_bak/ntuple/
• some example macro to read DRS data can be found here -
• Channel mapping has changed during the test beam. You can find the mapping here: ROmappingNovember2011 (or REFER TO THE LOGBOOK FOR CHANNEL MAPPING a scan of the logbook is available DreamDataAnalysis if you have)
• Depending on the run setup, the ADCs cabling may change. A scheme of the readout is on WebHome.

Notes for the analysers

Ntuple structure is basically the same as July 2011, the only difference is that DATADRS is now an array of UShort_t instead of an array of Float_t and that to the number of ADC counts is multiplied by 16. To get the number of ADC count in one sample of DRS dato you have to take DATADRS[group][channel][sample]/16. This modification was implemented to reduce the filesize.

There has been a big improvement with respect to the 2009 ntuples: now channels are stored in the arrays in the correct order so that (for instance) CHARGEADCN0[6] always contains the charge of the 6th channel of ADC0 and you do not need to check CHADCN0[6]. The variable CHADCN0[] is still there so you old macro will keep working, but you can write your new macro without using it.

Ntuple structure scheme

Data types:

• I : a 32 bit signed integer (Int_t)
• i : a 32 bit unsigned integer (UInt_t)
• F : a 32 bit floating point (Float_t)
• B : a 8 bit signed integer (Char_t)
• s : a 16 bit unsigned integer (UShort_t)
• S : a 16 bit signed integer (Short_t)
• b : a 8 bit unsigned integer (UChar_t)

-- MicheleCascella - 29-Oct-2011