titles_mpca


                   Titles: MPCA: Multiphoton PCA walk correction
                 ==================================================
 
    Contact:  C. Kyba, Penn
 
    Revision History:-
    ================
 
    5.00  C. Kyba              First version.
    5.01  C. Kyba              Add MC banks

 
Titles Files
------------
 
mpca_data.dat
 
 
Verification
------------
 
 
Description
-----------
 
    This bank contains data for applying the multiphoton PCA correction.
    The data is binned in non-equal width bins.  The gain scaled charge is 
    the central charge of the bin, the time (in ns) holds the offset that
    should be subtracted from pt0 in order to generate the multiphoton time.

    Bank 1 contains the correction data for data
    Bank 2 contains the correction data for MC with the obsolete charge dist
    Bank 3 contains the correction data for MC with the new charge distribution

 
Data Words
----------
 
        Data types: B(bit), I, F, D(double), H(hollerith 4 char)

 Word  Type  Mnemonic               [symbolic command]  Description
 ----  ----  --------               -------------------------------
    1  I     KMPCA_NUM_POINTS       Data points  Number of data points in the file
 2..5  I                            Spare
 6..10 F                            Spare
11..N  F                            There are five entries in the titles
                                    file for each data point, see the note
                                    below

Notes
-----
1)  The data is stored as a repeating table of floating point numbers.  The
    first word of actual data is located at (KMPCA_STATUS_WORDS+1).  Mnemonics
    have been set up to assist in reading the data.  Assume that you are
    looking the i'th charge bin.  The data is then stored in words:

KMPCA_STATUS_WORDS+(i*5)+...

  +1  F     KMPCA_CHARGE           Bin centroid charge (pe)
  +2  F     KMPCA_TIME             MPCA time shift (ns)
  +3  F     KMPCA_SIGMA            RMS of calibration times (ns) SEE NOTE 2 BELOW
  +4  F     KMPCA_SDOM             Standard Deviation of the Mean of calibration times (ns)
  +5  F     KMPCA_NUM_HITS         Number of hit tubes in this charge bin

2)  As of version 5_0082 the RMS returned by CAL is actually a fit to the data 
    in bank 1.  The MC MPCA times are smeared in order to make their first
    photon time spread look like the data.  The RMS returned by cal is now
    expected to be a reasonable match to the data, although it is highly
    recommended that this be studied with muon data.



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