This is a reference manual for algorithms implemented for the Integrated Data Processing Environment for Time Correlation Experiments. All work-flow can be split for main procedures:

• Pre-processing,
• Data processing, and
• Presentation of results,

covered by this note with extensive references to the specific code.

Content

Pre-processing

Pre-processing algorithms consist of four procedures

• Dark run scan

...

• ,
• Pedestals averaging,
• Data scan, and
• Data averaging,

described in this section.

Dark run scan

Defines for Defines for the dark run

• the number of events
• time records and average time interval

...

Pedestals averaging

Defines for the dark run

• pedestals
• RMS
• hot pixel mask

...

The ImgAlgos.ImgMaskEvaluation produces the saturated pixel mask; the image size txt file *-satpix-mask-level-65000ADU.

...

txt, consistiong 0(zero) or 1(one) for each bin.

Data processing

Data processing

...

stage consists of three procedures:

• Spliting,
• Processing, and
• Merging,
  described in this section.

Spliting

Submit command

Split

Submit command

psana -c /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-cora-xcsi0112-r0015-split.cfg /reg/d/ana12/xcs/xcsi0112/xtc/e167-r0015-*.xtc

...

[psana] 
# Command to run this script from release directory: 
# psana -c ImgAlgos/data/psana-split.cfg <path-to-xtc-file-name-pattern-for-one-run> 

#files = /reg/d/ana12/xcs/xcsi0112/xtc/e167-r0015-*.xtc 
skip-events = 0 
events = 500 

modules = ImgAlgos.Tahometer ImgAlgos.PrincetonImageProducer ImgAlgos.ImgCalib ImgAlgos.ImgIntMonCorr ImgAlgos.ImgIntForBins ImgAlgos.ImgVsTimeSplitInFiles ImgAlgos.ImgAverage

[ImgAlgos.Tahometer] 
print_bits = 7 

[ ImgAlgos.PrincetonImageProducer ] 
source = DetInfo(:Princeton) 
key_in = 
key_out = img 
print_bits = 1 

[ImgAlgos.ImgCalib] 
source = DetInfo(:Princeton) 
key_in = img 
key_out = calibrated 
fname_peds = /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-xcsi0112-r0020-peds-ave.txt 
fname_bkgd = 
fname_gain = 
fname_mask = 
fname_rms =  
threshold_nrms = 0 
do_threshold = true 
threshold = 20.0 
below_thre_value = 0 
print_bits = 5 

[ImgAlgos.ImgIntMonCorr] 
source = DetInfo(:Princeton) 
key_in = calibrated 
key_out = imon_corrected 
fname_imon_cfg = /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-cora-xcsi0112-r0015-imon-cfg.txt 
print_bits = 1 

[ImgAlgos.ImgIntForBins] 
source = DetInfo(:Princeton) 
key_in = imon_corrected 
fname_map_bins = /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-cora-r0015-map-static-q.txt 
fname_int_bins = /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-cora-r0015-int-static-q.txt 
number_of_bins = 1 
print_bits = 33 


[ImgAlgos.ImgVsTimeSplitInFiles] 
source = DetInfo(:Princeton) 
key = imon_corrected 
fname_prefix = /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-cora 
file_type = bin 
add_tstamp = false 
ampl_thr = 20.0 
ampl_min = 01 
nfiles_out = 8 
print_bits = 29 


[ImgAlgos.ImgAverage] 
#======EOF====== 
source = DetInfo(:Princeton) 
key = calibrated 
avefile = /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-xcsi0112-r0015-data-ave.txt 
rmsfile = /reg/neh/home1/dubrovin/LCLS/PSANA-V01/work/t1-xcsi0112-r0015-data-rms.txt
#======EOF====== 

PSANA module PSANA module ImgAlgos.ImgCalib

• ImgAlgos.ImgCalib.cpp
• ImgAlgos.ImgCalib.h
  This module is responsible for basic image intensity transformation. For correlation analysis it applys a couple of corrections:
• subtract pedestals and
• apply LLD threshold.

PSANA module ImgAlgos.PSANA module ImgAlgos.ImgIntMonCorr

• ImgAlgos.ImgIntMonCorr.cpp
• ImgAlgos.ImgIntMonCorr.h
  Gets intensity monitor configuration file imon-cfg.txt produced in GUI:

  Code Block
  BldInfo(FEEGasDetEnergy) FEEGasDetEnergy 1 1 1 1 0 0 -1.0000 -1.0000 1.0000 BldInfo(XCS-IPM-02) XCS-IPM-02 1 1 1 1 0 0 -1.0000 -1.0000 1.0000 BldInfo(XCS-IPM-mono) XCS-IPM-mono 1 1 1 1 0 0 -1.0000 -1.0000 -1.0000 DetInfo(XcsBeamline.1:Ipimb.4) Ipimb.4 1 1 1 1 0 0 -1.0000 -1.0000 1.0000 DetInfo(XcsBeamline.1:Ipimb.5) Ipimb.5 1 1 1 1 0 0 -1.0000 -1.0000 1.0000

...

Module ImgAlgos.corana

• ImgAlgos.corana.cpp

Module ImgAlgos.CorAnaData

• ImgAlgos.CorAnaData.cpp
• ImgAlgos.CorAnaData.h

Evaluation of correlators:

• ImgAlgos.CorAnaData.cpp
• ImgAlgos.CorAnaData.h

...

ImgAlgos/include/CorAna.h:  typedef float cor_t;

void CorAnaData::evaluateCorTau(unsigned tau) // tau in number of frames between images
{
  m_log << "\nCorAnaData::evaluateCorTau(tau): tau=" << tau;
  std::fill_n(m_sum_gi, m_blk_size, double(0));
  std::fill_n(m_sum_gf, m_blk_size, double(0));
  std::fill_n(m_sum_g2, m_blk_size, double(0));
  std::fill_n(m_sum_st, m_blk_size, unsigned(0));
  std::fill_n(m_cor_gi, m_blk_size, cor_t(0));
  std::fill_n(m_cor_gf, m_blk_size, cor_t(0));
  std::fill_n(m_cor_g2, m_blk_size, cor_t(0));

  for (unsigned ti=0; ti<m_tind_size-tau; ti++) {
       unsigned tf=ti+tau;

       if ( ! (tf<m_tind_size) ) break;
       
       // get the event index in array for time index
       int evi = m_tind_to_evind[ti];
       int evf = m_tind_to_evind[tf];

       // If the event does not exist for specified time index -> skip it in sum
       if(evi<0) continue;
       if(evf<0) continue;

       sumCorTau((unsigned)evi,(unsigned)evf);
  }
}

//----------------
void CorAnaData::sumCorTau(unsigned i, unsigned f) // i and f are the event indexes
{
   data_t* p_i = &m_data[i*m_blk_size];
   data_t* p_f = &m_data[f*m_blk_size];
   double Ii, If;

   for(unsigned pix=0; pix<m_blk_size; pix++) {
     Ii = p_i[pix]; 
     If = p_f[pix]; 
     m_sum_gi[pix] += Ii; 
     m_sum_gf[pix] += If; 
     m_sum_g2[pix] += Ii*If; 
     m_sum_st[pix] ++; 
   }
}

Averaging:

   for(unsigned pix=0; pix<m_blk_size; pix++) {
       if(m_sum_st[pix]<1) continue;
       m_cor_gi[pix] = cor_t( m_sum_gi[pix] / m_sum_st[pix] ); 
       m_cor_gf[pix] = cor_t( m_sum_gf[pix] / m_sum_st[pix] ); 
       m_cor_g2[pix] = cor_t( m_sum_g2[pix] / m_sum_st[pix] ); 
   }

Module ImgAlgos.CorAna

• ImgAlgos.CorAna.cpp
• ImgAlgos.CorAna.h

...

• ImgAlgos.CorAnaMergeFiles.cpp
• ImgAlgos.CorAnaMergeFiles.h

Presentation of results

Presentation of results is implemented in the GUIViewResults.py, which basically is a panel of buttons for different plots.

Summary

In this note we presented a functional description of implemented procedures for time correlation analysis. All modules have convenient reference to the latest version of the code.

References

• Module ImgAlgos.GlobalMethods
• ImgAlgos.GlobalMethods.cpp
• ImgAlgos.GlobalMethods.h

...