Instruction on running spin_rot simulation

geant4/spin_rot/run/readme_spin_rot.txt

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+How to carry out a simulation with the spin rotator suite sr1:
+
+1. Export the original Opera magnetic field maps (first octant) to an 
+   extended field map (all octants), suitable for use with Geant4.
+   - Launch Matlab and then run field_import.
+   - Use help field_import for usage hints.
+
+2. Copy the extended field map in the directory spin_rot/run
+
+3. If needed, edit one of the 11xx.mac files and change the line:
+   ... 2DE  L1_Erz.map  log_L1ENV  8. 
+   so that the L1 voltage coincides with the file name (e.g. 8 is 1108.mac).
+   
+   Check also that you are using the correct magnetic field map (line above):
+   ... 3DB  sep_1nl_ext.map  log_BField  0.0312
+   Run it once with: sr1 1108.mac > data/1108.txt and, if everything is 
+   correct, proceed to the next step.
+   
+4. Save the current macro and make as many copies of it as are the L1 
+   voltages to explore. Edit each of them (e.g. with vim) and modify 
+   the L1ENV  8 line to coincide with the respective file name.
+   
+5. Run a BATCH simulation using the command (edit if necessary):
+   run_jobs &
+   Do not forget to issue the g49 command BEFORE launching the job.
+
+6. Check the simulation progress by using: ls -trl data.
+   NOTE: To stop a running job, bring it to foreground first with 
+   e.g. fg run_jobs and then stop it by Ctrl+C (or kill %1).
+   To suspend a job temporarily just type Ctrl+Z (refer to ref_card).
+   
+7. Analyse the generated root and txt files. If only the total number 
+   of events is needed, then use the sr_transm.C script inside root:
+   
+   - Enter root with: root -l
+   - Load the script with: .L sr_transm.C
+   - Execute the script:   sr_transm("data/sr1_1108.root")
+   - Quit root using:      .q
+   
+8. The root script generates both a screen output as well as an .eps file.
+   One can view it with, e.g.: gv data/sr_bspot_8.eps, get the needed 
+   information from the statistics and copy the Entries value by hand in 
+   the final matlab file (sr_transm_L1.m).
+   For a batch processing use the following fast grep command:
+   less data/sr_bspot_*.eps | grep bspot_histEntries
+
+9. If not needed, clear the root, txt and eps simulation data:
+   rm data/sr1_11*.root, etc.
+
+