Difference between revisions of "Using SIMC"

Revision as of 14:33, 25 February 2015

SIMC repository and documentation

• [SIMC short documentation]

• SIMC on github

Brief Overview

• SIMC main inputs are

 Beam energy , Spectrometers angles , Determination of which spectrometer detects electrons and which detects hadrons , 
 Target parameters (A,Z,density etc.) , Generator acceptance and resolution

• The generator will generate events with the reaction 4 physical variables

 in-plane angle y' , out-of-plane angle x' , y(target) , momentum difference from central spectrometer momentum - delta

• COSY simulation tool will generate the hrs_cosy file which include the transportation parameters for the particle along the spectrometer

• The output of the simulation would be the 4 physical variables reconstructed at the focal plane of each spectrometer

How to run SIMC

• compile SIMC directory: go to the SIMC directory, change what ever necessary in Makefile and type

 make

• create an input file under the directory infiles following the repository examples, e.g.

 infiles/hrsr_eep_h.inp

• execute SIMC with an input file, e.g.

 simc 
 (enter input file)> hrsr_eep_h

• after the run was completed 4 output files are generated

 outfiles/hrsr_eep_h.geni  (information)
 outfiles/hrsr_eep_h.hist   (run settings)
 outfiles/hrsr_eep_h.gen   (output text file)
 worksim/hrsr_eep_h.rzdat   (paw ntuple)

• convert the paw file into root

 cd worksim/
 h2root hrsr_eep_h.rzdat 

• a root file hrsr_eep_h.root will now be generated in /worksim/.

• The tree is called h666, and the most important variables are the reconstructed 4 variables (hs-electron arm, ss-hadron arm) and those generates (add an i), e.g.

 hsdelta ,  hsdeltai  ,hsytar ,  hsytari  ,hsyptar ,  hsyptari  , hsxptar ,  hsxptari

• To draw, e.g. the difference between the generated and reconstructed momentum, use

 h666 -> Draw("hsdelta - hsdeltai")