From Hall A Wiki
Revision as of 13:34, 25 February 2015 by Cohen
SIMC repository and documentation
- 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
- create an input file under the directory infiles following the repository examples, e.g.
- 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")