Sim geant3

From solidwiki
Jump to: navigation, search

for record keeping only, don't use it!

At the proposal stage, Eugene Chudakov developed the solid simulation based on comgeant

Some of the design for PVDIS by Eugene Chudakov are

detail implementation

comgeant user guide has geometry and material definition.

Further refer to the "GEOM050 The GEANT shapes" in geant3 guide

Eugene Chudakov for PVDIS is at his personal computer

Xin Qian for SIDIS He3 at /work/halla/e03004/disk1/xin/12gev/TRANSVERSITY/

Kalyan Allada and Chao Peng for SIDID NH3 at /work/halla/solid/kalyan/solid_g3sim

They are backed up on tape at /mss/halla/solid/sim/geant3

There two kind of backup, one has soft links, the other "nolink" replace links with hard copy, refer to dereference

   configuration at solid_comgeant_pvdis/pvdis_02_01_p_14_01
     fort.15 - initiates reading the other files
     fort.17 - materials/media
     fort.21 - basic geometry
     fort.22 - additions (baffles)
  • SIDIS He3
   BaBar: TRANSVERSITY/sim_summary/BABAR (used for PAC34 proposal, scintillator and MRPC were not in)
   CDF:   TRANSVERSITY/sim_summary/CDF   (used for PAC35 proposal update, scintillator and MRPC were added, and other configiration change))
   BaBar: TRANSVERSITY/sol_transv_largeangle_new (similar to CDF version with new configuration)
     the geometry and materials are in the files
     fort.15 - initiates reading the other files
     fort.21 - basic geometry, materials/media
     fort.16 - additions

How to run it (with transversity configuration)

1. get files from tape and extract them
2. run ./comg_inter.rhws3u.exe
3. run "exec plot_setup_new.kumac" to see the geometry
4. running the simulation, like "trig 10000"
5. you can open the nt like "hi/file 1 csimout.nt"
6. you can then do "nt/plot //LUN1/2.hitraxy.f(....)"
7. decode the information from the reuslt nt files /work/halla/e03004/disk1/xin/12gev/TRANSVERSITY/1stnt/extract_info

hit processing

reply from Eugene

On Wed, 25 May 2011, Zhiwen Zhao wrote:

> Hi, Eugene
> In comgeant, for a Hodoscopy with type "HOD1IDTYPE     41", will it detect charge and neutral particles?
the types of hodoscopes are described at

41 - as a MWPC. Records the ionization energy in the active
material. The scaling factors for recording the energy deposit is
different from the MWPC to accomodate larger deposits in plastic in
comparison with gases. (because geant3 record deposit in integer which has a range, so the scale factor is adapted)

42 - a "special" detector for testing purposes. Hits from all
particles (including neutrals) are stored with the amplitude equal to
the particle momentum. For this detector one should declare the
sensitive medium an absorber (see MEDABSORB...)

For calorimeters one can use the types 46-50 (see the WWW page) 
> and what do "HOD1GATE       50." and "HOD1THRES       0" really mean?
The GATE in ns the time window to digitize the hits. It is useful if
the pileup is turned on. Also, there are cases of slow charged
particles trapped in the magnetic fields, which may produce delayed
signals. Neutrons can also produce delayed signals.  The time of the
hit "t" is calculated with respect to the TOF of a photon reaching the
given detector from the "zero time point" XYZTIME0.  The condition:

THRES is the threshold for the digitization. Zero means that any
positive energy deposit will produce a digitization.
> thanks
> Zhiwen