After the installation procedure, an executable module of JIM is located under bin directory. There is a simple template shell script, run_jim, under jim/srcdirectory.
In order to execute the JIM module, some FFREAD input cards, which control the behavior of the JIM, from standard input are necessary.
Some data cards are already defined by GEANT. The followings are some typical cards which can be very useful for users.
| KEY | N | Type | Short description | Default value |
|---|---|---|---|---|
| TRIG | 1 | I | Total number of events to process | 10000000 |
| RNDM | 2 | I | Initial random number seed (2 words) | 0 0 |
| DEBU | 3 | I | First and last event# to debug and print control frequency | 0 0 0 |
| SWIT | 1 | I | User flags for debug | all 0 |
Some data cards are already defined by GEANT. The followings are some typical cards which can be very useful for users.
| KEY | N | Type | Short description | Default value |
|---|---|---|---|---|
| SKIP | 1 | I | Number of events to be skipped from input source | 0 |
| GTYP | 1 | I | Switch to control geometry type. 1 for 2-Tesla version and 2 for 3-Tesla version. | 1 |
| MFLD | 1 | R | Strength of the overall magnetic field in kGauss | depends on the value of GTYP |
| BMAP | 1 | C | If set as 'ON', detailed magnetic field map is used around the interaction region | Blank |
| HIST | 1 | I | Flag for the standard histogarming | 0 |
| KEY | N | Type | Short description | Default value |
|---|---|---|---|---|
| EVTO | 1 | C | Output file name for events generated by "JIM" | Blank |
| HBK | 1 | C | Histogram output file name | Blank |
| PS | 1 | C | Postscript output file name, when some graphics are displayed | Blank |
| KEY | N | Type | Short description | Default value |
|---|---|---|---|---|
| DRAW | 1 | C | Parameter input file name for graphic display | Blank |
| JB | 1 | C | Parameter input file name for background study | Blank |
| KEY | N | Type | Short description | Default value |
|---|---|---|---|---|
| VX | 1 | C | Geoetry parameter file name for vertex detector | Blank |
| CT | 1 | C | Geoetry parameter file name for central tracker | Blank |
| BC | 1 | C | Geoetry parameter file name for barrel calorimeter | Blank |
| EC | 1 | C | Geoetry parameter file name for end-cap calorimeter | Blank |
| MU | 1 | C | Geoetry parameter file name for muon detector | Blank |
| IR | 1 | C | Geoetry parameter file name for interaction region | Blank |
| BM | 1 | C | Geoetry parameter file name for beam monitor | Blank |
| LM | 1 | C | Geoetry parameter file name for luminosity monitor | Blank |
| IT | 1 | C | Geoetry parameter file name for intermediate tracker | Blank |
Detailed explanation of contents of parameter files
| KEY | N | Type | Short description | Default value |
|---|---|---|---|---|
| GEN | 1 | C | Input souce for JIM | Blank |
| GENP | 10 | R | Parameters for the input source | Blank |
| VECI | 1 | C | Four-vector input file name in case GEN cards pecifies FILE input | 0. |
JIM can accept various kind of input 4-vectors as its input. User can select input source by the GEN data card as:
GEN 'source'
Possible input sources are described below:
Generates e+e- -> hadrons with the JETSET74 generator of CERNLIB. CMS energy is given by the first parameter of GENP data card.
GEN 'LUND'
GENP 250.
gives hadronic events at ECM=250 GeV.
Generates top quark pair productions with the JETSET74 generator. CMS energy is also given by the first parameter of GENP data card. Default mass of the top quark is set as 174 GeV, which can be changed by the second parameter of GENP CARD.
GEN 'TOP'
GENP 500. 175.
gives top quark pair events at ECM=500 GeV with
mtop=175 GeV.
Generates Higgs events by PYTHIA (MSEL =16). CMS energy is given by the first parameter of GENP data card. Default mass of the Higgs particle is set to 120 GeV, which can be changed by the second parameter of GENP CARD.
GEN 'HIGGS'
GENP 250. 130.
gives top quark pair events at ECM=250 GeV with
mHiggs=130 GeV.
Generates a single particle for debugging use. The first parameter of GENP data card gives momentum of generated particles. If it is given in negative value, it gives their transverse momentum. The second parameter gives their JETSET particle code.
If |CODE|<1000, particles are generated to the fixed direction, which is given by the third (theta in degree) and fourth (phi in degree) parameters. If |CODE|>1000, then particles are uniformly generated in the central region which is limited by a veto angle, the third parameter (in degree).
GEN 'SINGLE'
GENP 10. 11. 45. 180.
gives electrons with 10 GeV generated into theta=45 degrees and
phi=180 degrees.
GEN 'SINGLE'
GENP 5. -1013. 60.
gives positive muons with 5 GeV generated uniformly in the
central region from 60 to 120 degrees.
Generates multi particles for debugging use. The following list shows the possible GENP parameters:
Read 4-vectors form a file given by VECI data card.
In order to speed up execution time, some of calorimetric detectors have smearing mode in "JIM". This mode can be given by SIMD data card. If user wants to use smearing mode for a certain detector components, value "1" should be given to the corresponding detector number.
At present the following detectors have smearing mode:
SIMD 3=1 4=1 11=1 12=1