BEAM X Y Z dX dY dZ Lum NMB (Beam position and spread, luminosity, Flag, NMB) DTBX DTBX chamber reconstruction control parameters REVF Vertex fit control parametersThe BEAM card defines the nominal pp beam position and spread at the interaction point (cm units) as well as the luminosity in units of 10
/cm 
/s. The
default values are (missing BEAM card) X=Y=Z=0 and
, dZ=5.3 cm and Lum=1.0. The last parameter
is optional and can be used to fix the number of MB events per bunch
(see section 1.4.5).
The meaning of the cards DTBX and REVF is explained in the muon and tracker sections of Reference Manual, respectively.
Listed below is an example of control cards.
LIST
C Nominal collision point and sigmas (cm) Lumi/10**34 N-pile
BEAM 0. 0. 0. 0.0010 0.0010 5.3 0.1 0
C *.ntpl no use etamin etamax fimin fimax ptmin ptmax HEPEVT-fl
KINE 0 0. -2.4 2.4 0. 360. 1. 9999. 1.
TIME 5. 5. 1
RUNG 1 1 (User run and first event number)
GEOM 'CMSE' 3 'ECAL' 1 'HCAL' 1 (Geometry options)
SETS 'CMSE' 1 'ECAL' 0 'HCAL' 0 (HITS activation-deactivation)
CFIL 'HBKO' 'cms113.hbook ' (Hbook output file)
'META' 'geant.ps ' (Graphics output file)
'EVTO' '$SCRATCH/minbias.fz ' (Events output file)
SAVE 'HEAD' 'HITS' 'KINE' 'VERT' (Output structures selection)
PILE 'CMSE' -1 (Pile-up control)
DIGI 'CMSE' 0 (Digitisation control)
RHIT 'CMSE' 0 (Hits reconstruction control)
DBUG 'CMSE' 1 'TRAK' 1123 (specific debug levels)
DEBU -1 100 1 (first,last,frequency to debug)
PRIN 'KINE' (Structures printing)
HBOOK 'TRAK' 1
SWIT 0 3 0 0 6*0 (To see charged & neutrals)
STOP
END
Notice that the HEPEVT flag 1. on KINE card implies that the HEPEVT common
is stored in VERT user words (see subsection 1.4.2).
Notice also that if N-pile on BEAM card is a positive number (NMB) a fixed number (=NMB) of MB events is piled up for each bunch-bunch. Otherwise, as in the above example, the program generates a random number NMB from Poisson distribution with mean computed for the given luminosity.