Common Blocks, Block Data and Parameters

No input files are required by the generator. The leptoquark S is the default type and all parameters are given sensible default values. The generator makes use of the external common blocks /LUJETS/, /HEPEVT/, /LUDAT2/, /LUDAT4/, /QUADRE/ and /PRINT/. There is one internal common block /LQCOMM/ containing variables, and one parameter file LQPARM containing compile-time parameters. The internal common block values have the following meaning and default values are shown as (D=...). Only variables with a default value may be changed by the user.

 
   		  		 IPROC, TWOTIMEST3, IDECAY, IDECGEN,
                                     MEVENT

& ,                           		 PARTSH, ECMS, MLQ, QLQ, T3LQ, GL,
                                     GR, LAML, LAMR

 
IPROC:      		 (D=0) Leptoquark type: 		    ,

            		                        		    ,

            		                        		    ,

            		                        		    ,

            		                        		    ,

            		                        		    ,

            		                        		    ,

            		                        		    ,

            		                        		     or

            		                        		    .

TWOTIMEST3: 		 (D=0)   , where    is the third component
               of the weak isospin of

            		 the leptoquark.

IDECAY:     		 (D=0) Decay type: 		 0 = l  l   + 2 jets,

            		                   		 1 = l,   + 2 jets or

            		                   		 2 =   ,   + 2
                                        jets.

IDECGEN:    		 (D=0) Decay generation: 		 0 = 1'st generation,

            		                         		 1 = 2'nd generation or

            		                         		 2 = 3'rd generation.

MEVENT:     		 (D=0) Number of events to generate.

ECMS:       		 (D=140.0) Centre-of-mass energy,    (GeV).

MLQ:        		 (D=40.0) Leptoquark mass,    (GeV/c  ).

QLQ:        		 (D=1/3) Electromagnetic charge of the leptoquark,
                 .

T3LQ:       		 (D=0) Third component of the weak isospin of the
               leptoquark,   .

GL, GR:     		 (D=0.0,0.0) Generalized left-handed and right-handed
               coupling

            		 strengths (= 0.3 is the electromagnetic
               coupling strength;

            		 ie.   ).

LAML, LAMR: 		 (D=0.0,0.0) Left-handed and right-handed coupling
               strength to

            		 lepton-quark pairs.

PARTSH:     		 (D=0) parton showers: 		 0 = no parton showers or

            		                       		 1 = final state parton showers
                                            using

            		                       		 LUSHOW.

Variables IPROC, TOWTIMEST3, IDECAY, IDECGEN, ECMS, MLQ, GL, GR and PARTSH may be set by the user or the defaults used. Variable MEVENT should be updated by the user after each event is generated. The above parameters are given default values by loading the block data subprogram LQDATA. Parameters QLQ, T3LQ, LAML and LAMR are calculated at initialization by subroutine LQINIT.

File LQPARM: UNITS, PI, ALPHA, SIN2W, MZ, GZ

At the moment this is not a true common block but rather an include-file with parameter statements. Thus the default values many not be modified at run-time by the code.