Structure of the File

First the SUSY particle and top quark masses and lifetimes are given as, for example:

65
401	927.3980	0.74510E-13
402	925.3307	0.74009E-13
....etc.

That is,

Number of SUSY + top particles
IDHW, RMASS(IDHW), RLTIM(IDHW)
repeated for each particle

IDHW is the HERWIG identity code, the codes for SUSY particles are available here, or from the documentation where the codes for Standard Model Particles can also be found. RMASS and RTLIM are the mass, in GeV, and lifetime, in seconds, respectively.

This is read into HERWIG with the following FORMAT statements.

          READ (LRSUSY,'(I4)') NSSP
          DO I=1,NSSP
               READ (LRSUSY,1) IHW,RMASS(IHW),RLTIM(IHW)
          ENDDO
1        FORMAT(I5,F12.4,E15.5)

Next each particles decay modes together with their branching ratios and matrix element codes are given as, for example:

6
401	0.18842796E-01	0	450	1	0	0	0
401	0.32755006E-02	0	457	2	0	0	0
....etc.
6
402	0.94147678E-02	0	450	2	0	0	0
....etc.

That is,

Number of decay modes for a given particle (IDK)
IDK(*), BRFRAC(*), NME(*) & IDKPRD(1-5,*)
repeated for each mode.

Repeated for each particle.

IDK is the HERWIG code for the decaying particle, BRFRAC is the branching ratio of the decay mode. NME is a code for the matrix element to be used, either from the SUSY elements given below or the main documentation. IDKPRD are the HERWIG identity codes of the decay products.

This is read into HERWIG with the following FORMAT statements.

        DO I=1,NSSP
              READ (LRSUSY,'(I4)') NDEC
              IF (NDEC.GT.0) THEN
                    DO J=1,NDEC
                        NDKYS=NDKYS+1
                        READ (LRSUSY,11) IDK(NDKYS),BRFRAC(NDKYS),NME(NDKYS),
    &                             (IDKPRD(K,NDKYS),K=1,5)
11                   FORMAT(I6,F16.8,6I6)
                    ENDDO
              ENDIF
        ENDDO

The order in which the decay products appear is significant: this is important in order to obtain appropriate showering and hadronization. The correct ordering for each decay mode is indicated here.

Two new matrix element codes have been added for these new decays:

NME =	200	3 body top quark via charged Higgs
	300	3 body R-parity violating gaugino and gluino decays

Next a number of parameters derived from the SUSY Lagrangian must be given. These are:

the ratio of Higgs VEVs, tan(beta)		TANB
the scalar Higgs mixing angle, alpha		ALPHAH
the neutralino mixing matrix N in the notation of Gunion and Haber.		ZMXNSS
the chargino mixing matrix V in the notation of Gunion and Haber.		WMXVSS
the chargino mixing matrix U in the notation of Gunion and Haber.		WMXUSS
Stop mixing angle		THETAT
Sbottom mixing angle		THETAB
Stau mixing angle		THETAL
Stop A term		ATSS
Sbottom A term		ABSS
Stau A term		ALSS
Mu parameter		MUSS

        READ (LRSUSY,'(2F16.8)') TANB,ALPHAH
        DO I=1,4
            READ (LRSUSY,13) ZMXNSS(I,1),ZMXNSS(I,2),ZMXNSS(I,3),ZMXNSS(I,4)
        ENDDO
        READ (LRSUSY,13) WMXVSS(1,1),WMXVSS(1,2), WMXVSS(2,1),WMXVSS(2,2)
        READ (LRSUSY,13) WMXUSS(1,1),WMXUSS(1,2), WMXUSS(2,1),WMXUSS(2,2)
        READ (LRSUSY,'(3F16.8)') THETAT,THETAB,THETAL
        READ (LRSUSY,'(3F16.8)') ATSS,ABSS,ALSS
        READ (LRSUSY,'( F16.8)') MUSS
13   FORMAT(4F16.8)

Finally the logical variable RPARTY should be set: if TRUE then the R-parity violating couplings must also be supplied, otherwise not.

        READ (LRSUSY,'(L5)') RPARTY
        IF(.NOT.RPARTY) THEN
            READ(LRSUSY,20) (((LAMDA1(I,J,K),K=1,3),J=1,3),I=1,3)
            READ(LRSUSY,20) (((LAMDA2(I,J,K),K=1,3),J=1,3),I=1,3)
            READ(LRSUSY,20) (((LAMDA3(I,J,K),K=1,3),J=1,3),I=1,3)
        ENDIF
20   FORMAT(27E16.8)

The R-parity violating superpotential we used is given in the preprint OUTP-99-26P.