4.3.3.3 Track position

      REAL
     .     VERT(3,MAXTRK),      ! True production vertex position of
                                ! particle
     .     IPRF(MAXTRK,2),      ! True and Seen impact parameter in Rphi.
                                ! True value has geometric sign; seen
                                ! value (calculated by a call to
                                ! ZAUCIP) can have geometric or
                                ! life-time sign, depending on how
                                ! ZAUCIP was called.
     .     IPZ(MAXTRK,2),       ! True and seen impact parameter in z. Ditto
     .     EIPRF(MAXTRK),       ! Seen error on impact parameter in Rphi.
                                ! Calculated by ZAUCIP
     .     EIPZ(MAXTRK),        ! Seen error on impact parameter in z. Ditto.
     .     PAR(5,MAXTRK),       ! Seen track parameters at perigee:
                                !   Par(1)   = Impact-parameter in Rphi,
                                !              with geometric sign
                                !   Par(2)   = Impact-parameter in Z
                                !   Par(3)   = theta
                                !   Par(4)   = phi at perigee
                                !   Par(5)   = 1/Radius of curvature
                                ! PAR is identically zero for particles
                                ! only seen by calorimeters.
     .     WGT(15,MAXTRK),      ! Seen weight matrix of track parameters
                                ! at perigee, in packed form ,ie.
                                ! the elements of WGT are in the
                                ! following positions in the symmetric
                                ! 5X5 weight-matrix :
                                !
                                !     1   2  4  7 11
                                !     2   3  5  8 12
                                !     4   5  6  9 13
                                !     7   8  9 10 14
                                !     11 12 13 14 15
                                !
                                ! WGT is identically zero for particles
                                ! only seen by calorimeters.
     .     HITBAR(25,MAXTRK),   ! bitted word telling what detector
     .     HITFWD(25,MAXTRK)    ! layers measured the track parameters:
                                !  if barrel layer i was hit, bit i is
                                ! set in HITBAR, and if forward layer
                                ! i was set, the bit is set in HITFWD.
                                ! Use the bit-handling routines in
                                ! the utilities patch GENUTL !
                                ! Use the access-routines in SGVTRKER
                                ! to find out more information on the
                                ! layer. Eg. ZTCNAM(IGEO,layer#,'TRACK')
                                ! gives the user-assigned name of a barrel
                                ! layer
      LOGICAL
     .     INVTX(MAXTRK),       ! the track is in the fitted main vertex
                                ! (if ZAUVF1 was called)
                                !
                                ! (RFFAIL, IJETVX and INSV bellow are not
                                ! set by SGV; they are included for user
                                ! convenience. However, SGV resets them
                                ! to FALSE at the beginning of each event.)
     .     RFFAIL(MAXTRK),      ! refit failed for the track
     .     IJETVX(MAXTRK,MAXJET,4), ! the track is in a sec. vertex in the jet
     .     INSV(MAXTRK,MAXJET)  ! the track is in a sec. vertex.