C CONSTS                 BASIC CONSTANTS
C
C PI                   3.1415926535898
C RADIAN               NUMBER OF DEGREES IN A RADIAN
C CLIGHT               VELOCITY OF LIGHT (GIGAVOLTS/C PER KILOGAUSS)
C EMASS                MASS OF AN ELECTRON (GEV ENERGY EQUIVALENT)
C
      COMMON /CONSTS/ PI, RADIAN, CLIGHT, EMASS