Vertical Magnetic Field in the Back Leg Hole -0.668 0.693 /elhin, elhout (meters) elhin, elhout were some reference points used by incoming tracking program. I don't remember how they were used exactly, but the negative field in the hole did go through zero and reverse sign very close to the hole's emergence from the back leg steel. From there on, the fringing main field can be derived from the file g2RING.map Column 1: distance in meters along hole axis from some central point Column 2: By/By0 (By0= -0.02883 Tesla at center of hole) -1.075 0. -1.030 0. /upstream end -0.985926 0.024280 -0.941256 0.050488 -0.896597 0.077851 -0.851928 0.108683 -0.807248 0.159171 -0.762589 0.237792 -0.717920 0.354954 -0.673260 0.489074 -0.628591 0.642464 -0.583921 0.867152 -0.539262 0.992408 -0.494583 1.031333 -0.449923 1.029021 -0.405254 1.014761 -0.360595 1.008595 -0.315925 1.005511 -0.271256 1.004740 -0.226597 1.002813 -0.181917 1.002043 -0.137258 1.000116 -0.092588 1.000116 -0.047929 0.999730 -0.003260 1.000116 0.041400 1.001272 0.086069 1.003584 0.130748 1.007438 0.175408 1.011292 0.220077 1.017073 0.264737 1.023240 0.309406 1.028250 0.354075 1.035958 0.398735 1.048676 0.443414 1.069873 0.488073 1.086831 0.532743 1.059853 0.577412 0.975835 0.622071 0.781208 0.666741 0.586580 0.711400 0.447451 0.756080 0.325278 0.800739 0.211971 0.845408 0.119860 0.890068 0.069758 0.934737 0.035071 0.979396 0. /downstream end 1.024066 0.