Drift shell tracing code Chris Paranicas and Andrew Cheng JHU/Applied Physics Laboratory, 8/96 For Galileo ephemeris, we appreciate the help of Nat Bachman, Robin Gary, Tom Garrard, and Neil Murphy. I. Output. Output file contains time, position of Galileo (r, lat, east long), L shell calculated, K used to calculate L, B of s/c calculated with model field, and B min on field line calculated with model field. We scale lengths to 1 RJ = 71492 km. II. Calculated Parameters. 1) The L value of the s/c in the particular field model for charged particles with constant K. L is calculated following the method outlined in JGR, 99, 19433, 1994 by Paranicas and Cheng, where, L=2*pi*DM/abs(phi). For any field model, this formula requires a scaling, DM, which we take to be a nominal dipole moment. Phi is the third adiabatic invariant equal to the magnetic flux enclosed by the particle drift shell. We do not include a current sheet at the moment. 2) The value of the second adiabatic invariant, K, in the units sqrt(G)-RJ. This is the K that was used to trace the drift shell and is assumed to be constant on the drift shell. 3) B at the location of the s/c in Gauss as calculated by the particular magnetic field model. 4) The minimum-B (in G) on the field line the spacecraft occupies in the particular magnetic field model. III. Testing drift shell tracing code. To test the code, we calculate the following: LDC = L(OTD model) = L value using tracing code and an offset, tilted dipole model for the field. LDF = L(Dipole formula) = L value using a formula relating position to L shell in an offset, tilted dipole field. For 80 equally-spaced-in-time locations of Galileo between Dec 7, 1995 14:00 - Dec, 8, 1995 05:00, and Bm=0.25 G, we found, Max (LDC/LDF) = 1.0015 and for these 80 points, (1/80) * sum (LDC - LDF)^2 = 3.4e-04 _____________________________________________________________________________ Produced on 4-8-97 Output of tracing code. We calculate the quantities: K, L, B of s/c, and Bmin on s/c field line, using: GSFC O6 model with normalization for L, DM = 4.28 G-RJ^3 This file contains: ihr,imn,isc,r(RJ),lat(deg),east long(deg),L K(sqrt(G)-RJ),B s/c in G, B min in G Time is measured from Jun 26, 1996 00:00:00 Position is Jovian geographic coordinates calculated from the JPL SPICE kernel with input files: gll00007.tpc, gll00007.tls, and s960728a.bsp Other inputs to tracing code are: ipl,sn,rf,dh1,deps,dhs,depss,bm 1 2 1.0 1.00000E-02 1.00000E-03 3.00000E-02 .1 1.00000E-02 Questions contact Chris Paranicas, APL 301-953-5000 x8652 22 0 0 18.23332 -1.65818 115.0721 18.2419 2.75234 7.15011E-04 6.93625E-04 22 10 0 18.16695 -1.63009 109.3147 18.15272 2.72827 7.19493E-04 7.03862E-04 22 20 0 18.10067 -1.60174 103.5593 18.06903 2.70458 7.24257E-04 7.13841E-04 22 30 0 18.03447 -1.57315 97.80612 17.98589 2.68338 7.29411E-04 7.23386E-04 22 40 0 17.96837 -1.54431 92.05503 17.91731 2.66348 7.35053E-04 7.32353E-04 22 50 0 17.90236 -1.51521 86.30609 17.85528 2.64571 7.41263E-04 7.40621E-04 23 0 0 17.83645 -1.48586 80.55934 17.7956 2.62971 7.48110E-04 7.48106E-04 23 10 0 17.77063 -1.45624 74.8148 17.74006 2.61533 7.55641E-04 7.54760E-04 23 20 0 17.70492 -1.42637 69.07248 17.69074 2.6023 7.63882E-04 7.60568E-04 23 30 0 17.63931 -1.39623 63.33241 17.6593 2.59292 7.72844E-04 7.65558E-04 23 40 0 17.57381 -1.36583 57.59461 17.62349 2.58423 7.82515E-04 7.69790E-04 23 50 0 17.50841 -1.33515 51.85911 17.58973 2.57361 7.92866E-04 7.73358E-04 24 0 0 17.44314 -1.30421 46.12591 17.57244 2.57068 8.03854E-04 7.76387E-04 24 10 0 17.37797 -1.273 40.39505 17.55515 2.56534 8.15420E-04 7.79019E-04 24 20 0 17.31292 -1.24151 34.66655 17.53974 2.56052 8.27492E-04 7.81424E-04 24 30 0 17.24799 -1.20975 28.94043 17.52156 2.55582 8.39993E-04 7.83785E-04 24 40 0 17.18319 -1.1777 23.21671 17.49567 2.55077 8.52837E-04 7.86292E-04 24 50 0 17.11851 -1.14538 17.49542 17.47793 2.54503 8.65931E-04 7.89140E-04 25 0 0 17.05396 -1.11277 11.77658 17.4549 2.53853 8.79186E-04 7.92533E-04 25 10 0 16.98954 -1.07988 6.06021 17.42335 2.53049 8.92509E-04 7.96650E-04 25 20 0 16.92526 -1.0467 .3463371 17.39024 2.52051 9.05809E-04 8.01685E-04 25 30 0 16.86112 -1.01323 354.6349 17.34744 2.50899 9.19004E-04 8.07810E-04 25 40 0 16.79711 -.979472 348.9261 17.29811 2.49496 9.32015E-04 8.15185E-04 25 50 0 16.73325 -.945418 343.2199 17.23561 2.47861 9.44774E-04 8.23941E-04 26 0 0 16.66954 -.911069 337.5162 17.1646 2.45958 9.57222E-04 8.34187E-04 26 10 0 16.60598 -.876422 331.8152 17.0839 2.43818 9.69315E-04 8.46013E-04 26 20 0 16.54258 -.841475 326.1167 16.99358 2.41419 9.81025E-04 8.59469E-04 26 30 0 16.47933 -.806227 320.421 16.8973 2.38758 9.92340E-04 8.74569E-04 26 40 0 16.41624 -.770675 314.7279 16.79167 2.35942 1.00327E-03 8.91277E-04 26 50 0 16.35332 -.734817 309.0376 16.68 2.32919 1.01385E-03 9.09515E-04 27 0 0 16.29056 -.698651 303.35 16.56184 2.29746 1.02413E-03 9.29148E-04 27 10 0 16.22797 -.662176 297.6651 16.4387 2.26482 1.03420E-03 9.49983E-04 27 20 0 16.16556 -.625389 291.983 16.31674 2.23176 1.04415E-03 9.71775E-04 27 30 0 16.10333 -.588288 286.3038 16.19458 2.1987 1.05412E-03 9.94218E-04 27 40 0 16.04128 -.550872 280.6274 16.07008 2.16604 1.06424E-03 1.01696E-03 27 50 0 15.97941 -.513138 274.9538 15.95431 2.13451 1.07470E-03 1.03962E-03 28 0 0 15.91772 -.475085 269.2831 15.83721 2.10463 1.08563E-03 1.06177E-03 28 10 0 15.85623 -.43671 263.6154 15.73969 2.07696 1.09723E-03 1.08299E-03 28 20 0 15.79493 -.398012 257.9505 15.64515 2.05127 1.10963E-03 1.10289E-03 28 30 0 15.73382 -.358987 252.2887 15.56072 2.02864 1.12296E-03 1.12110E-03 28 40 0 15.67291 -.319634 246.6298 15.48881 2.00931 1.13733E-03 1.13732E-03 28 50 0 15.6122 -.279949 240.974 15.42961 1.9925 1.15279E-03 1.15137E-03 29 0 0 15.55169 -.239931 235.3212 15.37668 1.97859 1.16935E-03 1.16313E-03 29 10 0 15.49137 -.199575 229.6715 15.33335 1.9675 1.18695E-03 1.17263E-03 29 20 0 15.43125 -.158878 224.0249 15.30065 1.95891 1.20549E-03 1.18002E-03 29 30 0 15.37131 -.117834 218.3814 15.27699 1.95267 1.22483E-03 1.18554E-03 29 40 0 15.31155 -7.64367E-02 212.7412 15.25799 1.94744 1.24478E-03 1.18956E-03 29 50 0 15.25194 -3.46790E-02 207.1041 15.24814 1.94442 1.26510E-03 1.19251E-03 30 0 0 15.19242 7.44620E-03 201.4703 15.24077 1.94196 1.28556E-03 1.19488E-03 30 10 0 15.13288 4.99299E-02 195.8399 15.23195 1.93928 1.30592E-03 1.19724E-03 30 20 0 15.07298 9.26077E-02 190.2125 15.2215 1.93615 1.32604E-03 1.20015E-03 30 30 0 15.01176 .1336165 184.5855 15.20309 1.93145 1.34590E-03 1.20437E-03 30 40 0 14.95004 .168822 178.9523 15.17797 1.92512 1.36506E-03 1.21024E-03 30 50 0 14.88928 .2016574 173.318 15.14564 1.91693 1.38296E-03 1.21770E-03 31 0 0 14.82914 .234096 167.686 15.10588 1.90673 1.39958E-03 1.22707E-03 31 10 0 14.76942 .2665346 162.0569 15.05794 1.89433 1.41490E-03 1.23859E-03 31 20 0 14.71006 .2990939 156.4309 15.00273 1.87961 1.42893E-03 1.25235E-03 31 30 0 14.65099 .3318238 150.8082 14.93895 1.86268 1.44170E-03 1.26836E-03 31 40 0 14.59222 .3647492 145.1888 14.86883 1.84398 1.45332E-03 1.28653E-03 31 50 0 14.53372 .3978841 139.5727 14.79398 1.82397 1.46390E-03 1.30667E-03 32 0 0 14.47549 .4312369 133.9601 14.71223 1.80225 1.47362E-03 1.32855E-03 32 10 0 14.41753 .4648129 128.3509 14.62675 1.77955 1.48269E-03 1.35185E-03 32 20 0 14.35984 .4986156 122.7452 14.53845 1.75619 1.49133E-03 1.37622E-03 32 30 0 14.30242 .5326472 117.1431 14.4438 1.73121 1.49979E-03 1.40129E-03 32 40 0 14.24527 .566909 111.5444 14.36878 1.71152 1.50829E-03 1.42667E-03 32 50 0 14.1884 .6014018 105.9494 14.28396 1.68928 1.51709E-03 1.45199E-03 33 0 0 14.1318 .6361259 100.3579 14.20335 1.66809 1.52642E-03 1.47689E-03 33 10 0 14.07549 .6710809 94.7701 14.12568 1.64769 1.53649E-03 1.50106E-03 33 20 0 14.01947 .7062665 89.18593 14.05444 1.62887 1.54748E-03 1.52421E-03 33 30 0 13.96375 .7416819 83.60544 13.98783 1.61136 1.55956E-03 1.54614E-03 33 40 0 13.90832 .7773261 78.02866 13.9259 1.59507 1.57284E-03 1.56669E-03 33 50 0 13.85319 .8131977 72.45562 13.86975 1.58035 1.58742E-03 1.58577E-03 34 0 0 13.79838 .8492951 66.88634 13.81902 1.56692 1.60336E-03 1.60335E-03 34 10 0 13.74388 .8856168 61.32085 13.77196 1.55478 1.62068E-03 1.61948E-03 34 20 0 13.6897 .9221607 55.75917 13.73056 1.54384 1.63935E-03 1.63426E-03 34 30 0 13.63584 .9589245 50.20132 13.69224 1.53391 1.65936E-03 1.64783E-03 34 40 0 13.58232 .9959059 44.64733 13.65784 1.52478 1.68061E-03 1.66039E-03 34 50 0 13.52914 1.0331 39.09721 13.62471 1.51617 1.70303E-03 1.67218E-03 35 0 0 13.47631 1.07051 33.55101 13.59493 1.50827 1.72650E-03 1.68347E-03 35 10 0 13.42383 1.10813 28.00872 13.56523 1.50052 1.75089E-03 1.69456E-03 35 20 0 13.3717 1.14595 22.47037 13.53518 1.49259 1.77607E-03 1.70574E-03 35 30 0 13.31994 1.18398 16.93599 13.5045 1.48466 1.80188E-03 1.71734E-03 35 40 0 13.26855 1.2222 11.40559 13.4729 1.47634 1.82818E-03 1.72968E-03 35 50 0 13.21754 1.26062 5.8792 13.43957 1.46737 1.85482E-03 1.74307E-03 36 0 0 13.16692 1.29923 .3568141 13.40071 1.45745 1.88165E-03 1.75781E-03 36 10 0 13.11669 1.33802 354.8384 13.35825 1.44654 1.90854E-03 1.77419E-03 36 20 0 13.06686 1.377 349.3241 13.31194 1.43441 1.93534E-03 1.79247E-03 36 30 0 13.01743 1.41615 343.8139 13.25963 1.42056 1.96193E-03 1.81286E-03 36 40 0 12.96842 1.45547 338.3077 13.21138 1.40799 1.98823E-03 1.83556E-03 36 50 0 12.91984 1.49496 332.8056 13.15193 1.39248 2.01413E-03 1.86072E-03 37 0 0 12.87168 1.53461 327.3077 13.08637 1.37551 2.03958E-03 1.88841E-03