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 10-1-96 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 Dec 7, 1995 00:00:00 Position is Jovian geographic coordinates calculated from the JPL SPICE kernel with input files: gll00007.tpc, gll00007.tls, and s960729a.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 Questions contact Chris Paranicas, APL 301-953-5000 x8652 14 0 0 8.7724 -2.39956 197.5089 8.70099 4.21773 6.72495E-03 6.44232E-03 14 10 0 8.64196 -2.33507 192.2366 8.58798 4.1249 7.05285E-03 6.68946E-03 14 20 0 8.51147 -2.26814 186.9879 8.47889 4.03218 7.39735E-03 6.95122E-03 14 30 0 8.38098 -2.19866 181.764 8.3682 3.93792 7.75833E-03 7.23102E-03 14 40 0 8.25049 -2.12651 176.566 8.25451 3.84114 8.13581E-03 7.53238E-03 14 50 0 8.12005 -2.05154 171.3951 8.13373 3.73849 8.52998E-03 7.85876E-03 15 0 0 7.98967 -1.97363 166.2527 8.02368 3.64497 8.94131E-03 8.21347E-03 15 10 0 7.85941 -1.89261 161.1401 7.90196 3.54198 9.37058E-03 8.59961E-03 15 20 0 7.72929 -1.80834 156.0589 7.77742 3.43656 9.81894E-03 9.02004E-03 15 30 0 7.59935 -1.72064 151.0105 7.65123 3.32997 1.02880E-02 9.47726E-03 15 40 0 7.46965 -1.62934 145.9968 7.52321 3.22143 1.07796E-02 9.97349E-03 15 50 0 7.34023 -1.53425 141.0193 7.39358 3.11199 1.12964E-02 1.05107E-02 16 0 0 7.21116 -1.4352 136.08 7.26249 3.00209 1.18411E-02 1.10906E-02 16 10 0 7.08248 -1.33197 131.1809 7.13143 2.89209 1.24171E-02 1.17148E-02 16 20 0 6.95428 -1.22437 126.324 7.00087 2.78269 1.30281E-02 1.23846E-02 16 30 0 6.82661 -1.11216 121.5116 6.87089 2.67396 1.36781E-02 1.31017E-02 16 40 0 6.69957 -.995146 116.7459 6.74257 2.56676 1.43715E-02 1.38676E-02 16 50 0 6.57324 -.873083 112.0295 6.61543 2.46081 1.51130E-02 1.46843E-02 17 0 0 6.4477 -.745741 107.3649 6.48969 2.35631 1.59075E-02 1.55537E-02 17 10 0 6.32307 -.612881 102.7549 6.36698 2.25385 1.67601E-02 1.64785E-02 17 20 0 6.19945 -.474256 98.2023 6.24448 2.15319 1.76762E-02 1.74616E-02 17 30 0 6.07694 -.329595 93.71009 6.12482 2.05425 1.86610E-02 1.85066E-02 17 40 0 5.95556 -.178484 89.28134 6.0066 1.95699 1.97212E-02 1.96182E-02 17 50 0 5.83487 -1.86196E-02 84.91152 5.88981 1.86118 2.08683E-02 2.08068E-02 18 0 0 5.71595 .1495118 80.59773 5.77531 1.76748 2.20984E-02 2.20680E-02 18 10 0 5.5989 .3243809 76.35569 5.66319 1.67565 2.34170E-02 2.34068E-02 18 20 0 5.48376 .5062265 72.18981 5.55227 1.5859 2.48298E-02 2.48291E-02 18 30 0 5.37071 .6951715 68.10377 5.44371 1.49797 2.63410E-02 2.63392E-02 18 40 0 5.25995 .8912596 64.10119 5.33737 1.41218 2.79533E-02 2.79410E-02 18 50 0 5.15173 1.09445 60.18564 5.23331 1.3285 2.96685E-02 2.96371E-02 19 0 0 5.04629 1.30462 56.36055 5.13166 1.24709 3.14864E-02 3.14289E-02 19 10 0 4.94392 1.52153 52.62917 5.0327 1.16817 3.34049E-02 3.33154E-02 19 20 0 4.84491 1.7448 48.99446 4.93693 1.09208 3.54192E-02 3.52939E-02 19 30 0 4.74958 1.97391 45.45901 4.84434 1.01879 3.75216E-02 3.73583E-02 19 40 0 4.65827 2.20817 42.02486 4.75506 .9485843 3.97004E-02 3.94990E-02 19 50 0 4.57132 2.44669 38.69343 4.66998 .8818705 4.19403E-02 4.17021E-02 20 0 0 4.48912 2.6884 35.46529 4.58925 .8188313 4.42209E-02 4.39486E-02 20 10 0 4.41202 2.93196 32.34007 4.51317 .7596998 4.65172E-02 4.62150E-02 20 20 0 4.34042 3.17586 29.31625 4.44203 .7048022 4.87991E-02 4.84718E-02 20 30 0 4.2747 3.41833 26.39101 4.37631 .6542006 5.10314E-02 5.06844E-02 20 40 0 4.21524 3.65741 23.56009 4.3173 .6089415 5.31751E-02 5.28137E-02 20 50 0 4.16241 3.89096 20.81767 4.26434 .5684388 5.51875E-02 5.48169E-02 21 0 0 4.11655 4.11673 18.15633 4.21785 .5331786 5.70244E-02 5.66482E-02 21 10 0 4.07798 4.33239 15.56702 4.1788 .5035759 5.86413E-02 5.82628E-02 21 20 0 4.04697 4.53561 13.0391 4.14717 .4796248 5.99965E-02 5.96177E-02 21 30 0 4.02377 4.72418 10.56052 4.12315 .4614934 6.10526E-02 6.06737E-02 21 40 0 4.00855 4.89603 8.11804 4.10696 .4493262 6.17795E-02 6.13994E-02 21 50 0 4.00144 5.04939 5.69743 4.09877 .4431565 6.21562E-02 6.17730E-02 22 0 0 4.00248 5.18279 3.28393 4.10104 .4428904 6.21724E-02 6.17830E-02 22 10 0 4.01166 5.2952 .8625621 4.10665 .4491199 6.18291E-02 6.14294E-02 22 20 0 4.02893 5.38598 358.4185 4.12264 .4611515 6.11388E-02 6.07240E-02 22 30 0 4.05414 5.45496 355.9377 4.146 .4787545 6.01241E-02 5.96894E-02 22 40 0 4.08709 5.50239 353.4067 4.17774 .5028437 5.88164E-02 5.83572E-02 22 50 0 4.12754 5.52893 350.8137 4.21655 .5321397 5.72537E-02 5.67651E-02 23 0 0 4.17521 5.53556 348.148 4.26242 .5670545 5.54780E-02 5.49557E-02 23 10 0 4.22976 5.52357 345.4004 4.3151 .6073147 5.35330E-02 5.29739E-02 23 20 0 4.29084 5.49442 342.5637 4.3742 .6525729 5.14619E-02 5.08649E-02 23 30 0 4.35809 5.44974 339.6321 4.43901 .7024703 4.93056E-02 4.86702E-02 23 40 0 4.43111 5.39121 336.6014 4.5093 .7568327 4.71012E-02 4.64299E-02 23 50 0 4.50954 5.32054 333.4687 4.5848 .8154304 4.48813E-02 4.41781E-02 24 0 0 4.59297 5.23939 330.2326 4.66462 .8777393 4.26738E-02 4.19451E-02 24 10 0 4.68105 5.14936 326.8928 4.74896 .9437909 4.05014E-02 3.97558E-02 24 20 0 4.7734 5.05194 323.4499 4.83664 1.01284 3.83818E-02 3.76300E-02 24 30 0 4.86966 4.94855 319.9051 4.92768 1.08472 3.63292E-02 3.55833E-02 24 40 0 4.96921 4.841 316.2531 5.02111 1.15894 3.43593E-02 3.36326E-02 24 50 0 5.07152 4.73069 312.4942 5.11607 1.23464 3.24815E-02 3.17882E-02 25 0 0 5.17617 4.61866 308.6323 5.21139 1.31097 3.07000E-02 3.00537E-02 25 10 0 5.28277 4.50579 304.6715 5.3092 1.38936 2.90162E-02 2.84297E-02 25 20 0 5.39098 4.39277 300.6169 5.40699 1.46833 2.74294E-02 2.69135E-02 25 30 0 5.50098 4.27946 296.4804 5.50536 1.54794 2.59305E-02 2.54931E-02 25 40 0 5.61271 4.16617 292.268 5.60439 1.62827 2.45154E-02 2.41610E-02 25 50 0 5.72598 4.05333 287.983 5.70417 1.70953 2.31817E-02 2.29108E-02 26 0 0 5.84063 3.9413 283.6289 5.80502 1.79163 2.19269E-02 2.17356E-02 26 10 0 5.95651 3.83037 279.2089 5.90631 1.87482 2.07481E-02 2.06278E-02 26 20 0 6.07348 3.72079 274.7261 6.00935 1.95935 1.96426E-02 1.95802E-02 26 30 0 6.19141 3.61276 270.1837 6.11417 2.04554 1.86075E-02 1.85858E-02 26 40 0 6.31018 3.50645 265.5845 6.22119 2.13391 1.76398E-02 1.76382E-02 26 50 0 6.4297 3.40196 260.9315 6.33115 2.22481 1.67363E-02 1.67316E-02 27 0 0 6.54987 3.2994 256.2272 6.44428 2.31854 1.58936E-02 1.58613E-02 27 10 0 6.67058 3.19884 251.4742 6.56196 2.41588 1.51083E-02 1.50239E-02 27 20 0 6.79178 3.10032 246.6749 6.68366 2.51682 1.43766E-02 1.42169E-02 27 30 0 6.91337 3.00387 241.8316 6.8091 2.62224 1.36947E-02 1.34390E-02 27 40 0 7.03531 2.9095 236.9466 6.94007 2.7318 1.30584E-02 1.26902E-02 27 50 0 7.15751 2.81722 232.0217 7.07568 2.8455 1.24636E-02 1.19709E-02 28 0 0 7.27994 2.72702 227.059 7.21667 2.96373 1.19063E-02 1.12826E-02 28 10 0 7.40253 2.63888 222.0604 7.36214 3.08605 1.13823E-02 1.06269E-02 28 20 0 7.52525 2.55278 217.0275 7.511 3.21166 1.08879E-02 1.00057E-02 28 30 0 7.64805 2.46868 211.9619 7.66349 3.34015 1.04196E-02 9.42055E-03 28 40 0 7.77089 2.38655 206.8653 7.81791 3.47079 9.97411E-03 8.87291E-03 28 50 0 7.89374 2.30635 201.739 7.97242 3.60101 9.54868E-03 8.36362E-03 29 0 0 8.01656 2.22805 196.5844 8.12942 3.73374 9.14099E-03 7.89295E-03