JPNTI1 (JAPAN TIES 1) 1998 October 20 Notes prepared by Nancy Vandenberg & Cynthia Thomas, NVI/GSFC Schedule name: JPNTI1.SKD on CDDISA Nominal Start: 05:00 U.T. on October 20 (day 293) first observation at 05:00 U.T. on 0059+581 Duration: 24 hours Nominal Stop: 05:00 U.T. on October 21 (day 294) last observation at 05:01 U.T. on 1606+106 Correlator: Washington **Frequency Sequence**: CDPSX - Standard CDP SX sequence. (360 MHz wide at X, 85 MHz wide at S) 1 letter 2 letter Station Code Code # of tapes # of obs Occupation Code Kashima-26m Q KA 3 (HDT) 313 18567601 Kashima-34m O KB 3 (HDT) 313 18575801 Tsukuba T Ts 1 (TT) 313 73452301 Purpose ======= The purpose of this experiment is to make a precise VLBI measurement of the short baseline between the three Japanese antennas. This is the first experiment designed to obtain an accurate geodetic tie between Kashima-26m, Kashima-34m, and Tsukuba. This tie will enable the long history of observations with Kashima-26m and Kashima-34 to be transferred to Tsukuba. Schedule ======== This is a new schedule generated by C. Thomas with the automatic mode of sked. The following are the characteristics of the schedule: 1) This schedule was optimized for sky coverage. 2) Only the observations in the previous one hour of the schedule were considered for the minor options. The best 20% of the configurations were considered for minor options. 3) The "minor options" were set to select observations to maximize the total number of observations, to minimize the idle time between scans, and to minimize time between scans on the same source by thirty minutes. 5) The minimum SNR limits for all baselines were set to 20 for X-band and 15 for S-band. 6) This schedule was made using 68 sources which helped improve the sky coverage. Flux Information ================ Several years ago John Gipson wrote a program called snranal which compares the measured performance of an experiment with respect to the predicted. One of the things this program calculates is an empirical flux density for each source. Recently J. Gipson compared the fluxes generated by this program with those from more careful modeling. The agreement is generally good (~15%) for those sources which have been observed more than 20 times. In order to account for changes in the flux catalog since the last update, J. Gipson adjusted the fluxes in the flux catalog for the sources in the current source catalog using the 98Mar03 NEOS-A253 and the 98JAN27XA CORE-A028 experiments. Antennas and Equipment ====================== Kashima 34m antenna will use the K3 rack and VLBA recorder, controlled by FS9 [to be confirmed]. Antenna control will be done with a separate PC. Log files from this PC are compatible with FS logs. Summary files for the correlator could be produced if necessary. Kashima 26m antenna will be run in the same configuration as for the CORE-B sessions, controlled by FS9 [to be confirmed]. Tsukuba 32m antenna will be run in the same configuration as for the CORE sessions, controlled by FS9. All three antennas will also record the data with K4 recorders. The K4 data will be processed at GSI and/or at CRL. Special Procedures ================== The hydrogen maser at Kashima 34m antenna is used for the 11m Keystone antenna and since this maser is in use for the Keystone Project it cannot be shifted. The hydrogen maser at Kashima 26m antenna is the same type as the one with the 34m. CRL will determine how to shift the maser frequency and inform GSI. The maser output is at 10 MHz, so the shift will be 0.1 Hz. The offset will be made in the electronics output of the maser and does not affect the physics package. At 8 Ghz an offset of 1x10^8 will result in an 80 Hz difference between the observing frequencies and thus about an 80 Hz fringe rate. The frequency offset will cause a differential clock rate in the offset maser of 10 ns/s or 864 microseconds in 24 hours. Because the epoch of the offset maser will drift rapidly, the time dfiference between the maser and GPS clock will be monitored and logged periodically. The correlator will use this information to find fringes and to set up the processing. GSI will monitor the clock offset at least once per hour and provide the values in an e-mail message or a separate file for the correlator. Correlation ========== This experiment will be correlated at the Washington Correlator with all baselines being correlated. SKED Summary from file ./jpnti1.skd for experiment JPNTI1 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I x x x x x I 5 15 11.6 0048-097I x x I 2 6 4.8 0059+581I x x x x x x x x x x x x x I 13 39 14.7 0104-408I x x x I 3 9 14.4 0106+013I x x I 2 6 4.3 0119+115I x x x x I 4 12 7.9 0119+041I x x x I 3 9 6.3 0229+131I x x x I 3 9 5.9 0235+164I x x x x I 4 12 7.6 3C84 I xx x x x x x x x x x x I 12 36 18.3 CTA26 I x x x x x I 5 15 11.1 NRAO150 I x I 1 3 1.3 0402-362I xx x I 3 9 11.6 0454-234I x x x x x x x x I 8 24 22.9 0458-020I x x x x x I 5 15 11.1 0528+134Ix x x x x xx x x I 9 27 17.5 0537-441I x I 1 3 6.5 0552+398I x I 1 3 1.5 0556+238I x x x I 3 9 5.4 0718+793I x x x x x x I 6 18 6.0 0727-115Ix x I 2 6 4.9 0749+540Ix x x x x x x x x x I 10 30 12.8 0804+499I x x I 2 6 2.7 0805+410I x x x x x x x x x x I 10 30 15.3 0823+033I xx x x x x x xI 8 24 16.9 OJ287 I x x x x x x x x x xI 10 30 18.4 0919-260Ix x x x x x x I 7 21 20.9 0920-397I x x xI 3 9 13.7 4C39.25 I x x I 2 6 3.1 OK290 I x x I 2 6 3.5 0955+476I x xx I 3 9 4.3 1034-293I x x I 2 6 6.4 1044+719I x x I 2 6 2.0 1053+815Ix x I 2 6 2.0 1104-445I I 0 0 .0 1124-186I x x I 2 6 5.3 1128+385I x x x x x x x x I 8 24 12.6 1144-379I I 0 0 .0 1219+044Ix x x x x x x x I 8 24 16.7 3C273B I x x x I 3 9 6.4 1255-316I x x x I 4 12 13.5 1300+580I x x x x x x x x x x x I 11 33 12.7 1308+326I x x x I 3 9 5.0 1313-333I x xI 2 6 7.1 1334-127I I 0 0 .0 1351-018I I 0 0 .0 1357+769I x x x x x x I 6 18 6.0 1424-418I x x I 2 6 10.6 1451-375I x I 1 3 4.2 1606+106I x x x x xx x x x x xI 11 33 21.9 1622-253I x x x x x x I 7 21 20.7 NRAO512 I x x x x x x x x x x xI 11 33 17.0 3C345 I I 0 0 .0 1726+455I I 0 0 .0 1739+522I x x x x x x x x x I 9 27 11.8 1741-038I x x x x x x x x x x I 10 30 22.6 1749+096I x x x I 3 9 6.0 1908-201I x x x x I 4 12 10.9 1921-293I x I 1 3 3.2 1954-388I x x x x x I 5 15 21.7 1958-179I x x x I 3 9 7.9 2121+053I x x x x x x x x x x I 10 30 20.8 2128-123I x x x x I 4 12 9.8 2134+00 I x x x I 3 9 6.5 2145+067I x I 1 3 2.1 2234+282I x x xx x x x x x x x I 11 33 19.0 3C454.3 I x x x x x x I 6 18 11.5 2255-282I x x x x x x I 6 18 18.7 Total scans, obs: 313 939 Average number of obs. per baseline per source (normalized by up-time) = 9.6 Min = .0 Max = 23.2 (Baseline Kb-Ka on 0454-234) RMS = 6.7 Total time: 1442 minutes ( 24.0 hours). Key: Kb=KASHIM34 Ka=KASHIMA Ts=TSUKUB32 Kb Ka Ts Avg % obs. time: 33 33 28 31 % cal. time: 3 3 3 3 % slew time: 52 36 11 33 % idle time: 10 27 55 31 # of tapes : 2.1 2.1 .5 total # scans: 313 313 313 313 # scans/hour : 13 13 13 13.0 Avg scan (sec): 92 92 79 87 # OF OBSERVATIONS BY BASELINE | Kb Ka Ts StnTotal -------------------------- Kb|313 313 313 626 Ka| 313 313 626 Ts| 313 626 Number of 2-station scans: 0 Number of 3-station scans: 313 Total # of scans, observations: 313 939 Average baseline components for all observations Average XY = 35. Average XZ = 28. Average YZ = 24. Average length = 36.