CORE-3013 (Continuous Observations of the Rotation of the Earth-3013) 2001 April 04 Notes prepared by Nancy Vandenberg and Cynthia Thomas,NVI/GSFC Schedule name: apr01/c3013.skd on CDDISA Nominal Start: 18:30 U.T. on April 04 (day 094) first observation at 18:30 U.T. on 1726+455 Nominal Stop: 18:30 U.T. on April 05 (day 095) last observation at 18:10 U.T. on 1741-038 for GC-KK last observation at 18:13 U.T. on OK290 for ON last observation at 18:16 U.T. on 0454-234 for MC-WF-WZ Observing Mode: 2F (with barrel roll, see details below) Correlator: Bonn 1 letter 2 letter Station Code Code # of tapes # of obs Occupation Code Fairbanks A Gc 1 (TT) 337 40476601 Kokee K Kk 2 (TT) 270 72983001 Medicina B Mc 1 (TT) 368 72308801 Onsala T On 2 (TT) 314 72137701 Westford E Wf 2 (TT) 305 72097301 Wettzell V Wz 2 (TT) 354 72247801 Purpose ======= The CORE-3 sessions marked the start of the regular CORE oberving program. These sessions will provide a bi-weekly 48-hour continuous data set from January through July (NEOS + CORE-3) and a weekly 48-hour continuous data set from July through December. The CORE-3 sessions will be recorded in a Mark 4 mode which requires that the participating stations have Mark 4 capability. Observing Mode ============== This is the first CORE series that uses a "Mark 4" style observing mode. The mode for CORE-3 uses fan-out and records on all 32 tracks to achieve a data rate of 128 Mb/s, more than twice that of the standard geodetic Mode C which is 56 Mb/s. CORE Mode "2F" (twice the standard mode C, fanned out) ----------------------------------------------------------------- Number of frequencies 14 (standard wide-band frequency sequence modified to avoid RFI at Matera) Number of channels 16 (14 USB + 2 LSB) Channel bandwidth 4.0 MHz Sample rate 8 Mb/s Bits per sample 1 Total data rate 128 Mb/s Data rate on tape 4 Mb/s/track Fan-out 1:2 Tape speed 80 ips Tracks per pass 32 Passes per tape 14 Barrel roll yes (*) Track frame format Mark4 and VLBA (*) The 16 recorded channels are comprised of the standard 14-channel USB frequency sequence plus the LSB channels of the first and last frequencies at X-band. The two outer X-band LSB channels give extra sensitivity. They also slightly narrow the peak of the delay resolution function, resulting in better group delay precision. *The stations with VLBA backends, Fairbanks and Kokee, will use barrel roll during this session and record in VLBA (non-data replacement) format. Stations with Mark 4 formatters cannot barrel roll. Schedule ======== This schedule was made by C. Thomas using sked. Schedule setup parameters: Early start 10 sec (*) Minimum scan length 30 sec Maximum scan length 600 sec Minimum SNR 20 at X-band, margin of 5 15 at S-band, margin of 3 Automatic scheduling setup: optimize for uniform sky coverage at all stations, maximize the number of observations, minimize slewing time, minimize time between scans, consider the top 50% of ranked scans for selection, consider the last 1 hour of scans for sky coverage calculations, minimum 50 min between scans on the same source. The characteristics of the generated schedule are listed below. These will vary slightly for each schedule that is generated. The characteristics also will change when Matera and Ny Alesund are used in the network instead of Medicina and Onsala. Schedule characteristics: Average scan length 104 seconds Average SNR 62.9 at X-band 34.3 at S-band Number of observations 2941 observations Average scans per station 324 scans Flux Information ================ Program snranal compares the measured performance of a session with respect to the predicted. The program calculates an empirical flux density for each source. In order to account for changes in the flux catalog since the last update based on source modeling, the fluxes in the flux catalog for the sources in the current source catalog were adjused using the following databases: Date Session ==== ========= 00OCT03 NEOS-A388 00OCT24 NEOS-A391 00OCT31 NEOS-A392 00NOV14 NEOS-A394 00NOV28 NEOS-A396 00DEC12 NEOS-A398 01JAN08 NEOS-A398 01JAN16 NEOS-A398 01JAN23 NEOS-A398 01JAN30 NEOS-A398 01FEB06 NEOS-A398 01FEB13 NEOS-A398 Simulation Results ================== Simulated data from this schedule was used in a global solution to estimate the formal errors. The table below lists the formal errors for Earth orientation parameters. These results meet the simulation goals for the CORE-3 network. Also shown in the table are the maximum correlations between the Earth orientation parameters and other parameters. Simulation for experiment $01APR04ZZ -------------------------------------------------------------------| | | | Maximum | Correlating | | EOP | Formal | Correlation | Parameter | | Parameters | Errors | | | |------------+----------------+-------------+----------------------| | | | | | | X-Wobble | 43.5 mas | -0.07 | WETTZELL Z COMPONENT | | Y-Wobble | 35.8 mas | 0.34 | MEDICINA Y COMPONENT | | UT1-TAI | 1.7 musec | 0.20 | MEDICINA Z COMPONENT | | UT1-Rate | 2.6 musec/d | 0.09 | MEDICINA X COMPONENT | |------------|----------------|-------------|----------------------| Procedures ========== Please generate the procedures for this session using drudg. SKED Summary from file ./c3013.skd for experiment C3013 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I x x x x x x x x x x x x x x xx xI 17 51 8.6 0048-097I x x x xI 4 11 1.9 0059+581I x x x x x x x x x I 9 116 8.6 0106+013I I 0 0 .0 0119+115I I 0 0 .0 0119+041I I 0 0 .0 0229+131I x x x x xx x x x x x x xI 13 41 4.9 0235+164I x x x x x x x x x x x I 11 62 7.2 CTA26 Ix x x x xx x x x x x x x x x xx x x I 19 57 8.8 0454-234Ix x x x x x xx x x I 10 21 7.5 0458-020I x x x x x x x x x x x x x x x x xI 17 50 7.7 0528+134Ix x x x xx x x x x x x x x x x x x x x I 20 66 7.9 0552+398Ix x x x x x x x x x x x x x x x x x x x x I 21 202 16.9 0556+238I x x x x I 4 6 .6 0718+793I x x x x x x x x x x x x x I 13 15 1.0 0727-115I x x x x x x x x x x x xx x x I 15 38 8.0 0749+540I x x x x x x x x x x I 10 130 9.6 0804+499I x x x x x x x x xI 9 110 8.5 0805+410I x x x x x I 5 44 3.6 0823+033I x x x x x x x x x x x x x x x x x x xI 19 64 8.9 OJ287 I x xx x x xx x x x x x x x x x x x xI 19 82 8.9 0919-260I x x x x x I 5 9 4.5 4C39.25 Ix xx x x x x x x x x x x x x x x I 17 150 12.6 OK290 I x x x x x x x x x x I 10 16 1.6 0955+476I x x x x x x x x I 8 95 7.6 1044+719I x x x x x x x x x x x x I 12 134 9.2 1053+815I I 0 0 .0 1124-186I x x x x x x x x xx xI 11 29 9.0 1128+385I x x x x x x x x x x x x x x x x x xI 18 168 14.4 1219+044I x x x x x x x x x x I 10 22 3.0 1255-316I x x x xI 4 4 2.2 1300+580Ix x x x x x x x x x I 10 88 6.6 1313-333I I 0 0 .0 1334-127I x x x x x x x x x x x xx x xI 15 40 8.5 1351-018I x x x x x x x x I 8 14 2.2 1357+769Ix x x x x x x x x x x x x x x x x x x I 19 285 19.0 1606+106Ix x x x x x x x x x x x x x x x x x x xx x I 22 82 10.3 1622-253I x x x x x x x xI 8 16 6.6 NRAO512 I x x x x x I 5 42 3.5 1726+455I x x x x x x I 6 70 5.7 1739+522Ix x x x x x x x x x x I 11 125 9.0 1741-038I x x x x x x x x x x xx x x x x xI 17 53 8.4 1749+096Ix x x x x x x x x x x x x x x x x x x x xI 21 86 10.9 1908-201I x x x x x xx x x x I 10 25 8.0 1921-293I x x x x x I 5 5 2.4 1958-179I x x x x x x I 6 12 3.4 2121+053Ix x x x x x x x x x xx I 12 26 3.5 2128-123I x x x x x x x x x x x x I 12 26 6.1 2134+00 I x x x x I 4 12 1.7 2145+067I x x x x x x x x x xI 10 51 6.7 2234+282Ix x x x x x x x x x x x xx x x x I 17 84 8.1 2255-282I x xx x x x I 6 6 2.8 Total scans, obs: 554 2941 Average number of obs. per baseline per source (normalized by up-time) = 6.4 Min = .0 Max = 30.9 (Baseline Gc-Kk on 2128-123) RMS = 6.7 Total time: 1427 minutes ( 23.8 hours). Key: Gc=GILCREEK Kk=KOKEE Mc=MEDICINA On=ONSALA60 Wf=WESTFORD Wz=WETTZELL Gc Kk Mc On Wf Wz Avg % obs. time: 34 39 26 46 48 37 39 % cal. time: 3 3 4 3 3 4 3 % slew time: 23 14 38 20 14 10 20 % idle time: 37 42 30 29 32 47 36 # of tapes : 1.0 1.1 .8 1.3 1.3 1.1 total # scans: 337 270 368 314 305 354 324 # scans/hour : 14 11 15 13 12 14 13.5 Avg scan (sec): 88 125 62 126 136 90 104 # OF OBSERVATIONS BY BASELINE | Gc Kk Mc On Wf Wz StnTotal -------------------------------------- Gc|337 244 177 163 214 166 964 Kk| 270 85 97 175 95 696 Mc| 368 291 203 343 1099 On| 314 188 302 1041 Wf| 305 198 978 Wz| 354 1104 Number of 2-station scans: 150 Number of 3-station scans: 175 Number of 4-station scans: 86 Number of 5-station scans: 79 Number of 6-station scans: 64 Total # of scans, observations: 554 2941 Average baseline components for all observations Average XY = 4561. Average XZ = 3946. Average YZ = 2768. Average length = 4824.