CORE-3040 (Continuous Observations of the Rotation of the Earth-3040) 2001 December 19 Notes prepared by Nancy Vandenberg and Cynthia Thomas,NVI/GSFC Schedule name: dec01/c3040.skd on CDDISA Nominal Start: 18:30 U.T. on December 19 (day 353) first observation at 18:30 U.T. on 2234+282 Nominal Stop: 18:30 U.T. on December 20 (day 354) last observation at 18:19 U.T. on 0048-097 for HH last observation at 18:22 U.T. on 1606+106 for GC-WF last observation at 18:22 U.T. on 0528+134 for NY-WZ Observing Mode: 2F (with barrel roll, see details below) Correlator: Haystack 1 letter 2 letter Station Code Code # of tapes # of obs Occupation Code Fairbanks A Gc 2 (TT) 411 40476601 HartRAO J HH 1 (TT) 149 72326201 Ny Alesund N NY 2 (TT) 439 73313301 Westford E Wf 2 (TT) 396 72097301 Wettzell V Wz 2 (TT) 449 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 station with VLBA backends, Fairbanks, 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 96 seconds Median SNR 35.0 at X-band 20.0 at S-band Number of observations 2173 observations Average scans per station 368 scans Station Information =================== Tigo-Concepcion was scheduled to participate in this session. Unfortunately, Tigo-Conception will not be ready to observe until the second quarter of 2002. Parity ====== This schedule was made with a minimum scan time of less than the 55 seconds required for parity checks. As a result, some parity checks in the schedule may give bad results even though there is nothing wrong. The next release of the FS, 9.5, will correct this problem. In the meantime, please check when a parity check fails to see if the cause is a short scan. If the problem is presistent and occurs frequently at your station for a given schedule type, you may want to disable parity checks for specific experiments of that type. You can do this by creating empty "checkf80" and "checkr80" procedures (or "checkf135" and "checkr135" if you are using thick tape) in the EXPERIMENT procedure library for the effected experiment. If you do this, it is strongly recommend that you verify recorder performance before the experiment by recording some tape in both directions using the experiment set-up and check it with the appropriate parity check procedures. 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 Date Session ==== ========= ==== ======= 01JUL09 CORE-1014 01AUG22 CORE-3026 01JUL11 CORE-3020 01AUG27 CORE-C103 01JUL16 CORE-B902 01AUG29 CORE-3027 01JUL18 CORE-3021 01SEP05 CORE-3028 01JUL23 IRIS-S164 01SEP10 CORE-1016 01JUL25 CORE-3022 01SEP12 CORE-3029 01AUG01 CORE-3023 01SEP19 CORE-3030 01AUG06 IRIS-S165 01SEP24 IRIS-S166 01AUG08 CORE-3024 01SEP26 CORE-3031 01AUG13 CORE-B903 01OCT01 IRIS-S167 01AUG15 CORE-C025 01OCT03 CORE-3032 01AUG20 CORE-1015 01OCT17 CORE-3033 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 $01DEC19ZZ -------------------------------------------------------------------| | | | Maximum | Correlating | | EOP | Formal | Correlation | Parameter | | Parameters | Errors | | | |------------+----------------+-------------+----------------------| | | | | | | X-Wobble | 81.0 muas | -0.05 | WETTZELL Z COMPONENT | | Y-Wobble | 64.4 muas | 0.07 | WETTZELL Z COMPONENT | | UT1-TAI | 2.8 musec | 0.10 | WETTZELL X COMPONENT | | UT1-Rate | 7.7 musec/d | 0.02 | NYALES20 Z COMPONENT | |------------|----------------|-------------|----------------------| Procedures ========== Please generate the procedures for this session using drudg. SKED Summary from file ./c3040.skd for experiment C3040 (all scans with at least one subnet station) SOURCE |0 6 12 18 | #SCANS #OBS #Obs/bl 0003-066I x xx x x x x x I 8 8 2.6 0048-097I x x x xx x x I 7 11 2.9 0059+581I x x x x x x x x x x x x x x x x x x x xI 20 120 17.1 0106+013I x x x x x x x x x x xI 11 20 4.6 0119+115Ix x x x x x x x x x x x x xI 14 37 6.3 0119+041I x I 1 1 .2 0229+131I x x x x x I 5 12 1.9 0235+164I x x x x x x x x x x x x x x x x x x x xI 20 75 12.6 CTA26 I x x x x x x x x x x x x I 12 21 5.2 0454-234Ix x x x x x x x I 8 10 5.4 0458-020I x x x x x x x xx I 9 13 2.7 0528+134I x x x x xx x x x xx x x x x xxx x x x x xI 23 52 7.9 0552+398Ix x x x x x x x x x x x x x x x x x x x x x x I 23 127 17.9 0556+238I x x x x I 4 4 .6 0718+793I x x x x x x x x I 8 48 6.9 0727-115I x x x x x x xI 7 11 2.9 0749+540I x x x x x x x x x x x x x x x xx x x xx xI 22 132 18.9 0804+499I x I 1 6 .9 0805+410Ix x x x x x x x x x x x x x x x x x x x I 20 87 9.1 0823+033Ix x x x x x x x xx x x x x x x I 16 24 5.5 OJ287 Ix x x x x x x x x xx x x x xx x x xx x x x x I 24 94 15.2 0919-260I I 0 0 .0 4C39.25 Ix x x x x x x x x xx x xx x x xx x x x I 21 109 15.2 OK290 I x x x x x x x x x x x x x x x xI 16 28 3.4 0955+476I x x x x x x x x xx xx x x x x x xI 18 99 14.7 1034-293I x x x x I 4 4 2.0 1044+719I x x x x x x x x x x x x x x x x x x xI 19 114 16.3 1053+815I x x x x x x I 6 36 5.1 1124-186I x x x x x I 5 5 2.5 1128+385Ixx x x x x x x x x x x x x x xx x x x x I 21 89 10.3 1219+044I x x x x x x x x x x x xI 12 28 6.2 1255-316I x x x I 3 3 1.5 1300+580Ix x x x x x x x x x x x x x x x x x x x x x I 22 132 18.9 1313-333I I 0 0 .0 1334-127I xx x x x x x x x I 9 9 2.6 1351-018I x x x x x x x x I 8 10 4.4 1357+769Ix x x x x x x x x x x x x x x x x x I 18 108 15.4 1606+106I x x xx x x x x x x x x xx x x I 16 43 8.0 1622-253I x x xx x I 5 5 2.6 NRAO512 Ix x x x x x x x x x x x x x x x x x x x I 20 91 9.8 1726+455I x x x x x x x I 7 39 5.8 1739+522I x x x x x x x x x x x x x I 13 78 11.2 1741-038I x x x x x x x x x x I 10 10 2.4 1749+096I x x x x x x x x x x xx x x x xx x I 18 62 12.2 1908-201I x x xx x x I 6 6 3.5 1921-293I x x x x I 4 4 2.0 1958-179I xx x x x x I 6 10 5.5 2121+053I x x x x x x x x x x xx x xI 14 32 7.0 2128-123I x x x I 3 3 .9 2134+00 I I 0 0 .0 2145+067I x x x x x x x x xI 9 25 5.3 2234+282Ix x xx x x x x x x x x x x x x x xx xI 20 77 10.3 2255-282I x I 1 1 .5 Total scans, obs: 597 2173 Average number of obs. per baseline per source (normalized by up-time) = 7.0 Min = .0 Max = 25.2 (Baseline Gc-Ny on OJ287 ) RMS = 7.4 Total time: 1433 minutes ( 23.9 hours). Key: Gc=GILCREEK Hh=HARTRAO Ny=NYALES20 Wf=WESTFORD Wz=WETTZELL Gc Hh Ny Wf Wz Avg % obs. time: 37 23 42 44 47 39 % cal. time: 4 1 5 4 5 4 % slew time: 25 29 23 17 17 22 % idle time: 32 46 28 33 29 33 # of tapes : 1.1 .6 1.2 1.2 1.3 total # scans: 411 149 439 396 449 368 # scans/hour : 17 6 18 16 18 15.4 Avg scan (sec): 78 132 83 96 91 96 # OF OBSERVATIONS BY BASELINE | Gc Hh Ny Wf Wz StnTotal ---------------------------------- Gc|411 18 346 338 267 969 Hh| 149 72 43 145 278 Ny| 439 305 356 1079 Wf| 396 283 969 Wz| 449 1051 Number of 2-station scans: 209 Number of 3-station scans: 140 Number of 4-station scans: 234 Number of 5-station scans: 14 Total # of scans, observations: 597 2173 Average baseline components for all observations Average XY = 4640. Average XZ = 4209. Average YZ = 3902. Average length = 5452.